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All material appearing in this report is in the public domain and may be 

reproduced or copied without permission; citation as to source, however, is appreciated.

Suggested citation

Lloyd PC, Helms VE, Simon AE, et al. Linkage of 1999–2012 National Health 

Interview Survey and National Health and Nutrition Examination Survey data 

to U.S. Department of Housing and Urban Development administrative records. 

National Center for Health Statistics. Vital Health Stat 1(60). 2017.

Library of Congress Cataloging-in-Publication Data

Names: National Center for Health Statistics (U.S.), issuing body.

Title: Linkage of 1999-2012 National Health Interview Survey and National 

   Health and Nutrition Examination Survey data to U.S. Department of Housing and Urban Development administrative records.

Other titles: Vital and health statistics. Ser. 1, Programs and collection 

   procedures ; no. 60. | DHHS publication ; no. 2018-1336. 0276-4733

Description: Hyattsville, Maryland : U.S. Department of Health and Human 

   Services, Centers for Disease Control and Prevention, National Center for Health Statistics, October 2017. | Series: Vital and health statistics. 

   Series 1, Program and collection procedures ; Number 60 | Series: DHHS pub 

   ; number 2018-1336 | "October 2017." | Includes bibliographical references.

Identifiers: LCCN 2017045165| ISBN 9780840606853 (pbk.) | ISBN 0840606850 

   (pbk.)

Subjects:   |MESH: National Health Interview Survey (U.S.) | National Health and Nutrition Examination Survey (U.S.) | United States. Department of 

   Housing and Urban Development. | 

  Health Surveys--methods | Records as 

   Topic | United States Government Agencies | United States

Classification: LCC RA407.3 | NLM W2 A N148va no. 60 2017 | DDC 614.4/ 

   273--dc23 LC record available at https://lccn.loc.gov/2017045165

For sale by the U.S. Government Printing Office 

Superintendent of Documents 

Mail Stop: SSOP 

Washington, DC 20402–9328 

Printed on acid-free paper.

Vital and Health Statistics

Series 1, Number 60

Linkage of 1999–2012 National 

Health Interview Survey and 

National Health and Nutrition 

Examination Survey Data to 

U.S. Department of Housing 

and Urban Development  

Administrative Records

Programs and Collection Procedures

U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES 

Centers for Disease Control and Prevention 

National Center for Health Statistics

Hyattsville, Maryland  

October 2017  

DHHS Publication No. (PHS) 2018–1336

National Center for Health Statistics

Charles J. Rothwell, M.S., M.B.A.,  Director 

Jennifer H. Madans, Ph.D.,  Associate Director for Science

Office of Analysis and Epidemiology

Irma E. Arispe, Ph.D.,  Director

Makram Talih, Ph.D.,  Associate Director for Science

Contents 

Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .v

Abstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1

Data Sources .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .2

NHIS  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .2

NHANES .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .2 

HUD Administrative Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2

Data Linkage Approval, Eligibility, and Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3

Linkage Approval and Eligibility.   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .3 

Linkage Process  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4

Linked NCHS–HUD Data .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .5

General Description of Linked Data Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5 

Access to Linked NCHS–HUD Data Files .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .7

Analytic Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7

Sample Weights.   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .8 

Analyses Using Linked NCHS–HUD Data  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8

Descriptive Analyses of Linked NHIS–HUD and NHANES–HUD Participants .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .8 

Conclusion   . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

Published Research Papers Using NCHS Surveys Linked to HUD Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Appendix I. U.S. Department of Housing and Urban Development’s Largest Housing Assistance Programs . . . . . . . . . . . . 21

Appendix II. Summary of Linked National Center for Health Statistics–U.S. Department of Housing

and Urban Development Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 

Appendix III. Data Variable Considerations.   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   . 23

Appendix IV. Evaluation of NCHS–HUD Data Linkage: Comparison With HUD Program Recipients . . . . . . . . . . . . . . . 25

iii

Detailed Tables

1. 

Sample size and percentage of survey participants linked to HUD data, by survey year and age at interview:  

National Health Interview Survey, 1999–2012 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

2.  

Sample size and percentage of survey participants linked to HUD data, by survey year and age at interview:  

National Health and Nutrition Examination Survey, 1999–2012 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

3.  

Linked NCHS–HUD file sample size and percentage of linked survey participants with concurrent HUD 

enrollment within 1, 2, and 3 years of survey interview, by survey and age at interview.   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   . 15

4.  

Unweighted sample size and weighted percent distribution of ever-linked 2008–2012 NHIS–HUD participants 

aged 0–17 years, by selected sociodemographic and health characteristics.   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   . 17

5.  

Unweighted sample size and weighted percent distribution of ever-linked 2008–2012 NHIS–HUD participants 

aged 18 and over, by selected sociodemographic and health characteristics . . . . . . . . . . . . . . . . . . . . . . . . . 18

6. 

Unweighted sample size and weighted percent distribution of ever-linked 2009–2012 NHANES–HUD participants 

aged 0–17 years, by selected sociodemographic and health characteristics.   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   . 19

7. 

Unweighted sample size and weighted percent distribution of ever-linked 2009–2012 NHANES–HUD participants 

aged 18 and over, by selected sociodemographic and health characteristics . . . . . . . . . . . . . . . . . . . . . . . . . 20

Text Figures

1.  

Process used to link National Center for Health Statistics survey data to U.S. Department of Housing and  

Urban Development administrative data sources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  4

2. 

Temporal alignment of National Center for Health Statistics surveys linked to U.S. Department of Housing and  

Urban Development administrative data files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6

Appendix Tables

I. 

Linked NCHS–HUD data files: Name, population, and description  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

II. 

Number and percent distribution of concurrently linked 2012 NHIS–HUD participants and 2012 

HUD-assisted tenants, by HUD program and selected HUD-collected demographic characteristics.   .   .   .   .   .   .   .   .   .   .   .   . 26

III.   Number and percent distribution of concurrently linked 2009–2012 NHANES–HUD participants and 

2009–2012 HUD-assisted tenants, by HUD program and selected HUD-collected demographic characteristics . . . . . . 29

Appendix Figures

I.  

All 2012 HUD-assisted tenants and concurrently linked 2012  NHIS–HUD participants, 

by HUD housing category .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   . 27

II.  

All 2012 HUD-assisted tenants and concurrently linked 2012  NHIS–HUD participants, 

by sex and age group.   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   . 27

III.   All 2012 HUD-assisted tenants and concurrently linked 2012  NHIS–HUD participants, 

by percentage of households with disabled or elderly persons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

IV.   All 2012 HUD-assisted tenants and concurrently linked 2012  NHIS–HUD participants,

by household characteristics .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   . 28

V.  

All 2009–2012 HUD-assisted tenants and concurrently linked 2009–2012  NHANES–HUD 

participants, by HUD housing category . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 

VI.   All 2009–2012 HUD-assisted tenants and concurrently linked 2009–2012  NHANES–HUD 

participants, by sex and age group.   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   . 30

VII.   All 2009–2012 HUD-assisted tenants and concurrently linked 2009–2012  NHANES–HUD  

participants, by percentage of households with disabled or elderly persons  . . . . . . . . . . . . . . . . . . . . . . . . . 31

VIII.   All 2009–2012 HUD-assisted tenants and concurrently linked 2009–2012  NHANES–HUD 

participants, by household characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

iv

Acknowledgments

The authors gratefully acknowledge 

the following persons for their 

contributions to the success of the 

National Center for Health Statistics 

(NCHS)–U.S. Department of Housing 

and Urban Development (HUD) data 

linkage project: Peter Meyer, Sonali 

Sinha, and Pei-Lu Chiu of NCHS for 

previous research in linking National 

Health Interview Survey and HUD data; 

Clinton Thompson, Deborah Ingram, and 

Eric Miller of NCHS for careful review 

and feedback on the report; Dean Judson 

of NCHS for methodological guidance in 

developing the linkage-eligible adjusted 

sample weights; Fred Selck of NCHS 

for leading the data linkage project 

during its early stages; Jesse Bassich of 

NCHS for programming assistance; Lynn 

Rodgers and Pramod Pamnani of HUD 

for programming expertise in creating 

the HUD administrative data file; Lydia 

Taghavi of HUD for programming 

support; Brent Mast and Carol Leming of 

HUD for providing input on the contents 

of the linked file; Donna Miller and Eve 

Powell-Griner of NCHS for providing 

input on confidentiality and privacy of 

linked survey participants; and Amy 

Branum and Makram Talih of NCHS 

for their careful review of this report. 

The authors gratefully acknowledge the 

editorial staff for their critical review 

and preparation of this report, which was 

edited and produced by the NCHS Office 

of Information Services, Information 

Design and Publishing Staff: Jane Sudol 

edited the report, and typesetting and 

graphics were done by Odell D. Eldridge 

(contractor).

v

Abstract

Background

The National Center for Health 

Linkage of 1999–2012 National 

Statistics (NCHS) provides statistical 

information to guide actions and 

Health Interview Survey and 

policy to improve the health of 

the American people. NCHS has 

developed a data linkage program 

National Health and Nutrition 

that links its cross-sectional health 

survey data to information from vital 

Examination Survey Data to 

and administrative data sources. 

Through a collaborative interagency 

agreement between NCHS and 

U.S. Department of Housing 

the U.S. Department of Housing 

and Urban Development (HUD), 

participants in two national health 

and Urban Development 

surveys administered by NCHS were 

linked to administrative data from HUD.

Administrative Records

Methods

by Patricia C. Lloyd, National Center for Health Statistics; Veronica E. 

This report describes and 

Helms, U.S. Department of Housing and Urban Development; Alan E. 

evaluates the data linkage of 

Simon, Cordell Golden, James Brittain, Eileen Call, and Lisa B. Mirel, 

1999–2012 National Health Interview 

National Center for Health Statistics; Barry L. Steffen, Jon Sperling, 

Survey (NHIS) and National Health 

and Nutrition Examination Survey 

and Elizabeth C. Rudd, U.S. Department of Housing and Urban 

(NHANES) to administrative records 

Development; Jennifer D. Parker, National Center for Health Statistics; from HUD through 2014. A brief 

and Carol S. Star, U.S. Department of Housing and Urban Development

overview of the data sources, 

methods used for linkage, details of 

the resulting linked data files, and 

analytic considerations are provided.

Introduction

interagency agreement between NCHS 

and the U.S. Department of Housing and 

Conclusions

Urban Development (HUD), participant 

The National Center for Health 

The NCHS–HUD linkage 

records from these two NCHS surveys 

Statistics (NCHS) is the nation’s principal 

demonstrates the feasibility of linking 

were linked to administrative data from 

agency providing health statistics to 

population health survey data to 

HUD’s largest federal housing assistance 

identify and address health issues. To 

administrative records from federal 

programs, which include Housing Choice 

maximize the scientific value of NCHS 

programs and enhances two NCHS 

Vouchers (HCVs), multifamily (MF), and 

population-based surveys, the agency 

population health surveys, NHANES 

public housing (PH) programs. The HUD 

and NHIS, by al owing examination of 

has developed a data linkage program 

administrative files contain housing, 

the relationship between housing and 

that links health survey data to vital 

income, and household characteristics 

health.

and administrative data sources. Linked 

as well as program participation data for 

data files enable researchers to use 

HCV, MF, and PH program recipients in 

Keywords: record linkage • linked 

longitudinal data from administrative 

all 50 states and the District of Columbia. 

data • HUD • housing • NHIS • 

databases or mortality data in 

NHANES

This report summarizes the data 

combination with cross-sectional data 

sources and linkage methods used to 

to examine and provide more insight on 

create the linked NCHS–HUD data 

factors that influence disability, health 

files. It provides linkage rates for the 

care utilization, morbidity, and mortality 

1999–2012 NHIS–HUD and NHANES–

among different U.S. subpopulations. 

HUD linked files and the percentage 

Two NCHS national health 

distribution of selected characteristics 

surveys—the National Health Interview 

among linked survey participants. 

Survey (NHIS) and the National 

Appendix I contains a summary of 

Health and Nutrition Examination 

the HUD programs included in linked 

Survey (NHANES)—monitor the 

data sets. Appendix II summarizes the 

health and well-being of the civilian 

contents of the linked NCHS–HUD data 

noninstitutionalized population of the 

files. Appendix III provides details about 

United States. Through a collaborative 

the files and a description of some key 

Page 1 

Page 2   Series 1, No. 60

variables for researchers to consider 

utilization, health insurance, and income 

examinations and health measurements 

when using the linked NCHS–HUD data.  and assets. 

are performed in a specially designed 

Appendix IV describes an evaluation 

From each family, one sample adult 

and equipped mobile examination center 

comparing characteristics among linked  

(not necessarily the head of household) 

(MEC), which travels to locations 

2012 NHIS–HUD and 2009–2012 

and one sample child (if any children 

throughout the country. The study team 

NHANES–HUD participants to those of 

under age 18 years are present) are 

consists of a physician, medical and 

HCV, MF, and PH program recipients, 

randomly selected, and detailed survey 

health technicians, and dietary and health 

using HUD administrative data from the 

data are collected on specific health 

interviewers. 

same time period.

topics using the Sample Adult Core and 

The NHANES interview includes 

the Sample Child Core questionnaires. 

demographic, socioeconomic, dietary, 

Data Sources

Data for the Sample Child questionnaire 

and health-related questions. The 

is obtained from a knowledgeable adult 

examination component consists of 

in the household, usually a parent.

medical, dental, and physiological 

NHIS

Data are collected through a 

measurements, as well as laboratory tests. 

personal household interview conducted 

Survey findings are used to determine 

NHIS is a cross-sectional household 

by interviewers employed and trained 

the prevalence of major diseases and risk 

interview survey designed to monitor the  by the U.S. Census Bureau according factors for diseases. NHANES findings 

health of the civilian noninstitutionalized  to procedures specified by NCHS. A are also the basis for national standards 

U.S. population through the collection 

computer-assisted personal interviewing 

for such measurements as height and 

and analysis of data on a broad range of 

(CAPI) mode using a laptop computer 

weight and for national growth charts. 

health topics (1). NCHS has conducted 

has been used since 1997. For more 

Data are also collected on chronic and 

NHIS continuously since 1957, and the 

information on NHIS, visit: https://www.

previously undiagnosed conditions. 

content of the survey is periodically 

cdc.gov/nchs/nhis.htm. 

More information on NHANES is 

updated. The sampling plan follows a 

available from: https://www.cdc.gov/

multistage area probability design that 

NHANES

nchs/nhanes.htm.

permits the representative sampling of 

households and noninstitutional group 

NHANES utilizes interviews, 

HUD Administrative Data

quarters (e.g., college dormitories). The 

laboratory tests, and physical 

sampling plan is redesigned after every 

examinations to assess the health 

HUD’s largest housing assistance 

decennial census. The NHIS 1995–2005 

and nutritional status of civilian 

programs, which include Housing Choice 

survey design oversampled black as well 

noninstitutionalized adults and 

Vouchers (HCVs), multifamily (MF) 

as Hispanic persons; the 2006–2012 

children in the United States (3). The 

programs, and public housing (PH) 

design oversampled black, Hispanic, and 

survey currently includes a nationally 

programs, are included in the linked 

Asian persons (2). 

representative sample of about 5,000 

NCHS–HUD data. MF programs provide 

Demographic and basic health 

persons in about 15 counties across 

affordable housing through contracts 

information are collected on everyone 

the country each year. Oversampled 

with private owners of apartment 

in the household. For the years of data 

subgroups for 1999–2006 included 

buildings. HCV and PH programs 

used for linkage, the Core questions 

non-Hispanic black as well as Mexican-

are managed by local public housing 

have remained largely unchanged. 

American persons; low-income persons 

agencies (PHAs), which oversee data 

This allows for trend analyses and 

of non-Hispanic white and other race and  collection and manage housing assistance for data from more than 1 year to be 

ethnicity (beginning in 2000); adolescents  program implementation. Buildings of pooled to increase sample size for 

aged 12–19; and non-Hispanic white 

PH programs are owned by PHAs. The 

analytic purposes. For 1999–2012 

and other persons aged 70 and over. 

HCV program gives tenants a voucher 

NHIS, the Core section contains four 

Oversampled subgroups for 2007–2010 

that covers part of their rent in a private-

major components: Household, Family, 

included all Hispanic as well as non-

market unit. Administrative data for 

Sample Adult, and Sample Child. The 

Hispanic black persons; low-income 

HUD-assisted households are submitted 

Household component collects limited 

persons of non-Hispanic white and other 

by housing providers. Additional 

demographic information on all of the 

race and ethnicity; and non-Hispanic 

information about these programs is 

individuals in a particular household. The  white and other persons aged 80 and 

provided in Appendix I and the Analytic 

Family component verifies and collects 

over (4,5). Beginning with the NHANES  Guidelines (7).

additional demographic information on 

2011–2012 cycle, non-Hispanic Asian 

each member from each family in the 

persons were also oversampled in 

household and collects data on topics 

addition to the ongoing oversample of 

including health status and limitations, 

subgroups from 2007–2010 (6).

injuries, health care access and 

Health interviews are conducted 

in participants’ homes. Physical 

Series 1, No. 60   Page 3 

Public and Indian Housing 

administrative records included in the 

MF programs, or PH programs. More 

Information Center 

Transaction File were restricted to MF 

information about HUD eligibility 

program transactions occurring June 30, 

criteria is available from the HUD 

Local PHAs collect and 

1996–December 31, 2014, and HCV 

website: https://www.huduser.gov/portal/

electronically submit information 

and PH program transactions occurring 

home.html.

to the Public and Indian Housing 

December 1, 1999–December 31, 2014. 

The process for determining linkage 

Information Center (PIC) for households 

These program transaction periods are 

eligibility and collecting personally 

receiving HCVs or PH assistance. Each 

referred to as the linked NCHS–HUD 

identifiable information (PII) varied 

occasion that data are entered into the 

administrative period.

by NCHS survey and year (cycle). For 

system is referred to as a transaction. 

NHANES, PII was consistently collected 

The administrative purpose of the 

during the time frame used for linkage, 

periodic transactions is to ensure that 

Data Linkage 

but the process for obtaining consent 

tenant rent contributions, which are 

Approval, Eligibility,  for record linkage varied across the 

based on income, are determined 

survey cycles. For 1999–2008 NHANES 

accurately. Information collected on the 

and Process 

participants, refusal to provide an SSN 

administrative forms include: dates of 

was considered an implicit refusal 

enrollment and participation, program 

for record linkage. For 2009–2012 

recertification, family characteristics, 

Linkage Approval and 

NHANES, participants were explicitly 

detailed income and asset information 

Eligibility

asked for consent to be included in record 

for all household members, and an 

linkage activities during the informed 

estimate of the family's anticipated income 

All NCHS data linkage activities are  consent process prior to interview. 

for the next 12 months, including sources 

reviewed and approved by the NCHS 

Participants who provided an affirmative 

of that income. More information about 

Research Ethics Review Board (ERB). 

response to the linkage question were 

recertification for HCV and PH programs is  The NCHS Research ERB, which 

considered linkage-eligible, conditional 

available from the Analytic Guidelines (7).

functions similar to an Institutional 

on having sufficient PII.

Review Board (IRB), is an appointed 

For NHIS, changes over time in the 

Tenant Rental Assistance 

ethics review committee that ensures 

process for collecting PII and the addition 

Certification System

research involving human participants 

of a question to obtain explicit consent 

and the welfare of study participants 

for linkage meant that the criteria for 

Owner/agents and contract 

conform to federal regulations. The 

linkage eligibility varied by survey year. 

administrators of MF units collect and 

NCHS–HUD linkage was reviewed and 

For 1999–2006, the full nine-digit SSN 

electronically submit information to HUD  approved by the NCHS Research ERB.

(SSN9) was requested. For 1999–2001, 

through the Tenant Rental Assistance 

Survey data and HUD administrative  SSN9 was requested for all NHIS 

Certification System (TRACS). As with 

records were linked only for NCHS–

participants. For 2002–2003, SSN9 was 

PIC, TRACS collects dates of enrollment 

HUD linkage-eligible survey participants.  requested for only the family respondent. 

and participation, program recertification, 

NCHS determined eligibility for this 

For 2004–2006, SSN9 was requested 

detailed income and asset information for 

linkage based on whether the survey 

for the NHIS family respondent, sample 

all household members, and an estimate 

participant provided certain data elements  adult, and sample child. For these years, of the family's anticipated income for the 

necessary for linkage, including Social 

if participants refused to provide SSNs, 

next 12 months, including sources of that 

Security number (SSN), sex, month of 

they were implicitly considered to have 

income. Also like PIC, each occasion that 

birth, year of birth, first name, and last 

refused record linkage. During that time 

data are entered into the system is referred  name; did not refuse data linkage; and period, the refusal rate for providing 

to as a transaction. More information 

did not refuse to respond to questions 

SSN increased, which reduced the 

about TRACS and recertification for MF 

about receiving rental assistance (NHIS 

number of NHIS participants eligible 

programs is available from the Analytic 

only). The question about receiving rental  for record linkage (8). In an attempt to Guidelines (7).

assistance was asked only of families 

counter the decline in linkage eligibility 

reporting that they lived in a rental 

rates, research was conducted at NCHS 

HUD transaction dates included  property. Very few families living in a to assess the accuracy of National 

in NCHS–HUD administrative 

rental property refused to answer the 

Death Index matches using partial SSN 

period

question about receiving rental assistance  and other PII. The research assessed (less than 1% in each of the 1999–2012 

algorithms using the last four and last 

For the linkage described in 

NHIS survey years). NCHS–HUD 

six digits of SSNs. The results provided 

this report, HUD programming staff 

linkage eligibility is distinct from HUD 

sufficient evidence to support changes in 

created an extract of HUD transactions 

program eligibility; the latter defines 

how NHIS collected SSNs for linkage 

for recipients of HCV, MF, and PH 

whether a person meets eligibility criteria  (9). Beginning in 2007, NHIS attempted programs based on PIC and TRACS, 

to receive HUD housing assistance 

to decrease linkage refusal rates by 

referred to as the Transaction File. HUD 

through HCVs and related programs, 

adding a short introduction before asking 

Page 4   Series 1, No. 60

for SSN during the interview, requesting 

Linkage Process

Medicare Health Insurance Claim (HIC) 

only the last four SSN digits (SSN4) 

number, if provided. SSN9 was extracted 

instead of all nine and asking participants 

Figure 1 presents the overall process  from the Medicare HIC number only for their explicit permission to link to 

for linking NCHS survey data to HUD 

if the survey participant was identified 

administrative records if SSN4 had not 

administrative data. HUD provided a 

as the primary claimant for Medicare 

been provided (8). Also at this time, the 

data file, referred to as the HUD finder 

benefits. 

NCHS Research ERB determined that 

file, containing PII (e.g., SSN, first and 

The linkage was predominantly 

for NHIS 2007 forward, only primary 

last name, sex, date of birth, a unique 

deterministic or rules-based, meaning that 

respondents (sample adult and sample 

HUD-created identification [ID], and 

a set of criteria had to be met for a pair 

children) would be eligible for linkage to  a sequence number to identify specific of records to be linked. Two approaches 

administrative records. 

transactions) of individual HCV, MF, 

were used to link NCHS survey data to 

NCHS survey participants under 

or PH program recipients. NCHS staff 

HUD administrative records. The first 

age 18 at the time of the survey are 

verified that the SSNs on the HUD files 

approach was used for NCHS survey 

considered linkage-eligible if the above-

were valid before linking to a file of 

years when the SSN9 was collected from 

mentioned linkage eligibility criteria 

1999–2012 NHIS and NHANES linkage-

survey participants (1999–2006 NHIS 

are met and consent is provided by 

eligible survey participants. For example,  and all NHANES cycles). This approach their parent or guardian at the time of 

if an SSN contained fewer than nine 

linked survey participants to HUD 

the survey. Once the child participant 

digits; nonnumeric values; the first three 

administrative records by matching on 

becomes an adult, however, they do not 

digits “000,” “666,” or in the 900 series; 

valid SSN9, year of birth, month of birth, 

have the opportunity to provide or deny 

the second group of two digits as “00”; or  and sex. 

consent for linking their survey data 

the third group of four digits as “0000,” 

The second approach accommodated 

to administrative data based on their 

it was not considered valid. For survey 

the NHIS survey years when SSN4 

experience as an adult. In accordance 

participants who did not provide a valid 

was collected. This approach matched 

with NCHS Research ERB guidelines, 

SSN yet did not refuse to provide their 

on SSN4, year of birth, month of birth, 

the linked NCHS–HUD data of child 

SSN, SSN9 was extracted from their 

sex, first name, last name, and day of 

participants are available only for 

records that occurred prior to the survey 

participant’s 18th birthday. For example, 

a 15-year-old linkage-eligible survey 

participant of NHIS 2005 can be linked to 

NCHS survey data

HUD administrative records. Linked data 

containing HUD administrative data for 

2007 and earlier years could be accessed 

by a researcher and included in analyses 

because the child survey participant 

would have been under age 18 during this 

time. However, NCHS is not authorized 

Eligible for linkage

Ineligible for linkage

to provide researchers access to HUD 

administrative records for that child 

survey participant from 2008 through 

HUD finder file:

2012 because the child survey participant 

– HUD unique identification 

would have been aged 18 or older. 

     number

Table 1 presents the total number of 

– Social Security number

Data linkage

Nonmatched records

– Last name

1999–2012 NHIS participants for each 

– First name

survey year and age group (0–17 years, 

– Date of birth

18–39, 40–64, and 65 and over), the 

– Sex

number who were eligible for linkage, 

the percentage eligible out of the total 

sample, the number who were linked, 

Matched records

and the percentage who were linked out 

of those eligible for linkage. Data are 

presented for all NHIS participants, both 

sample adults and sample children. Table 

NOTE: NCHS is National Center for Health Statistics; HUD is U.S. Department of Housing and Urban Development.

SOURCES: NCHS, National Health Interview Survey and National Health and Nutrition Examination Survey, 1999–2012, 

2 shows similar results for 1999–2012 

data linked to HUD administrative records, 1996–2014.

NHANES participants. Data are presented 

for all NHANES participants and for 

Figure 1. Process used to link National Center for Health Statistics survey data to those who were examined in the MEC.

U.S. Department of Housing and Urban Development administrative data sources

Series 1, No. 60   Page 5 

birth, thus incorporating first and last 

records were used for each linkage-

concurrency files, seven separate episode 

names and day of birth into the matching  eligible NCHS survey participant based files, and a weights file, are available only 

criteria. Agreement on first name and 

on variations of names. HUD records 

through the NCHS Research Data Center 

last name was based on exact spelling 

could be matched to any or all of the 

(RDC). Appendix Table I describes 

matches or, because spelling variants 

submission records created for a survey 

each of the files that compose the linked 

of names are common, was based on 

participant. For example, the name 

NCHS–HUD data. Data documentation, 

the way a name sounds rather than how 

“Beth” may be a nickname for a formal 

including the Analytic Guidelines (7) and 

it is spelled. The sound-alike systems 

name like “Elizabeth.” In this situation, 

Data Dictionary (11), feasibility files, 

included both a variation of the New 

a record for “Beth” and a record for 

and sample read-in software programs to 

York State Identification Intelligence 

“Elizabeth” were created and submitted 

import the feasibility files, can be found 

System (NYSIIS) and the Soundex 

for linkage.

on the NCHS website: https://www.cdc.

algorithm (10). NYSIIS converts a name 

Once the linkage was performed 

gov/nchs/data-linkage/hud.htm. Details to a phonetic coding. For example, 

and the best-matched record was 

about each of the linked files are provided 

records with last names Smith and 

selected, NCHS created an NCHS finder 

in the following section.

Smyth received equivalent NYSIIS 

file containing the HUD-created ID 

codes, and both would be selected as a 

and binary indicator flags for survey 

NHIS–HUD and NHANES–

potential match for an NCHS submission  participants who were linked to the HUD  HUD public-use feasibility files with Smith (or Smyth) as a last name. 

administrative files for HCV, MF, or 

Similarly, Soundex is a phonetic 

PH program recipients through 2014. 

NCHS created the 1999–2012 

algorithm for indexing names by sound, 

This file was delivered to HUD, and 

NHIS–HUD public-use feasibility file 

as pronounced in English. The goal is for  HUD programming staff prepared and and the 1999–2012 NHANES–HUD 

homophones to be encoded to the same 

delivered to NCHS a single transactions-

feasibility file, which can be downloaded 

representation so that they can agree 

level file containing data summarized 

directly from the NCHS website and 

despite minor differences in spelling. 

for the person’s household as well as 

merged with public-use NHIS and 

Specifically, the second approach linked 

data summarized for the individual HUD  NHANES data, respectively. 

survey participants to administrative 

housing assistance recipients who were 

The feasibility files contain data on 

records based on matching the last four 

linked to NCHS survey participants. 

survey participants’ linkage eligibility 

digits of SSN, year of birth, month of 

NCHS programming staff ensured 

status for the NCHS–HUD linkage, 

birth, sex, and meeting at least one of the  that all linked survey participants final match status, and whether the 

following conditions:

identified in the linkage process were 

survey participant ever participated in 

returned in the transaction file. NCHS 

HCV, MF, or PH programs. A survey 

● Soundex of first names and last 

staff edited the HUD Transaction File to 

participant is classified as “ever receiving 

names agree and are not missing 

resolve discrepancies with linked records  HUD housing assistance” if the survey 

● NYSIIS of first names and last 

so that the final transaction file met ERB 

participant was linkage-eligible and 

names agree and are not missing

guidelines. The final linked transaction 

had at least one transaction in the HUD 

● Soundex of nonmissing first names 

file served as the basis for creating the 

administrative database during the 

agree and day of birth agree 

linked files. 

linked NCHS–HUD administrative time 

● Soundex of nonmissing last names 

period. Also provided are three variables 

agree and day of birth agree 

representing ever participation in HCV, 

● NYSIIS of nonmissing first names 

Linked NCHS–HUD  MF, or PH programs during the linked 

agree and day of birth agree 

Data

NCHS–HUD administrative time period. 

● NYSIIS of nonmissing last names 

Program participation is not mutually 

agree and day of birth agree 

exclusive across the administrative 

● Soundex first name agrees with 

General Description of 

period. For example, a person may 

Soundex last name and Soundex 

receive assistance as an MF program 

last name agrees with Soundex first 

Linked Data Files 

recipient and then receive an HCV during 

name 

the linked NCHS–HUD administrative 

● NYSIIS first name agrees with 

The linked NCHS survey data and 

period.

NYSIIS last name and NYSIIS last 

HUD administrative data were used 

The feasibility files can be used to 

name agrees with NYSIIS first name

to produce 12 separate data files. Two 

public-use feasibility files, one for 

determine the maximum available sample 

NCHS participants whose data fields  the 1999–2012 NHIS and one for the 

size to assess the feasibility of conducting 

matched the equivalent administrative 

1999–2012 NHANES, are available on 

analyses using the linked NCHS–HUD 

fields using either of the two approaches 

the NCHS data linkage website:  

data by allowing researchers who are 

were identified as linked records. 

https://www.cdc.gov/nchs/data-linkage/

developing NCHS RDC proposals 

To increase the likelihood of finding 

index.htm. Ten restricted-use files, to determine if sufficient numbers of 

a match, multiple or alternate submission  consisting of the transaction and individuals and sufficient degrees of 

freedom exist in the category of interest 

Page 6   Series 1, No. 60

among those that have been successfully 

NCHS–HUD restricted-use 

of enrollment in a HUD program and is 

linked to HUD administrative data. 

transaction file

characterized by a start date and an end 

These publicly available files also make 

date. A graphical depiction of an episode 

it possible to identify demographic 

The transaction file contains a record  is presented in Figure 2.

and health status variables available in 

for each HUD administrative transaction 

Seven episode files contain start 

the corresponding survey public-use 

of the linked 1999–2012 NHIS–HUD and  and end dates for participation episodes. 

data through subdividing the survey 

NHANES–HUD participants, and may 

One file is for all HUD programs overall, 

sample, calculating estimates of numbers  contain more than one record per person.  and six additional files are for HUD 

of people in categories of interest, 

The transaction file contains detailed 

subprograms based on the transaction 

and determining cell sizes by related 

member and household attributes that 

data and assumptions about reasonable 

categories. 

are contained in HUD administrative 

intervals between transactions (Appendix 

Note that the feasibility files do not 

systems. Transactions for child 

Table I). Most HUD housing assistance 

contain data pertaining to the timing 

participants that occurred after the child’s  recipients are required to recertify each of HUD assistance or details about the 

18th birthday were removed during 

year, and consequently, a transaction 

housing unit; instead, they contain record  postprocessing, per ERB guidance.

is expected each year. However, some 

status variables and record counts to 

HUD programs have longer intervals 

assist researchers who are considering 

NCHS–HUD restricted-use 

between recertifications. The episode 

whether to initiate an RDC proposal. 

episode files

files are useful primarily for longitudinal 

Researchers should be aware that all 

analysis related to the duration and 

NCHS surveys linked to the HUD 

To facilitate analyses using the 

timing of housing assistance episodes, 

administrative data have complex survey 

linked files, episode files were created 

and conditions or outcomes that may 

designs. Therefore, considerations of 

with a single record per person containing  have pre-existed or occurred after such sample size and statistical power should 

the start and end dates for each period 

episodes.

take into account the survey design to 

of continuous enrollment, or episode. 

produce statistically reliable analyses (2,6).

An episode is a single continuous period 

SP1

SP2

SP3

1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014

NOTES: The figure shows three possible scenarios related to the temporal alignment of the linked survey and housing assistance data for three hypothetical survey participants (SPs). In each timeline, the arrow represents the year of the National Center for Health Statistics (NCHS) survey, and the rectangular box represents the time period (episode) during which the SP

received housing assistance from the U.S. Department of Housing and Urban Development (HUD). SP1 received HUD assistance after his or her interview, SP2 received HUD

assistance before his or her interview, and SP3 received HUD assistance concurrent with his or her interview.

SOURCES: NCHS, National Health Interview Survey and National Health and Nutrition Examination Survey, 1999–2012, data linked to HUD administrative records, 1996–2014.

Figure 2. Temporal alignment of National Center for Health Statistics surveys linked to U.S. Department of Housing and Urban Development administrative data files

Series 1, No. 60   Page 7 

NCHS–HUD restricted-use 

Table 3 presents the number and 

SUDAAN software package (Procedure 

concurrency file 

percentage of NHIS and NHANES linked  WTADJUST or WTADJX) (16) was 

participants who received HUD housing 

used to adjust the statistical weights for 

The NCHS–HUD concurrency file 

assistance concurrently, within 1, 2, and 

nonresponse with auxiliary information, 

is a restricted-use file that contains a 

3 years of their survey interview. Data 

specifically age, race and ethnicity, and 

single record for each linked participant 

are presented by survey year and age at 

sex. NCHS provides adjusted sample 

and summarizes information based on 

the time of interview (0–17 years, 18–39,  weights in a weights file based on this timing of housing assistance relative to 

40–64, and 65 and over). 

approach to account for differences 

the date of the NCHS survey interview 

in characteristics among linkage-

or examination. This file includes all 

NCHS–HUD restricted-use 

eligible and linkage-ineligible survey 

linked survey participants, whether 

participants. Because inferences may 

they were classified as concurrent 

sample weights file

depend on the approach used to adjust 

or nonconcurrent. A linked survey 

The weights file contains a record 

sample weights—within SUDAAN’s 

participant is classified as concurrent 

for each 1999–2012 NHIS and NHANES  WTADJUST or using a different 

if he or she was administered their 

participant who was linkage-eligible, and  calibration approach—researchers NCHS survey interview or examination 

contains five sample weights (sample 

are advised to seek assistance from a 

between the start and end dates of a HUD  adult weight, sample child weight, and mathematical statistician for guidance on 

assistance episode. A graphical depiction 

person weight for NHIS, and interview 

their particular project. Note that other 

of a survey participant who concurrently 

weight and MEC weight for NHANES) 

approaches to calculating weights or 

received HUD assistance at the time of 

that correspond to the survey and are 

handling possible linkage-eligibility bias 

the survey (SP3) is provided in Figure 2. 

adjusted for linkage eligibility. All 

with other statistical software packages 

A nonconcurrent participant would have 

linkage-ineligible survey participants 

can be used. More information about the 

partaken in the NCHS survey at some 

are given a weight of zero. The linkage 

eligibility-adjusted survey weights can be 

point outside of their HUD assistance 

eligibility-adjusted sample weights were 

found in the Analytic Guidelines (7).

episode (SP1 and SP2 in Figure 2). 

derived using a model-based calibration 

The concurrency file enables 

approach. 

researchers to determine whether linked 

Access to Linked NCHS–

The sample weights provided in the 

survey participants concurrently received  NCHS population health survey data HUD Data Files 

HUD housing assistance at the time of 

files adjust for oversampling of specific 

the NHIS or NHANES interview or 

subgroups and differential nonresponse. 

Due to confidentiality requirements, 

NHANES examination. Several factors 

The sample weights are poststratified 

NCHS restricts the availability of linked 

influence the temporal alignment of 

to annual population totals for specific 

NCHS–HUD data files to researchers 

the survey and administrative data, 

population domains to provide nationally  who have approved research proposals including age of the survey participant, 

representative estimates (2,12–14). 

through NCHS RDC, with the exception 

HUD program eligibility, discontinuous 

Previous research suggests that survey 

of the NCHS–HUD feasibility files 

program coverage, and residential 

participants who provide sufficient PII 

(available from: https://www.cdc.gov/

mobility of the survey participants. 

for linkage are not a random sample 

nchs/data-linkage/hud-feasibility.htm). 

More information about the concurrency 

of survey participants. For some 

More information regarding RDC and 

variables is provided in Appendix III.

characteristics, linkage-eligible survey 

instructions for submitting an RDC 

For researchers interested in 

participants may differ systematically 

proposal are available from:  

examining the timing of HUD assistance 

from survey participants who are not 

https://www.cdc.gov/rdc/.

for nonconcurrent linked participants, the  linkage-eligible; failing to account for number of days between the interview 

linkage eligibility when examining 

Analytic 

date and the end date of their most recent  these differences may lead to biased HUD episode was calculated, as well as 

results (15). Analyses using the linked 

Considerations

the number of days between the interview  NCHS–HUD data should include only date and the start date of their next 

linkage-eligible survey participants rather 

This section highlights general 

HUD episode. Although these variables 

than the full survey sample, and NCHS 

considerations and guidelines for analysis 

cannot be accessed directly by the 

recommends using sample weights that 

when using the linked data files; more 

researcher, researchers can request their 

are adjusted for linkage eligibility. 

detailed information can be found in 

own categories in their RDC proposal, 

To adjust for the potential bias that 

the Analytic Guidelines (7). These 

based on the number of days between 

may result from differences between the 

general considerations do not replace 

the NCHS interview or examination and 

linkage-eligible and linkage-ineligible 

the guidance for analyzing data from 

a HUD transaction. More information 

populations, the linked NCHS–HUD 

NHIS and NHANES. NCHS encourages 

about these timing variables is provided 

data contain linkage-eligibility adjusted 

researchers who discover new analytic 

in Appendix III.

weights. A model-based calibration 

issues during the course of their analysis 

approach developed within the 

Page 8   Series 1, No. 60

of the linked data to report them to 

Careful consideration is needed when  comparison between the population of 

the NCHS Data Linkage Program via 

examining characteristics among NCHS–

linked survey participants and the overall 

datalinkage@cdc.gov.

HUD linked participants and defining an 

population of HUD housing assistance 

As part of a researcher’s proposal 

analytic sample of linked participants. 

recipients is presented in Appendix IV.

to RDC, restricted variables from NCHS 

Although some characteristics (e.g., sex 

Descriptive statistics for 2008–2012 

surveys and variables from the HUD files  or race and ethnicity) are not likely to NHIS and 2009–2012 NHANES 

need to be specifically requested within 

change over time or be associated with 

participants and linked survey 

the same proposal. For more information 

receipt of HUD housing assistance, 

participants from those same surveys are 

about restricted-use NCHS survey 

other characteristics (e.g., type of health 

presented in Tables 4–7. Children (aged 

data, visit: https://www.cdc.gov/rdc/

insurance coverage or poverty status) 

0–17 years) and adults (aged 18 and 

b1datatype/dt122.htm. In the proposal, may differ because these characteristics 

over) are presented separately. Summary 

the researcher provides a file containing 

are associated with receipt of HUD 

statistics for the linked NHIS–HUD data 

variables from the public-use NCHS 

housing assistance. As a result, survey 

are presented in Tables 4 and 5; linked 

survey data to RDC for merging with the 

participants who were linked at any time 

NHANES–HUD summary statistics are 

requested restricted variables from NCHS  during the administrative period and 

shown in Tables 6 and 7. The sample 

surveys and the linked NCHS–HUD file 

those who were receiving HUD housing 

weights used in preparing the summary 

variables. An RDC staff member verifies 

assistance at the time of their survey 

statistics are those in the weights file 

the full list of variables (restricted and 

interview or examination may differ for 

and are adjusted for linkage eligibility 

public-use) and consults with the data 

several characteristics.

as described previously. Researchers 

divisions at NCHS that are responsible 

When combining years of survey 

should be aware that applying different 

for producing the files, as well as with 

data, NCHS recommends that researchers  analytic approaches (i.e., variable the NCHS confidentiality office to ensure  assess the assumption of no trend in parameterization and alternative 

that no potential disclosure risk of survey  the estimates of the research variables approaches to weight adjustment) may 

participants exists. A description of 

of interest over the time periods being 

result in findings different from those 

selected variables that may be useful in 

combined, including trends in the receipt 

presented below. 

analyses of the linked NCHS–HUD data 

of housing assistance, and changes in the 

The following criteria were used 

files is included in Appendix III.

quality of the HUD administrative data 

to assess similarities and differences 

that may affect their study results.

in the selected sociodemographic and 

Sample Weights

health characteristics between linked 

Descriptive Analyses  participants and the survey population:

All proposals to use the linked data 

should request the correct sample weight 

of Linked NHIS–HUD  1.  If the percentage for each 

to be used. The weights file contains a 

category (e.g., male or female) of 

single record for all survey participants of  and NHANES–HUD 

a characteristic (e.g., sex) is equal 

1999–2012 NHIS and NHANES, as well 

Participants

for both linked participants and the 

as adjusted sample weights from NHIS 

survey population, it is described as 

(person weight, sample adult weight, 

being the same. 

and sample child weight) and NHANES 

The linked NCHS–HUD data 

2.  If the relative difference between 

(interview weight and MEC weight). See  allow for many different analyses, 

the linked sample and the survey 

the Data Dictionary for more information  but note that the population of linked population, defined as: 

about these variables (11).

survey participants may differ from 

     | Xpopulation – Xlinked | / Xpopulation 

both their respective survey populations 

Analyses Using Linked 

as well as the overall population of 

is between 0.0 and 0.1 for all 

NCHS–HUD Data

HUD housing assistance recipients. 

categories of the characteristic, the 

Survey participants who were linked 

linked sample is described as being 

NCHS recommends that researchers 

to the HUD administrative data may 

“consistent or similar” to the survey 

using the linked NCHS–HUD data 

not be representative of the larger 

population with respect to that 

combine survey years to increase sample 

survey populations and differ by certain 

characteristic. 

size, if needed. Consult the analytic 

characteristics, such as poverty status, 

3.  If the relative difference between 

guidelines for NHANES (6,17) and NHIS  that would make them more likely to 

the linked sample and the survey 

(18,19) for instructions on combining 

receive HUD housing assistance. This 

population for at least one category 

years. Even though the survey periods for  section provides a brief descriptive of the characteristic is 0.1 or greater, 

the linked 1999–2012 NHIS–HUD and 

analysis of the linked NHIS–HUD and 

the linked sample is described 

NHANES–HUD data files overlap, data 

NHANES–HUD participants and their 

as being “different (higher/more 

from the two surveys should be analyzed 

similarities to and differences from 

or lower/less)” than the survey 

separately. 

their respective survey populations. A 

population with respect to that 

characteristic.

Series 1, No. 60   Page 9 

 Because the two populations (linked  child survey participants that were male of HUD housing assistance recipients 

participants and the survey population) 

(49.1%) and female (50.9%) were similar  because of the sample design of the were not statistically independent and 

to the percentages among the NHANES 

surveys, which include only the civilian 

measures of correlation between the two 

population aged 0–17 years (males 

noninstitutionalized U.S. population. In 

populations were not readily available, 

50.7%, females 49.3%). However, the 

Appendix IV,  characteristics of the linked 

comparisons were not statistically tested.

distributions of age, race and ethnicity, 

sample and the entire HUD-assisted 

Descriptive statistics for 2008–2012 

poverty status, health status, and health 

population are presented to illustrate 

NHIS child participants and linked child 

insurance coverage differed between the 

similarities and differences between 

survey participants are presented in 

two populations. More of the linked child  linked survey participants and the entire 

Table 4. The percentages of the linked 

survey participants were aged 12–17 

population receiving HUD assistance. 

child survey participants that were 

years (40.6% compared to 34.5%) and 

male (49.6%) and female (50.4%) were 

non-Hispanic black (45.8% compared 

Conclusion 

similar to the percentages among the 

to 14.2%), and had family incomes 

NHIS population aged 0–17 years (males  that were below the poverty threshold 51.1%, females 48.9%). However, the 

(61.0% compared to 23.5%). Compared 

The linked NCHS–HUD data are 

distributions of age, race and ethnicity, 

to NHANES child participants, linked 

the first NCHS linked data product 

poverty status, health status, and health 

child survey participants had a higher 

combining health and housing assistance 

insurance coverage differed between 

percentage with fair or poor health 

data and stem from an interagency 

the two populations. Compared to the 

(7.1% compared to 4.3%) and a lower 

collaboration between NCHS and HUD. 

population of NHIS child participants, 

percentage with no health insurance 

These data provide information about 

more of the linked child survey 

coverage (5.5% compared to 8.0%).

health characteristics of persons who 

participants were aged 6–11 years (38.5% 

Descriptive statistics for 2009–

received HUD housing assistance during 

compared to 32.9%) and non-Hispanic 

2012 NHANES adult participants and 

the 1999–2014 HUD administrative 

black (47.7% compared to 15.3%), and 

linked adult survey participants aged 

period, including those receiving HUD 

had family incomes that were below the 

18 and over are presented in Table 7. 

housing assistance at the time of their 

poverty threshold (59.2% compared to 

The distributions of sex, age, race and 

survey interview and/or examination. 

21.5%). The percentage of children with 

ethnicity, poverty status, health status, 

While the distribution of various 

fair or poor health was higher among the 

and health insurance coverage differed 

characteristics (such as sex, or race and 

linked child survey participants (5.0%) 

between the two populations. Compared 

ethnicity) remained consistent between 

than among NHIS child participants 

to NHANES adult participants, more 

individuals who had been linked and the 

(1.9%), and more linked child survey 

linked adult survey participants were 

overall sample, several characteristics 

participants had public insurance (67.7%)  female (66.7% compared to 51.7%), aged  appear to differ (such as poverty status). 

compared to NHIS child participants 

18–39 (52.8% compared to 38.7%), and 

These differences in characteristics, as 

(26.6%).

non-Hispanic black (35.6% compared 

well as changes in the data or receipt of 

Descriptive statistics for 2008–2012 

to 11.6%), and had family incomes that 

assistance over time, may impact findings 

NHIS adult participants and linked adult 

were below the poverty guideline (47.1%  from analyses of the linked NCHS–HUD 

survey participants are presented in Table 5.  compared to 15.8%), had fair or poor data. 

The distributions of sex, age, race and 

health (33.5% compared to 17.2%), and 

The linkage of health data from 

ethnicity, poverty status, health status, 

were uninsured (26.1% compared to 

NHIS and NHANES to housing 

and health insurance coverage among 

20.3%).

assistance data from the HUD 

linked adult survey participants differed 

These results may assist researchers 

administrative records enhances the 

between the two populations. Compared 

in understanding how linked survey 

utility of these population health surveys 

to NHIS adult participants, more linked 

participants differ from the overall 

as well as the HUD administrative data. 

adult survey participants were female 

survey sample and demonstrate that 

The NCHS–HUD linkage provides 

(69.5% compared to 51.7%), aged 

inferences about research findings 

a unique opportunity to examine the 

18–39 (54.9% compared to 39.1%), and 

based on the linked sample may not be 

relationship between receipt of assisted 

non-Hispanic black (37.1% compared 

generalizable to the national population. 

housing and various health-related 

to 11.9%), and had family incomes that 

Additionally, the linked data are not 

outcomes, such as access to health care 

were below the poverty threshold (48.0%  intended to reflect the entire population and utilization of health services, general 

compared to 12.8%), fair or poor health 

of HUD housing assistance recipients. 

health status, health characteristics, and 

(29.1% compared to 12.7%), and public 

The linked participants represent 

health behaviors.

insurance (47.7% compared to 15.3%).

the survey participants that received 

Descriptive statistics for 2009–2012 

federal housing assistance at some 

NHANES child participants and linked 

time point in the linked NCHS–HUD 

child survey participants are presented 

administrative period. This may not 

in Table 6. The percentages of linked 

be the same as the entire population 

Page 10   Series 1, No. 60

Published Research 

National Center for Health Statistics.  16.  RTI International. SUDAAN 

Papers Using NCHS 

Vital Health Stat 2(161). 2013.

language manual, vol 1–2  

6.  National Center for Health Statistics. 

(Release 11). 2012.

Surveys Linked to 

National Health and Nutrition 

17.  Johnson CL, Paulose-Ram R, 

Examination Survey: Analytic 

Ogden CL, et al. National Health 

HUD Data

guidelines, 2011–2012. Hyattsville, 

and Nutrition Examination Survey: 

MD. 2013.

Analytic guidelines, 1999–2010. 

7.  Lloyd PC, Helms VE. NCHS–HUD 

National Center for Health Statistics. 

● Ahrens KA, Haley BA, Rossen 

linked data: Analytic considerations 

Vital Health Stat 2(161). 2013.

LM, Lloyd PC, Aoki Y. Housing 

and guidelines. Hyattsville, MD: 

18.  National Center for Health Statistics. 

assistance and blood lead levels: 

National Center for Health Statistics. 

Variance estimation guidance, NHIS 

Children in the United States, 

2016. Available from: https:/ www.

2006–2015. Hyattsville, MD. 2016.

2005–2012. Am J Public Health 

cdc.gov/nchs/data/datalinkage/nchs_

19.  National Center for Health Statistics. 

106(11):2049–56. 2016. 

hud_analytic_considerations.pdf.

Variance estimation and other 

● Fenelon A, Mayne P, Simon AE, 

8.  Miller DM, Gindi RM, Parker JD. 

analytic issues in the 1997–2005 

Rossen LM, Helms V, Lloyd P, et al. 

Trends in record linkage refusal 

NHIS. Hyattsville, MD. 2009.

Housing assistance programs and 

rates: Characteristics of National 

adult health in the United States. Am 

Health Interview Survey participants 

J Public Health 107(4):571–8. 2017.

who refuse record linkage. Presented 

● Helms VE, King BA, Ashley PJ. 

at: Joint Statistical Meeting. Miami 

Cigarette smoking and adverse health 

Beach, FL: American Statistical 

outcomes among adults receiving 

Association. 2011.

federal housing assistance. Prev Med  9.  Sayer B, Cox C. How many digits 

99:171–7. 2017.

in a handshake? The role of SSN 

● Simon AE, Fenelon A, Helms E, 

in NDI record linkage. Presented 

Lloyd PC, Rossen LM. HUD housing 

at: Joint Statistical Meeting. San 

assistance associated with lower 

Francisco, CA: American Statistical 

uninsurance rates and unmet medical 

Association. 2003. 

need. Health Aff 36(6):1016–23. 2017. 10.  Black PE. Dictionary of algorithms and data structures. 2009. Available 

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NCHS–HUD linked data: Data 

1.  National Center for Health Statistics. 

dictionary. 2016.

National Health Interview Survey. 

12.  Botman SL, Moriarity CL. Design 

NCHS Fact Sheet. 2016. 

and estimation for the National 

2.  Parsons VL, Moriarity C, Jonas K, 

Health Interview Survey, 1995–

et al. Design and estimation for the 

2004. National Center for Health 

National Health Interview Survey, 

Statistics. Vital Health Stat 2(130). 

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Health Statistics. Vital Health Stat 

13.  Curtin LR, Mohadjer LK, 

2(165). 2014.

Dohrmann SM, et al. The National 

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Health and Nutrition Examination 

National Health and Nutrition 

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Examination Survey. NCHS Fact 

National Center for Health Statistics. 

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Vital Health Stat 2(155). 2012.

4.  Zipf G, Chiappa M, Porter KS, et 

14.  Curtin LR, Mohadjer LK, 

al. National Health and Nutrition 

Dohrmann SM, et al. National 

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Health and Nutrition Examination 

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National Center for Health Statistics. 

Health Stat 1(56). 2013.

Vital Health Stat 2(160). 2013.

5.  Johnson CL, Paulose-Ram R, 

15.  Judson DH, Parker JD, Larsen 

Ogden CL, et al. National Health 

MD. Adjusting sample weights for 

and Nutrition Examination Survey: 

linkage-eligibility using SUDAAN. 

Analytic guidelines, 1999–2010. 

Hyattsville, MD: National Center for 

Health Statistics. 2013.

Table 1. Sample size and percentage of survey participants linked to HUD data, by survey year and age at interview: National Health Interview Survey, 1999–2012

 All NHIS participants 

Sample Adult

Sample Child

 Eligible for linkage 

 Linked to HUD 

Eligible for linkage

Linked to HUD

Eligible for linkage

Linked to HUD

Survey year and  

age (years) at  

 Total 

Percent of  

Percent of 

 Total  

Percent of  

Percent of  

 Total  

Percent of 

Percent of  

NHIS interview

sample 

  n 

total

   n 

eligible

sample 

  n 

total

  n 

eligible

sample 

  n 

total

  n 

eligible

1999–2012

Total  . . . . . . . . . . . . . . . . . . .   1,291,224   316,102 

24.48

 27,555 

8.72

 413,027 

 205,905 

49.85

 18,610 

9.04

 166,212 

 41,599 

25.03

 4,939 

11.87

1999

Total  . . . . . . . . . . . . . . . . . . . 

 97,059 

 36,822 

37.94

 2,673 

7.26

 30,801 

 17,115 

 55.57 

 1,411 

8.24

 12,910 

 3,698 

 28.64 

 344 

9.30

0–17  . . . . . . . . . . . . . . . . . 

 27,271 

 7,050 

25.85

 698 

9.90

 ... 

 ... 

 ... 

 ... 

...

 12,910 

 3,698 

 28.64 

 344 

9.30

18–39  . . . . . . . . . . . . . . . . 

 30,183 

 11,709 

38.79

 905 

7.73

 12,544 

 6,716 

 53.54 

 603 

8.98

 ... 

 ... 

 ... 

 ... 

...

40–64  . . . . . . . . . . . . . . . . 

 28,605 

 12,387 

43.30

 671 

5.42

 12,255 

 6,750 

 55.08 

 465 

6.89

 ... 

 ... 

 ... 

 ... 

...

65 and over . . . . . . . . . . . . 

 11,000 

 5,676 

51.60

 399 

7.03

 6,002 

 3,649 

 60.80

 343 

9.40

 ... 

 ... 

 ... 

 ... 

...

2000

Total  . . . . . . . . . . . . . . . . . . . 

 100,618 

 35,318 

35.10

 2,815 

7.97

 32,374 

 16,605 

 51.29 

 1,433 

8.63

 13,376 

 3,504 

 26.2 

 393 

11.22

0–17  . . . . . . . . . . . . . . . . . 

 28,495 

 6,755 

23.71

 829 

12.27

 ... 

 ... 

 ... 

 ... 

...

 13,376 

 3,504 

 26.2 

 393 

11.22

18–39  . . . . . . . . . . . . . . . . 

 31,153 

 11,263 

36.15

 892 

7.92

 13,283 

 6,512 

 49.03 

 609 

9.35

 ... 

 ... 

 ... 

 ... 

...

40–64  . . . . . . . . . . . . . . . . 

 29,764 

 11,903 

39.99

 680 

5.71

 12,911 

 6,609 

 51.19 

 479 

7.25

 ... 

 ... 

 ... 

 ... 

...

65 and over . . . . . . . . . . . . 

 11,206 

 5,397 

48.16

 414 

7.67

 6,180 

 3,484 

 56.38 

 345 

9.90

 ... 

 ... 

 ... 

 ... 

...

2001

Total  . . . . . . . . . . . . . . . . . . . 

 100,760 

 35,397 

35.13

 2,701 

7.63

 33,326 

 16,997 

 51.00

 1,384 

8.14

 13,579 

 3,551 

 26.15 

 406 

11.43

0–17  . . . . . . . . . . . . . . . . . 

 28,572 

 6,763 

23.67

 807 

11.93

 ... 

 ... 

 ... 

 ... 

...

 13,579 

 3,551 

 26.15 

 406 

11.43

18–39  . . . . . . . . . . . . . . . . 

 30,941 

 11,131 

35.97

 912 

8.19

 13,555 

 6,590 

 48.62 

 612 

9.29

 ... 

 ... 

 ... 

 ... 

...

40–64  . . . . . . . . . . . . . . . . 

 30,230 

 12,191 

40.33

 612 

5.02

 13,619 

 6,939 

 50.95 

 461 

6.64

 ... 

 ... 

 ... 

 ... 

...

65 and over . . . . . . . . . . . . 

 11,017 

 5,312 

48.22

 370 

6.97

 6,152 

 3,468 

 56.37 

 311 

8.97

 ... 

 ... 

 ... 

 ... 

...

2002

Total  . . . . . . . . . . . . . . . . . . . 

 93,386 

 16,681 

17.86

 1,385 

8.30

 31,044 

 11,353 

 36.57 

 1,119 

9.86

 12,524 

 ... 

 ... 

 ... 

 ... 

0–17  . . . . . . . . . . . . . . . . . 

 26,191 

 ... 

 ... 

 ... 

 ... 

 ... 

 ... 

 ... 

 ... 

 ... 

 12,524 

 ... 

 ... 

 ... 

 ... 

18–39  . . . . . . . . . . . . . . . . 

 28,298 

 6,148 

21.73

 600 

9.76

 12,467 

 4,219 

 33.84 

 455 

10.78

 ... 

 ... 

 ... 

 ... 

...

40–64  . . . . . . . . . . . . . . . . 

 28,312 

 7,134 

25.20

 472 

6.62

 12,717 

 4,629 

 36.40 

 373 

8.06

 ... 

 ... 

 ... 

 ... 

...

65 and over . . . . . . . . . . . . 

 10,585 

 3,399 

32.11

 313 

9.21

 5,860 

 2,505 

 42.75 

 291 

11.62

 ... 

 ... 

 ... 

 ... 

...

2003

Total  . . . . . . . . . . . . . . . . . . . 

 92,148 

 14,805 

16.07

 1,305 

8.81

 30,852 

 10,223 

 33.14 

 1,062 

10.39

 12,249 

 ... 

 ... 

 ... 

 ... 

0–17  . . . . . . . . . . . . . . . . . 

 25,537 

 ... 

 ... 

 ... 

 ... 

 ... 

 ... 

 ... 

 ... 

...

 12,249 

 ... 

 ... 

 ... 

 ... 

18–39  . . . . . . . . . . . . . . . . 

 27,809 

 5,383 

19.36

 568 

10.55

 12,154 

 3,782 

 31.12 

 446 

11.79

 ... 

 ... 

 ... 

 ... 

...

40–64  . . . . . . . . . . . . . . . . 

 28,529 

 6,416 

22.49

 474 

7.39

 12,939 

 4,204 

 32.49 

 384 

9.13

 ... 

 ... 

 ... 

 ... 

...

65 and over . . . . . . . . . . . . 

 10,273 

 3,006 

29.26

 263 

8.75

 5,759 

 2,237 

 38.84 

 232 

10.37

 ... 

 ... 

 ... 

 ... 

...

2004

Ser

Total  . . . . . . . . . . . . . . . . . . . 

 94,460 

 21,744 

23.02

 1,790 

8.23

 31,326 

 13,428 

 42.87 

 1,170 

8.71

 12,424 

 3,170 

 25.52 

 384 

12.11

0–17  . . . . . . . . . . . . . . . . . 

 26,161 

 3,175 

12.14

 384 

12.09

 ... 

 ... 

 ... 

 ... 

...

 12,424 

 3,170 

 25.52 

 384 

12.11

ies 1, No

18–39  . . . . . . . . . . . . . . . . 

 28,015 

 6,896 

24.62

 648 

9.40

 12,052 

 5,080 

 42.15 

 517 

10.18

 ... 

 ... 

 ... 

 ... 

...

40–64  . . . . . . . . . . . . . . . . 

 29,526 

 7,984 

27.04

 463 

5.80

 13,255 

 5,503 

 41.52 

 384 

6.98

 ... 

 ... 

 ... 

 ... 

...

65 and over . . . . . . . . . . . . 

 10,758 

 3,689 

34.29

 295 

8.00

 6,019 

 2,845 

 47.27 

 269 

9.46

 ... 

 ... 

 ... 

 ... 

...

. 60

  

Page 1

1 

See footnotes at end of table.

Page 1

Table 1. Sample size and percentage of survey participants linked to HUD data, by survey year and age at interview: National Health Interview Survey, 1999–2012—Con.

2

 All NHIS participants 

Sample Adult

Sample Child

  

 Eligible for linkage 

 Linked to HUD 

Eligible for linkage

Linked to HUD

Eligible for linkage

Linked to HUD

Ser

Survey year and  

ies 1, No

age (years) at  

 Total 

Percent of  

Percent of 

 Total  

Percent of  

Percent of  

 Total  

Percent of 

Percent of  

NHIS interview

sample 

  n 

total

   n 

eligible

sample 

  n 

total

  n 

eligible

sample 

  n 

total

  n 

eligible

2005

. 60

Total  . . . . . . . . . . . . . . . . . . . 

 98,649 

 18,765 

19.02

 1,608 

8.57

 31,428 

 11,727 

 37.31 

 1,036 

8.83

 12,523 

 2,658 

 21.22 

 331 

12.45

0–17  . . . . . . . . . . . . . . . . . 

 26,814 

 2,660 

9.92

 332 

12.48

 ... 

 ... 

 ... 

 ... 

...

 12,523 

 2,658 

 21.22 

 331 

12.45

18–39  . . . . . . . . . . . . . . . . 

 28,982 

 5,778 

19.94

 619 

10.71

 11,810 

 4,260 

 36.07 

 488 

11.46

 ... 

 ... 

 ... 

 ... 

...

40–64  . . . . . . . . . . . . . . . . 

 31,623 

 7,137 

22.57

 442 

6.19

 13,540 

 4,959 

 36.62 

 351 

7.08

 ... 

 ... 

 ... 

 ... 

...

65 and over   . . . . . . . . . . . 

 11,230 

 3,190 

28.41

 215 

6.74

 6,078 

 2,508 

 41.26 

 197 

7.85

 ... 

 ... 

 ... 

 ... 

...

2006

Total  . . . . . . . . . . . . . . . . . . . 

 75,716 

 13,319 

17.59

 1,370 

10.29

 24,275 

 8,418 

 34.68 

 919 

10.92

 9,837 

 1,806 

 18.36 

 249 

13.79

0–17  . . . . . . . . . . . . . . . . . 

 20,903 

 1,806 

8.64

 249 

13.79

 ... 

 ... 

 ... 

 ... 

...

 9,837 

 1,806 

 18.36 

 249 

13.79

18–39  . . . . . . . . . . . . . . . . 

 22,578 

 4,322 

19.14

 535 

12.38

 9,418 

 3,235 

 34.35 

 440 

13.60

 ... 

 ... 

 ... 

 ... 

...

40–64  . . . . . . . . . . . . . . . . 

 23,845 

 4,922 

20.64

 387 

7.86

 10,210 

 3,401 

 33.31 

 300 

8.82

 ... 

 ... 

 ... 

 ... 

...

65 and over   . . . . . . . . . . . 

 8,390 

 2,269 

27.04

 199 

8.77

 4,647 

 1,782 

 38.35 

 179 

10.04

 ... 

 ... 

 ... 

 ... 

...

2007

Total  . . . . . . . . . . . . . . . . . . . 

 75,764 

 14,247 

18.8

 1,338 

9.39

 23,393 

 11,643 

 49.77 

 1,012 

8.69

 9,417 

 2,604 

 27.65 

 326 

12.52

0–17  . . . . . . . . . . . . . . . . . 

 20,719 

 2,604 

12.57

 326 

12.52

 ... 

 ... 

 ... 

 ... 

...

 9,417 

 2,604 

 27.65 

 326 

12.52

18–39  . . . . . . . . . . . . . . . . 

 22,598 

 4,358 

19.28

 484 

11.11

 8,864 

 4,358 

 49.17 

 484 

11.11

 ... 

 ... 

 ... 

 ... 

...

40–64  . . . . . . . . . . . . . . . . 

 24,008 

 5,029 

20.95

 349 

6.94

 9,946 

 5,029 

 50.56 

 349 

6.94

 ... 

 ... 

 ... 

 ... 

...

65 and over   . . . . . . . . . . . 

 8,439 

 2,256 

26.73

 179 

7.93

 4,583 

 2,256 

 49.23 

 179 

7.93

 ... 

 ... 

 ... 

 ... 

...

2008

Total  . . . . . . . . . . . . . . . . . . . 

 74,236 

 15,268 

20.57

 1,462 

9.58

 21,781 

 12,438 

 57.10

 1,109 

8.92

 8,815 

 2,830 

 32.1 

 353 

12.47

0–17  . . . . . . . . . . . . . . . . . 

 19,914 

 2,830 

14.21

 353 

12.47

 ... 

 ... 

 ... 

 ... 

...

 8,815 

 2,830 

 32.1 

 353 

12.47

18–39  . . . . . . . . . . . . . . . . 

 22,116 

 4,574 

20.68

 538 

11.76

 8,067 

 4,574 

 56.70

 538 

11.76

 ... 

 ... 

 ... 

 ... 

...

40–64  . . . . . . . . . . . . . . . . 

 23,728 

 5,380 

22.67

 374 

6.95

 9,270 

 5,380 

 58.04 

 374 

6.95

 ... 

 ... 

 ... 

 ... 

...

65 and over   . . . . . . . . . . . 

 8,478 

 2,484 

29.3

 197 

7.93

 4,444 

 2,484 

 55.90 

 197 

7.93

 ... 

 ... 

 ... 

 ... 

...

2009

Total  . . . . . . . . . . . . . . . . . . . 

 88,446 

 21,580 

24.4

 2,208 

10.23

 27,731 

 17,413 

 62.79 

 1,653 

9.49

 11,156 

 4,167 

 37.35 

 555 

13.32

0–17  . . . . . . . . . . . . . . . . . 

 23,830 

 4,167 

17.49

 555 

13.32

 ... 

 ... 

 ... 

 ... 

...

 11,156 

 4,167 

 37.35 

 555 

13.32

18–39  . . . . . . . . . . . . . . . . 

 25,952 

 6,306 

24.3

 794 

12.59

 10,277 

 6,306 

 61.36 

 794 

12.59

 ... 

 ... 

 ... 

 ... 

...

40–64  . . . . . . . . . . . . . . . . 

 28,546 

 7,608 

26.65

 592 

7.78

 11,961 

 7,608 

 63.61 

 592 

7.78

 ... 

 ... 

 ... 

 ... 

...

65 and over   . . . . . . . . . . . 

 10,118 

 3,499 

34.58

 267 

7.63

 5,493 

 3,499 

 63.70

 267 

7.63

 ... 

 ... 

 ... 

 ... 

...

2010

Total  . . . . . . . . . . . . . . . . . . . 

 89,976 

 20,139 

22.38

 1,917 

9.52

 27,157 

 16,073 

 59.19 

 1,447 

9.00

 11,277 

 4,066 

 36.06 

 470 

11.56

0–17  . . . . . . . . . . . . . . . . . 

 24,057 

 4,066 

16.9

 470 

11.56

 ... 

 ... 

 ... 

 ... 

...

 11,277 

 4,066 

 36.06 

 470 

11.56

18–39  . . . . . . . . . . . . . . . . 

 26,788 

 5,970 

22.29

 684 

11.46

 10,200 

 5,970 

 58.53 

 684 

11.46

 ... 

 ... 

 ... 

 ... 

...

40–64  . . . . . . . . . . . . . . . . 

 28,691 

 6,912 

24.09

 515 

7.45

 11,507 

 6,912 

 60.07 

 515 

7.45

 ... 

 ... 

 ... 

 ... 

...

65 and over . . . . . . . . . . . .   

 10,440 

 3,191 

30.57

 248 

7.77

 5,450 

 3,191 

 58.55 

 248 

7.77

 ... 

 ... 

 ... 

 ... 

...

See footnotes at end of table.

Table 1. Sample size and percentage of survey participants linked to HUD data, by survey year and age at interview: National Health Interview Survey, 1999–2012—Con.

 All NHIS participants 

Sample Adult

Sample Child

 Eligible for linkage 

 Linked to HUD 

Eligible for linkage

Linked to HUD

Eligible for linkage

Linked to HUD

Survey year and  

age (years) at  

 Total 

Percent of  

Percent of 

 Total  

Percent of  

Percent of  

 Total  

Percent of 

Percent of  

NHIS interview

sample 

  n 

total

   n 

eligible

sample 

  n 

total

  n 

eligible

sample 

  n 

total

  n 

eligible

2011

Total  . . . . . . . . . . . . . . . . . . . 

 101,875 

 25,786 

25.31

 2,378 

9.22

 33,014 

 21,055 

 63.78 

 1,820 

8.64

 12,850 

 4,731 

 36.82 

 558 

11.79

0–17  . . . . . . . . . . . . . . . . . 

 26,802 

 4,731 

17.65

 558 

11.79

 ... 

 ... 

 ... 

 ... 

...

 12,850 

 4,731 

 36.82 

 558 

11.79

18–39  . . . . . . . . . . . . . . . . 

 29,970 

 7,704 

25.71

 901 

11.70

 12,191 

 7,704 

 63.19 

 901 

11.70

 ... 

 ... 

 ... 

 ... 

...

40–64  . . . . . . . . . . . . . . . . 

 32,586 

 8,870 

27.22

 608 

6.85

 13,921 

 8,870 

 63.72 

 608 

6.85

 ... 

 ... 

 ... 

 ... 

...

65 and over   . . . . . . . . . . . 

 12,517 

 4,481 

35.80

 311 

6.94

 6,902 

 4,481 

 64.92 

 311 

6.94

 ... 

 ... 

 ... 

 ... 

...

2012

Total  . . . . . . . . . . . . . . . . . . . 

 108,131 

 26,231 

24.26

 2,605 

9.93

 34,525 

 21,417 

 62.03 

 2,035 

9.50

 13,275 

 4,814 

 36.26 

 570 

11.84

0–17  . . . . . . . . . . . . . . . . . 

 28,016 

 4,814 

17.18

 570 

11.84

 ... 

 ... 

 ... 

 ... 

...

 13,275 

 4,814 

 36.26 

 570 

11.84

18–39  . . . . . . . . . . . . . . . . 

 31,184 

 7,555 

24.23

 972 

12.87

 12,434 

 7,555 

 60.76 

 972 

12.87

 ... 

 ... 

 ... 

 ... 

...

40–64  . . . . . . . . . . . . . . . . 

 35,361 

 9,218 

26.07

 700 

7.59

 14,709 

 9,218 

 62.67 

 700 

7.59

 ... 

 ... 

 ... 

 ... 

...

65 and over . . . . . . . . . . . .   

 13,570 

 4,644 

34.22

 363 

7.82

 7,382 

 4,644 

 62.91 

 363 

7.82

 ... 

 ... 

 ... 

 ... 

...

... Category not applicable.

NOTE: HUD is U.S. Department of Housing and Urban Development, and NHIS is National Health Interview Survey.

SOURCES: NCHS, 1999–2012 NHIS data linked to 1999–2014 HUD administrative records.

Ser

ies 1, No

. 60

  

Page 1

3 

Page 14   Series 1, No. 60

Table 2. Sample size and percentage of survey participants linked to HUD data, by survey year and age at interview: National Health and Nutrition Examination Survey, 1999–2012

All NHANES participants

MEC participants

Eligible for linkage

Linked to HUD

Eligible for linkage

Linked to HUD

Survey year and  

age (years) at 

 Total 

Percent of 

Percent of 

 Total 

Percent of 

Percent of 

NHANES interview

sample 

  n 

total

  n 

eligible

sample 

  n 

total

  n 

eligible

1999–2012

Total  . . . . . . . . . . . . . . . . . . . . . . .  71,916 

 50,559 

70.30

 6,532 

12.92

75,127

 48,769 

 64.92 

 6,354 

13.03

1999–2000

Total  . . . . . . . . . . . . . . . . . . . . . . .

 9,965 

 7,235 

72.60

 882 

12.19

10,648

 6,843 

 64.27 

 850 

12.42

0–17  . . . . . . . . . . . . . . . . . . . . .

 4,517 

 2,933 

64.93

 452 

15.41

4,728

 2,839 

 60.05 

 443 

15.60

18–39  . . . . . . . . . . . . . . . . . . . .

 2,263 

 1,714 

75.74

 188 

10.97

2,425

 1,607 

 66.27 

 183 

11.39

40–64  . . . . . . . . . . . . . . . . . . . .

 1,793 

 1,475 

82.26

 127 

8.61

1,907

 1,400 

 73.41 

 122 

8.71

65 and over . . . . . . . . . . . . . . . .

 1,392 

 1,113 

79.96

 115 

10.33

1,588

 997 

 62.78 

 102 

10.23

2001–2002

Total  . . . . . . . . . . . . . . . . . . . . . . .  11,039 

 8,715 

78.95

 1,199 

13.76

11,601

 8,346 

 71.94 

 1,160 

13.90

0–17  . . . . . . . . . . . . . . . . . . . . .

 5,046 

 3,709 

73.50

 711 

19.17

5,207

 3,626 

 69.64 

 700 

19.31

18–39  . . . . . . . . . . . . . . . . . . . .

 2,507 

 2,002 

79.86

 266 

13.29

2,606

 1,929 

 74.02 

 261 

13.53

40–64  . . . . . . . . . . . . . . . . . . . .

 2,023 

 1,753 

86.65

 108 

6.16

2,104

 1,691 

 80.37 

 104 

6.15

65 and over . . . . . . . . . . . . . . . .

 1,463 

 1,251 

85.51

 114 

9.11

1,684

 1,100 

 65.32 

 95 

8.64

2003–2004

Total  . . . . . . . . . . . . . . . . . . . . . . .  10,122 

 8,084 

79.87

 1,075 

13.30

10,601

 7,764 

 73.24 

 1,045 

13.46

0–17  . . . . . . . . . . . . . . . . . . . . .

 4,502 

 3,265 

72.52

 600 

18.38

4,664

 3,176 

 68.10

 587 

18.48

18–39  . . . . . . . . . . . . . . . . . . . .

 2,321 

 1,930 

83.15

 258 

13.37

2,425

 1,856 

 76.54 

 255 

13.74

40–64  . . . . . . . . . . . . . . . . . . . .

 1,805 

 1,573 

87.15

 126 

8.01

1,896

 1,501 

 79.17 

 123 

8.19

65 and over . . . . . . . . . . . . . . . .

 1,494 

 1,316 

88.09

 91 

6.91

1,616

 1,231 

 76.18 

 80 

6.50

2005–2006

Total  . . . . . . . . . . . . . . . . . . . . . . .  10,348 

 7,298 

70.53

 911 

12.48

10,746

 7,073 

 65.82 

 888 

12.55

0–17  . . . . . . . . . . . . . . . . . . . . .

 4,785 

 3,079 

64.35

 522 

16.95

4,954

 3,001 

 60.58 

 510 

16.99

18–39  . . . . . . . . . . . . . . . . . . . .

 2,507 

 1,816 

72.44

 211 

11.62

2,614

 1,748 

 66.87 

 205 

11.73

40–64  . . . . . . . . . . . . . . . . . . . .

 1,867 

 1,448 

77.56

 111 

7.67

1,925

 1,413 

 73.40

 109 

7.71

65 and over . . . . . . . . . . . . . . . .

 1,189 

 955 

80.32

 67 

7.02

1,253

 911 

 72.71 

 64 

7.03

2007–2008

Total  . . . . . . . . . . . . . . . . . . . . . . .  10,149 

 6,724 

66.25

 873 

12.98

10,536

 6,543 

 62.10

 858 

13.11

0–17  . . . . . . . . . . . . . . . . . . . . .

 3,921 

 2,186 

55.75

 427 

19.53

4,075

 2,127 

 52.20 

 417 

19.61

18–39  . . . . . . . . . . . . . . . . . . . .

 2,203 

 1,537 

69.77

 217 

14.12

2,274

 1,501 

 66.01 

 215 

14.32

40–64  . . . . . . . . . . . . . . . . . . . .

 2,469 

 1,823 

73.84

 157 

8.61

2,543

 1,784 

 70.15 

 156 

8.74

65 and over . . . . . . . . . . . . . . . .

 1,556 

 1,178 

75.71

 72 

6.11

1,644

 1,131 

 68.80 

 70 

6.19

2009–2010

Total  . . . . . . . . . . . . . . . . . . . . . . .  10,537 

 6,607 

62.70

 754 

11.41

10,821

 6,482 

 59.90 

 738 

11.39

0–17  . . . . . . . . . . . . . . . . . . . . .

 4,010 

 2,084 

51.97

 299 

14.35

4,127

 2,041 

 49.45 

 293 

14.36

18–39  . . . . . . . . . . . . . . . . . . . .

 2,392 

 1,587 

66.35

 219 

13.80

2,450

 1,560 

 63.67 

 217 

13.91

40–64  . . . . . . . . . . . . . . . . . . . .

 2,612 

 1,808 

69.22

 153 

8.46

2,658

 1,783 

 67.08 

 149 

8.36

65 and over . . . . . . . . . . . . . . . .

 1,523 

 1,128 

74.06

 83 

7.36

1,586

 1,098 

 69.23 

 79 

7.19

2011–2012

Total  . . . . . . . . . . . . . . . . . . . . . . .

 9,756 

 5,896 

60.43

 838 

14.21

10,174

 5,718 

 56.20 

 815 

14.25

0–17  . . . . . . . . . . . . . . . . . . . . .

 3,892 

 1,904 

48.92

 339 

17.80

4,061

 1,849 

 45.53 

 332 

17.96

18–39  . . . . . . . . . . . . . . . . . . . .

 2,261 

 1,468 

64.93

 229 

15.60

2,348

 1,420 

 60.48 

 222 

15.63

40–64  . . . . . . . . . . . . . . . . . . . .

 2,353 

 1,601 

68.04

 158 

9.87

2,431

 1,568 

 64.50 

 156 

9.95

65 and over . . . . . . . . . . . . . . . .

 1,250 

 923 

73.84

 112 

12.13

1,334

 881 

 66.04 

 105 

11.92

NOTE: HUD is U.S. Department of Housing and Urban Development, NHANES is National Health and Nutrition Examination Survey, and MEC is mobile examination center.

SOURCES: NCHS, 1999–2012 NHANES data linked to 1996–2014 HUD administrative records.

Series 1, No. 60   Page 15 

Table 3. Linked NCHS–HUD file sample size and percentage of linked survey participants with concurrent HUD enrollment within 1, 2, and 3 years of survey interview, by survey and age at interview

 Linked 

 Concurrently  

 Within 1 year  

 Within 2 years 

 Within 3 years 

respondents 

linked 

of interview 

of interview 

of interview 

Survey year and  

age (years) at  

Percent of 

Percent of 

Percent of 

Percent of 

NCHS interview

n 

  n

all linked

  n 

all linked

  n 

all linked

  n 

all linked

NHIS

1999–2012 total  . . . . . . . . . . . . . . . .

 27,555 

 11,060 

40.1

 16,076 

58.3

 18,666 

67.7

 20,394 

74.0

1999 total  . . . . . . . . . . . . . . . . . . . . .

 2,673 

 234 

08.8

 1,106 

41.4

 1,638 

61.3

 1,805 

67.5

0–17  . . . . . . . . . . . . . . . . . . . . . . .

 698 

 48 

06.9

 316 

45.3

 488 

69.9

 520 

74.5

18–39  . . . . . . . . . . . . . . . . . . . . . .

 905 

 56 

06.2

 327 

36.1

 507 

56.0

 584 

64.5

40–64  . . . . . . . . . . . . . . . . . . . . . .

 671 

 56 

08.4

 241 

35.9

 355 

52.9

 390 

58.1

65 and over . . . . . . . . . . . . . . . . . .

 399 

 74 

18.6

 222 

55.6

 288 

72.2

 311 

77.9

2000 total  . . . . . . . . . . . . . . . . . . . . .

 2,815 

 735 

26.1

 1,557 

55.3

 1,783 

63.3

 1,998 

71.0

0–17  . . . . . . . . . . . . . . . . . . . . . . .

 829 

 226 

27.3

 496 

59.8

 571 

68.9

 637 

76.8

18–39  . . . . . . . . . . . . . . . . . . . . . .

 892 

 192 

21.5

 455 

51.0

 540 

60.5

 621 

69.6

40–64  . . . . . . . . . . . . . . . . . . . . . .

 680 

 160 

23.5

 331 

48.7

 369 

54.3

 416 

61.2

65 and over . . . . . . . . . . . . . . . . . .

 414 

 157 

37.9

 275 

66.4

 303 

73.2

 324 

78.3

2001 total  . . . . . . . . . . . . . . . . . . . . .

 2,701 

 806 

29.8

 1,517 

56.2

 1,777 

65.8

 1,933 

71.6

0–17  . . . . . . . . . . . . . . . . . . . . . . .

 807 

 234 

29.0

 464 

57.5

 565 

70.0

 612 

75.8

18–39  . . . . . . . . . . . . . . . . . . . . . .

 912 

 229 

25.1

 478 

52.4

 565 

62.0

 622 

68.2

40–64  . . . . . . . . . . . . . . . . . . . . . .

 612 

 195 

31.9

 320 

52.3

 366 

59.8

 399 

65.2

65 and over . . . . . . . . . . . . . . . . . .

 370 

 148 

40.0

 255 

68.9

 281 

76.0

 300 

81.1

2002 total  . . . . . . . . . . . . . . . . . . . . .

 1,385 

 483 

34.9

 802 

57.9

 959 

69.2

 1,046 

75.5

0–17  . . . . . . . . . . . . . . . . . . . . . . .

 ... 

 ... 

 ... 

 ... 

 ... 

 ... 

 ... 

 ... 

 ... 

18–39  . . . . . . . . . . . . . . . . . . . . . .

 600 

 176 

29.3

 320 

53.3

 410 

68.3

 457 

76.2

40–64  . . . . . . . . . . . . . . . . . . . . . .

 472 

 167 

35.4

 277 

58.7

 317 

67.2

 343 

72.7

65 and over . . . . . . . . . . . . . . . . . .

 313 

 140 

44.7

 205 

65.5

 232 

74.1

 246 

78.6

2003 total  . . . . . . . . . . . . . . . . . . . . .

 1,305 

 537 

41.2

 800 

61.3

 929 

71.2

 1,023 

78.4

0–17  . . . . . . . . . . . . . . . . . . . . . . .

 ... 

 ... 

 ... 

 ... 

 ... 

 ... 

 ... 

 ... 

 ... 

18–39  . . . . . . . . . . . . . . . . . . . . . .

 568 

 188 

33.1

 299 

52.6

 367 

64.6

 431 

75.9

40–64  . . . . . . . . . . . . . . . . . . . . . .

 474 

 218 

46.0

 304 

64.1

 344 

72.6

 367 

77.4

65 and over . . . . . . . . . . . . . . . . . .

 263 

 131 

49.8

 197 

74.9

 218 

82.9

 225 

85.6

2004 total  . . . . . . . . . . . . . . . . . . . . .

 1,790 

 771 

43.1

 1,091 

61.0

 1,279 

71.5

 1,407 

78.6

0–17  . . . . . . . . . . . . . . . . . . . . . . .

 384 

 162 

42.2

 242 

63.0

 289 

75.3

 325 

84.6

18–39  . . . . . . . . . . . . . . . . . . . . . .

 648 

 230 

35.5

 359 

55.4

 430 

66.4

 489 

75.5

40–64  . . . . . . . . . . . . . . . . . . . . . .

 463 

 207 

44.7

 273 

59.0

 319 

68.9

 345 

74.5

65 and over . . . . . . . . . . . . . . . . . .

 295 

 172 

58.3

 217 

73.6

 241 

81.7

 248 

84.1

2005 total  . . . . . . . . . . . . . . . . . . . . .

 1,608 

 688 

42.8

 951 

59.1

 1,107 

68.8

 1,227 

76.3

0–17  . . . . . . . . . . . . . . . . . . . . . . .

 332 

 142 

42.8

 209 

63.0

 246 

74.1

 272 

81.9

18–39  . . . . . . . . . . . . . . . . . . . . . .

 619 

 229 

37.0

 331 

53.5

 394 

63.7

 446 

72.1

40–64  . . . . . . . . . . . . . . . . . . . . . .

 442 

 182 

41.2

 250 

56.6

 291 

65.8

 318 

72.0

65 and over . . . . . . . . . . . . . . . . . .

 215 

 135 

62.8

 161 

74.9

 176 

81.9

 191 

88.8

2006 total  . . . . . . . . . . . . . . . . . . . . .

 1,370 

 601 

43.9

 799 

58.3

 930 

67.9

 1,066 

77.8

0–17  . . . . . . . . . . . . . . . . . . . . . . .

 249 

 99 

39.8

 140 

56.2

 174 

69.9

 207 

83.1

18–39  . . . . . . . . . . . . . . . . . . . . . .

 535 

 197 

36.8

 283 

52.9

 327 

61.1

 383 

71.6

40–64  . . . . . . . . . . . . . . . . . . . . . .

 387 

 185 

47.8

 230 

59.4

 267 

69.0

 305 

78.8

65 and over . . . . . . . . . . . . . . . . . .

 199 

 120 

60.3

 146 

73.4

 162 

81.4

 171 

85.9

2007 total  . . . . . . . . . . . . . . . . . . . . .

 1,338 

 667 

49.9

 822 

61.4

 953 

71.2

 1,048 

78.3

0–17  . . . . . . . . . . . . . . . . . . . . . . .

 326 

 164 

50.3

 211 

64.7

 248 

76.1

 269 

82.5

18–39  . . . . . . . . . . . . . . . . . . . . . .

 484 

 215 

44.4

 270 

55.8

 323 

66.7

 357 

73.8

40–64  . . . . . . . . . . . . . . . . . . . . . .

 349 

 168 

48.1

 206 

59.0

 234 

67.1

 261 

74.8

65 and over . . . . . . . . . . . . . . . . . .

 179 

 120 

67.0

 135 

75.4

 148 

82.7

 161 

89.9

2008 total  . . . . . . . . . . . . . . . . . . . . .

 1,462 

 729 

49.9

 905 

61.9

 998 

68.3

 1,094 

74.8

0–17  . . . . . . . . . . . . . . . . . . . . . . .

 353 

 170 

48.2

 221 

62.6

 246 

69.7

 269 

76.2

18–39  . . . . . . . . . . . . . . . . . . . . . .

 538 

 212 

39.4

 279 

51.9

 320 

59.5

 370 

68.8

40–64  . . . . . . . . . . . . . . . . . . . . . .

 374 

 208 

55.6

 244 

65.2

 266 

71.1

 286 

76.5

65 and over . . . . . . . . . . . . . . . . . .

 197 

 139 

70.6

 161 

81.7

 166 

84.3

 169 

85.8

2009 total  . . . . . . . . . . . . . . . . . . . . .

 2,208 

 1,161 

52.6

 1,389 

62.9

 1,566 

70.9

 1,690 

76.5

0–17  . . . . . . . . . . . . . . . . . . . . . . .

 555 

 283 

51.0

 358 

64.5

 413 

74.4

 448 

80.7

18–39  . . . . . . . . . . . . . . . . . . . . . .

 794 

 347 

43.7

 419 

52.8

 489 

61.6

 543 

68.4

40–64  . . . . . . . . . . . . . . . . . . . . . .

 592 

 337 

56.9

 391 

66.1

 431 

72.8

 457 

77.2

65 and over . . . . . . . . . . . . . . . . . .

 267 

 194 

72.7

 221 

82.8

 233 

87.3

 242 

90.6

See footnotes at end of table.

Page 16   Series 1, No. 60

Table 3. Linked NCHS–HUD file sample size and percentage of linked survey participants with concurrent HUD enrollment within 1, 2, and 3 years of survey interview, by survey and age at interview—Con.

 Linked 

 Concurrently  

 Within 1 year  

 Within 2 years 

 Within 3 years 

respondents 

linked 

of interview 

of interview 

of interview 

Survey year and  

age (years) at  

Percent of 

Percent of 

Percent of all 

Percent of all 

NCHS interview

  n 

  n 

all linked

  n 

all linked

  n 

linked

  n 

linked

NHIS—Con.

2010 total  . . . . . . . . . . . . . . . . . . . . .

 1,917 

 974 

50.8

 1,198 

62.5

 1,337 

69.7

 1,447 

75.5

0–17  . . . . . . . . . . . . . . . . . . . . . . .

 470 

 215 

45.7

 283 

60.2

 329 

70.0

 365 

77.7

18–39  . . . . . . . . . . . . . . . . . . . . . .

 684 

 274 

40.1

 366 

53.5

 421 

61.6

 458 

67.0

40–64  . . . . . . . . . . . . . . . . . . . . . .

 515 

 294 

57.1

 343 

66.6

 370 

71.8

 395 

76.7

65 and over . . . . . . . . . . . . . . . . . .

 248 

 191 

77.0

 206 

83.1

 217 

87.5

 229 

92.3

2011 total. . . . . . . . . . . . . . . . . . . . . .

 2,378 

 1,231 

51.8

 1,481 

62.3

 1,623 

68.3

 1,731 

72.8

0–17  . . . . . . . . . . . . . . . . . . . . . . .

 558 

 266 

47.7

 351 

62.9

 394 

70.6

 423 

75.8

18–39  . . . . . . . . . . . . . . . . . . . . . .

 901 

 384 

42.6

 469 

52.1

 521 

57.8

 562 

62.4

40–64  . . . . . . . . . . . . . . . . . . . . . .

 608 

 349 

57.4

 404 

66.5

 437 

71.9

 466 

76.6

65 and over . . . . . . . . . . . . . . . . . .

 311 

 232 

74.6

 257 

82.6

 271 

87.1

 280 

90.0

2012 total  . . . . . . . . . . . . . . . . . . . . .

 2,605 

 1,443 

55.4

 1,658 

63.7

 1,787 

68.6

 1,879 

72.1

0–17  . . . . . . . . . . . . . . . . . . . . . . .

 570 

 319 

56.0

 387 

67.9

 415 

72.8

 433 

76.0

18–39  . . . . . . . . . . . . . . . . . . . . . .

 972 

 419 

43.1

 501 

51.5

 558 

57.4

 595 

61.2

40–64  . . . . . . . . . . . . . . . . . . . . . .

 700 

 415 

59.3

 455 

65.0

 486 

69.4

 519 

74.1

65 and over . . . . . . . . . . . . . . . . . .

 363 

 290 

79.9

 315 

86.8

 328 

90.4

 332 

91.5

NHANES

1999–2012 total  . . . . . . . . . . . . . . . .

 6,532 

 2,573 

39.4

 3,963 

60.7

 4,616 

70.7

 5,104 

78.1

1999–2000 total  . . . . . . . . . . . . . . . .

 882 

 202 

22.9

 498 

56.5

 608 

68.9

 654 

74.2

0–17  . . . . . . . . . . . . . . . . . . . . . . .

 452 

 101 

22.4

 266 

58.9

 326 

72.1

 349 

77.2

18–39  . . . . . . . . . . . . . . . . . . . . . .

 188 

 34 

18.1

 86 

45.7

 117 

62.2

 126 

67.0

40–64  . . . . . . . . . . . . . . . . . . . . . .

 127 

 19 

15.0

 62 

48.8

 74 

58.3

 82 

64.6

65 and over . . . . . . . . . . . . . . . . . .

 115 

 48 

41.7

 84 

73.0

 91 

79.1

 97 

84.4

2001–2002 total  . . . . . . . . . . . . . . . .

 1,199 

 343 

28.6

 702 

58.6

 848 

70.7

 935 

78.0

0–17  . . . . . . . . . . . . . . . . . . . . . . .

 711 

 219 

30.8

 452 

63.6

 534 

75.1

 587 

82.6

18–39  . . . . . . . . . . . . . . . . . . . . . .

 266 

 60 

22.6

 127 

47.7

 169 

63.5

 192 

72.2

40–64  . . . . . . . . . . . . . . . . . . . . . .

 108 

 27 

25.0

 54 

50.0

 66 

61.1

 72 

66.7

65 and over . . . . . . . . . . . . . . . . . .

 114 

 37 

32.5

 69 

60.5

 79 

69.3

 84 

73.7

2003–2004 total  . . . . . . . . . . . . . . . .

 1,075 

 475 

44.2

 683 

63.5

 789 

73.4

 883 

82.1

0–17  . . . . . . . . . . . . . . . . . . . . . . .

 600 

 275 

45.8

 408 

68.0

 467 

77.8

 523 

87.2

18–39  . . . . . . . . . . . . . . . . . . . . . .

 258 

 103 

39.9

 143 

55.4

 174 

67.4

 196 

76.0

40–64  . . . . . . . . . . . . . . . . . . . . . .

 126 

 48 

38.1

 72 

57.1

 78 

61.9

 90 

71.4

65 and over . . . . . . . . . . . . . . . . . .

 91 

 49 

53.9

 60 

65.9

 70 

76.9

 74 

81.3

2005–2006 total  . . . . . . . . . . . . . . . .

 911 

 369 

40.5

 558 

61.3

 667 

73.2

 730 

80.1

0–17  . . . . . . . . . . . . . . . . . . . . . . .

 522 

 217 

41.6

 335 

64.2

 407 

78.0

 445 

85.3

18–39  . . . . . . . . . . . . . . . . . . . . . .

 211 

 69 

32.7

 114 

54.0

 139 

65.9

 152 

72.0

40–64  . . . . . . . . . . . . . . . . . . . . . .

 111 

 50 

45.1

 64 

57.7

 70 

63.1

 78 

70.3

65 and over . . . . . . . . . . . . . . . . . .

 67 

 33 

49.3

 45 

67.2

 51 

76.1

 55 

82.1

2007–2008 total  . . . . . . . . . . . . . . . .

 873 

 402 

46.1

 518 

59.3

 590 

67.6

 664 

76.1

0–17  . . . . . . . . . . . . . . . . . . . . . . .

 427 

 207 

48.5

 273 

63.9

 306 

71.7

 341 

79.9

18–39  . . . . . . . . . . . . . . . . . . . . . .

 217 

 85 

39.2

 112 

51.6

 132 

60.8

 151 

69.6

40–64  . . . . . . . . . . . . . . . . . . . . . .

 157 

 78 

49.7

 91 

58.0

 106 

67.5

 120 

76.4

65 and over . . . . . . . . . . . . . . . . . .

 72 

 32 

44.4

 42 

58.3

 46 

63.9

 52 

72.2

2009–2010 total  . . . . . . . . . . . . . . . .

 754 

 346 

45.9

 459 

60.9

 512 

67.9

 574 

76.1

0–17  . . . . . . . . . . . . . . . . . . . . . . .

 299 

 148 

49.5

 201 

67.2

 228 

76.3

 257 

86.0

18–39  . . . . . . . . . . . . . . . . . . . . . .

 219 

 59 

26.9

 93 

42.5

 112 

51.1

 129 

58.9

40–64  . . . . . . . . . . . . . . . . . . . . . .

 153 

 79 

51.6

 97 

63.4

 103 

67.3

 116 

75.8

65 and over . . . . . . . . . . . . . . . . . .

 83 

 60 

72.3

 68 

81.9

 69 

83.1

 72 

86.8

2011–2012 total. . . . . . . . . . . . . . . . .

 838 

 436 

52.0

 545 

65.0

 602 

71.8

 664 

79.2

0–17  . . . . . . . . . . . . . . . . . . . . . . .

 339 

 182 

53.7

 234 

69.0

 260 

76.7

 290 

85.6

18–39  . . . . . . . . . . . . . . . . . . . . . .

 229 

 82 

35.8

 118 

51.5

 131 

57.2

 152 

66.4

40–64  . . . . . . . . . . . . . . . . . . . . . .

 158 

 85 

53.8

 94 

59.5

 108 

68.4

 117 

74.1

65 and over . . . . . . . . . . . . . . . . . .

 112 

 87 

77.7

 99 

88.4

 103 

92.0

 105 

93.8

… Category not applicable.

NOTE: NCHS is National Center for Health Statistics; HUD is U.S. Department of Housing and Urban Development; NHIS is National Health Interview Survey; and NHANES is National Health and Nutrition Examination Survey.

SOURCES: NCHS, 1999–2012 NHIS and NHANES data linked to 1996–2014 HUD administrative records.

Series 1, No. 60   Page 17 

Table 4. Unweighted sample size and weighted percent distribution of ever-linked 2008–2012 NHIS–HUD participants aged 0–17 years, by selected sociodemographic and health characteristics

All NHIS and HUD participants

Linked participants

Percent  

Percent  

Characteristic

n 

(weighted)

n 

(weighted)

Sex

Male  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

62,663

51.1

1,245

49.6

Female  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

59,956

48.9

1,261

50.4

Age group (years)

0–5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

40,651

34.0

712

28.8

6–11  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

40,969

32.9

883

38.5

12–17  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

40,999

33.1

911

32.7

Race and Hispanic origin

Hispanic  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

40,019

22.8

543

18.1

Non-Hispanic:

White. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

52,740

56.1

638

31.1

Black . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

21,022

15.3

1,248

47.7

Other. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

8,838

5.8

77

*3.1

Poverty level1

Below 100% of federal threshold  . . . . . . . . . . . . . . . . . . . . . . . . .

31,376

21.5

1,442

59.2

100%–200% or more of federal threshold  . . . . . . . . . . . . . . . . . .

30,639

23.1

700

27.5

200% or more of federal threshold . . . . . . . . . . . . . . . . . . . . . . . .

60,604

55.5

364

13.3

Health status2

Excellent/Very good  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

98,889

82.7

1,801

73.0

Good. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

20,975

15.3

578

22.0

Fair/Poor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2,673

1.9

127

*5.0

Health insurance

No coverage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

10,541

7.7

137

*5.3

Private insurance  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

59,576

54.8

341

14.4

Public Insurance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

38,021

26.6

1,694

67.7

Other coverage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

13,691

10.3

330

12.4

* Percentage estimate may be statistically unreliable because the absolute width of its Korn-Graubard confidence interval is between 5 and 30 percentage points, yet its relative width is larger than 130%. 

1Based on published U.S. Census Bureau poverty thresholds.

2Self-reported.

NOTES: Missing responses are not presented. NHIS is National Health Interview Survey, and HUD is U.S. Department of Housing and Urban Development.

SOURCES: NCHS, 2008–2012 NHIS data linked to 1996–2014 HUD data.

Page 18   Ser

  ies 1, No. 60

Table 5. Unweighted sample size and weighted percent distribution of ever-linked 2008–2012 NHIS–HUD participants aged 18 and over, by selected sociodemographic and health characteristics 

All NHIS and HUD 

participants

Linked participants

Percent 

Percent 

Characteristic

n

(weighted)

n 

(weighted)

Sex

Male  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

159,645

48.3

2,087

30.5

Female  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

178,897

51.7

5,977

69.5

Age group (years)

18–39  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

134,928

39.1

3,889

54.9

40–64 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

148,491

43.9

2,789

32.3

65 and over. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

55,123

17.0

1,386

12.8

Race and Hispanic origin

Hispanic  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

71,800

14.1

1,396

17.5

Non-Hispanic:

White. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

190,468

68.4

2,949

41.1

Black . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

49,091

11.9

3,377

37.1

Other. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

27,183

5.7

342

4.3

Poverty level1

Below 100% of federal threshold  . . . . . . . . . . . . . . . 

50,690

12.8

4,386

48.0

100%–200% of federal threshold  . . . . . . . . . . . . . . . 

69,661

18.8

2,356

30.5

200% of federal threshold or more . . . . . . . . . . . . . . 

218,191

68.4

1,322

21.5

Health status2

Excellent/Very good  . . . . . . . . . . . . . . . . . . . . . . . . . 

197,900

60.3

2,909

40.0

Good. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

94,218

26.8

2,562

30.8

Fair/Poor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

45,882

12.7

2,588

29.1

Health insurance

No coverage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

67,656

17.5

1,653

23.5

Private insurance  . . . . . . . . . . . . . . . . . . . . . . . . . . . 

200,361

63.2

1,681

23.0

Public insurance . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

55,963

15.3

4,255

47.7

Other coverage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

11,364

3.1

452

5.3

1Based on published U.S. Census Bureau poverty thresholds.

2Self-reported.

NOTES: Missing responses are not presented. NHIS is National Health Interview Survey, and HUD is U.S. Department of Housing and Urban Development.

SOURCES: NCHS, 2008–2012 NHIS data linked to 1996–2014 HUD data.

Series 1, No. 60   Page 19 

Table 6. Unweighted sample size and weighted percent distribution of ever-linked 2009–2012 NHANES–HUD participants aged 0–17 years, by selected sociodemographic and health characteristics

All NHANES and HUD 

participants

Linked participants

Percent 

Percent 

Characteristic

n 

weighted

n 

weighted

Sex

Male  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

4,009

50.7

336

49.1

Female  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

3,893

49.3

302

50.9

Age group (years)

0–5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

3,318

32.9

201

25.1

6–11  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

2,585

32.5

233

34.3

12–17  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

1,999

34.5

204

40.6

Race and Hispanic origin

Hispanic  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

2,354

18.9

112

16.9

Non-Hispanic:

White. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

2,389

56.0

97

26.6

Black . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

1,894

14.2

359

45.8

Other. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

1,265

10.9

70

10.6

Family income to poverty guideline ratio1

Less than 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

2,646

23.5

415

61.0

1 to 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

1,942

22.3

156

24.9

More than 2  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

2,668

47.6

50

11.1

Health status2

Excellent/Very good  . . . . . . . . . . . . . . . . . . . . . . . . . 

5,538

74.7

423

66.0

Good. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

1,925

21.0

163

26.9

Fair/Poor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

438

4.3

52

7.1

Health insurance 

Has coverage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

7,207

91.8

606

94.5

No coverage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

678

8.0

32

5.5

1Calculated using U.S. Department of Health and Human Services poverty guidelines.

2Self-reported. 

NOTES: Missing responses are not presented. NHANES is National Health and Nutrition Examination Survey, and HUD is U.S. 

Department of Housing and Urban Development.

SOURCES: NCHS, 2009–2012 NHANES data linked to 1996–2014 HUD data.

Page 20   Series 1, No. 60

Table 7. Unweighted sample size and weighted percent distribution of ever-linked 2009–2012 

NHANES–HUD participants aged 18 and over, by selected sociodemographic and health characteristics

All NHANES and HUD 

participants

Linked participants

Percent 

Percent 

Characteristic

n 

(weighted)

n 

(weighted)

Sex

Male  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

6,072

48.3

339

33.3

Female  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

6,319

51.7

615

66.7

Age group (years)

18–39  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

4,653

38.7

448

52.8

40–64 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

4,965

44.2

311

34.6

65 and over. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

2,773

17.1

195

12.6

Race and Hispanic origin

Hispanic  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

2,830

13.1

173

21.3

Non-Hispanic:

White. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

5,296

67.1

257

35.3

Black . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

2,733

11.6

446

35.6

Other. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

1,532

8.3

78

7.8

Family income to poverty guideline ratio

Less than 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

2,823

15.8

506

47.1

1 to 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

2,984

18.9

284

32.0

More than 2  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

5,394

57.9

108

15.3

Health status1

Excellent/Very good  . . . . . . . . . . . . . . . . . . . . . . . . . 

4,855

47.6

267

30.1

Good. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

4,580

35.1

334

36.4

Fair/Poor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

2,952

17.2

353

33.5

Health insurance

Has coverage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

9,326

79.6

721

73.8

No coverage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

3,047

20.3

231

26.1

1Self-reported.

NOTES: Missing responses are not presented. NHANES is National Health and Nutrition Examination Survey, and HUD is U.S. 

Department of Housing and Urban Development.

SOURCES: NCHS, 2009–2012 NHANES data linked to 1996–2014 HUD data.

Series 1, No. 60   Page 21 

Appendix I. U.S. Department of Housing and Urban Development’s 

Largest Housing Assistance Programs 

This appendix describes basic 

Multifamily Programs 

for eligible low-income residents. HUD 

characteristics of the U.S. Department 

also provides technical assistance to help 

of Housing and Urban Development’s 

The multifamily (MF) program 

PHAs plan, develop, and manage PH 

(HUD) largest housing assistance 

category in the linked NCHS–HUD 

developments. 

programs that are included in the linked 

data encompasses a number of separate, 

For PH residents, income must be 

National Center for Health Statistics 

distinct HUD programs, including: 

verified at re-examination periods every 

(NCHS) survey and HUD files. More 

Section 221(d)(3) Below Market 

12–18 months. At re-examination, if 

detailed information on these programs can  Interest Rate, Section 236 Multifamily the person’s or family’s income exceeds 

be found in the Analytic Guidelines (7).

Housing, Rental Assistance, Project-

80% of area median income, then PHA 

Based Section 8 (or PBS8) Voucher 

may reassess their eligibility for public 

Housing Choice Vouchers 

Assistance in Multifamily Housing, 

housing. In PH programs, specific 

and Related Programs 

Section 202 Supportive Housing for the 

calculations are used to determine a 

Elderly Program, Section 202/162—

tenant’s monthly rent amount. 

The Housing Choice Voucher (HCV)  Project Assistance Contract, Section 

As with tenants in an HCV program, 

program is the federal government’s 

811 Supportive Housing for Persons 

tenants participating in PH programs may 

largest housing assistance program, 

with Disabilities, and Rent Supplement. 

be served by either MTW or non-MTW 

allowing low-income families, the 

Because each of these programs lacked 

PHAs, which have different mandates 

elderly, and persons with disabilities 

sufficient sample size on an individual 

for data completeness and frequency 

to choose and lease safe and affordable 

basis in the linked file, they were 

of recertification. More information on 

housing. In the HCV program, housing 

combined into a single MF program 

the MTW demonstration project can be 

assistance is tenant-based, meaning that 

category in the linked data files.

found in the Analytic Guidelines (7).

participants find their own housing in the 

In all MF programs, subsidies are 

private market. Participants are free to 

paid directly to private property owners 

choose any housing that meets program 

who provide a certain percentage of 

requirements and are not limited to units 

their housing units at affordable rates 

located in subsidized housing projects. 

for low-income persons who qualify. 

For example, participants can choose 

Ownership may be for-profit or nonprofit. 

single-family homes, townhouses, or 

HUD subsidies (i.e., rental subsidies, 

apartments. When a public housing 

below-market interest financing, insured 

agency (PHA) issues a voucher to a 

mortgages, and other forms of assistance) 

family, the family is responsible for 

typically are linked with ongoing rental 

finding suitable housing, and the rental 

assistance for annual operating costs. 

unit owner must agree to participate in 

MF program assistance is tied to the 

the program. Selected units must meet 

property, unlike tenant-based rental 

minimal standards of health and safety 

assistance programs (e.g., HCVs), and 

as determined by the PHA. In the linked 

tenants cannot take their rental housing 

data, the HCV program also includes 

assistance subsidy elsewhere. Assistance 

Homeownership Voucher, Project-

always stays with the owner of the 

Based Voucher, Section 8 Moderate 

development during the duration of their 

Rehabilitation, and Section 8 Rental 

assistance contract. 

Certificate programs.

 The Moving to Work (MTW) 

Public Housing 

demonstration program was introduced to 

give PHAs flexibility with public housing 

The PH program was established to 

(PH) and HCV programs. Participants in 

provide safe rental housing for eligible 

HCV programs may be served by either 

low-income families, the elderly, and 

MTW or non-MTW PHAs, which have 

persons with disabilities. PH dwellings 

different mandates for data completeness 

range from scattered-site single-family 

and frequency of recertification. More 

detached houses to high-rise apartment 

information on the MTW demonstration 

buildings. HUD provides capital 

project can be found in the Analytic 

subsidies and operating subsidies to 

Guidelines (7).

local PHAs that manage public housing 

Page 22   Series 1, No. 60

Appendix II. Summary of Linked National Center for Health Statistics–

U.S. Department of Housing and Urban Development Data 

Table I. Linked NCHS–HUD data files: Name, population, and description

Data files

Universe

Description

Feasibility: 

1999–2012 NHIS–HUD

All 1999–2012 NHIS and NHANES participants

NCHS created two feasibility files for each linked survey 

file to aid researchers performing sample size and 

1999–2012 NHANES–HUD

power calculations for potential analyses. The feasibility 

files contain linkage eligibility information and program 

participation indicators for each 1999–2012 NHIS and 

NHANES participant. See Analytic Guidelines for details on 

using these files to determine sample size.

Transaction

All 1999–2012 NHIS and NHANES participants 

This file contains each transaction of the linked 1999–2012 

linked to HUD administrative data

NHIS–HUD and NHANES–HUD participants. As noted in 

Analytic Guidelines, transactions for children were removed 

if the transaction occurred after the child’s 18th birthday. 

Episode:

Episode_dates

All 1999–2012 NHIS and NHANES participants  

Seven episode files contain start and end dates for 

linked to HUD administrative data

participation in HUD programs, based on transaction data 

and assumptions about reasonable intervals between 

Episode dates–MTW HCV

Linked participants with at least one Moving to 

transactions. Because most HUD recipients must recertify 

Work Housing Choice Voucher transaction

each year, a transaction is expected each year. However, 

certain HUD program categories (e.g., Moving to Work) 

have longer intervals between recertifications. See Analytic 

Episode dates–MTW PH

Linked participants with at least one Moving to 

Guidelines for details on construction of the episode files.

Work public housing transaction

Episode dates–Other MF

Linked participants with at least one Other 

multifamily transaction

Episode dates–PBS8

Linked participants with at least one multifamily  

project-based Section 8 transaction

Episode dates–PH

Linked participants with at least one public  

housing transaction

Episode dates–HCV

Linked participants with at least one Housing  

Choice Voucher transaction

Concurrency

All 1999–2012 NHIS and NHANES participants 

This file contains variables related to the timing of HUD 

linked to HUD administrative data

housing participation relative to NCHS survey participation, 

such as indicator variables for receipt of HUD housing 

assistance at the time of survey; type of HUD housing 

assistance received; and amount of time between last 

and next transaction. See Analytic Guidelines for details 

on using concurrency variables to identify participants 

receiving HUD housing assistance at interview.

Weights

All 1999–2012 NHIS and NHANES participants

Although NHIS and NHANES are designed to be nationally 

representative of the U.S. civilian noninstitionalized 

population, not all NCHS survey participants are eligible for 

linkage. Specific weights have been calculated for analyses 

of these surveys when using linked data. One weights file 

contains a single record for all participants of 1999–2012 

NHIS and NHANES, as well as various survey weights 

adjusted for linkage eligibility.

NOTES: NHIS is National Health Interview Survey, and NHANES is National Health and Nutrition Examination Survey. HUD is U.S. Department of Housing and Urban Development, and NCHS is National Center for Health Statistics. Analytic Guidelines is available from: https://www.cdc.gov/nchs/data/datalinkage/nchs_hud_analytic_considerations.pdf. 

SOURCES: NCHS, 1999–2012 NHIS and NHANES data linked to 1996–2014 HUD data.

Series 1, No. 60   Page 23 

Appendix III. Data Variable Considerations 

The following variables may be 

Concurrency at examination 

● EXM_PH: Lived in non-MTW PH 

useful for researchers using the linked 

(NHANES only)

HUD-assisted housing at time of 

National Center for Health Statistics 

examination 

(NCHS) and U.S. Department of Housing 

● CON_STATUS_EXM: Lived in any 

●  EXM_MTW_PH: Lived in MTW 

and Urban Development (HUD) data 

type of HUD-assisted housing at 

PH HUD-assisted housing at time of 

because they provide information about 

time of examination 

examination 

whether the survey participant was linked 

● CON_STATEX_HCV: Lived in 

● EXM_PBS8: Lived in PBS8 MF 

to the HUD administrative data and 

HCV HUD-assisted housing at time 

HUD-assisted housing at time of 

the timing of receipt of HUD housing 

of examination

examination 

assistance relative to the survey interview 

● CON_STATEX_MF: Lived in MF 

● EXM_OTHER_MF: Lived in non-

and examination date:

HUD-assisted housing at time of 

PBS8 MF HUD-assisted housing at 

examination

time of examination 

● HUD_MATCH_STATUS—This 

● CON_STATEX_PH: Lived in PH 

variable can be used to identify 

HUD-assisted housing at time of 

The following 16 variables are 

participants who were eligible for 

examination 

related to the timing of HUD assistance 

linkage and who were linked to the 

relative to the survey interview or 

HUD administrative data.

examination for each HUD program 

● Concurrency variables—These 

Concurrency by 

category (HCV, MF, and PH). Although 

binary indicator variables indicate 

Subprogram (non-MTW 

these variables cannot be directly 

whether the survey participant 

HCV, MTW HCV, 

accessed by researchers, researchers can 

received HUD housing assistance at 

develop their own categorical variables 

the time of interview or examination.  non-MTW PH, MTW PH, 

based on the following:

The 20 variables are characterized 

PBS8 MF, non-PBS8 MF)

by HUD program category (Housing 

HUD Transactions 

Choice Voucher [HCV], multifamily 

Concurrency at survey interview

[MF], and public housing [PH]) and 

Occurring After Survey

● INT_HCV: Lived in non-MTW HCV 

subprogram (non-Moving to Work 

HUD-assisted housing at time of 

[MTW] HCV, MTW HCV, non-

Number of days between 

interview 

MTW PH, MTW PH, Project-Based 

interview and next HUD 

● INT_MTW_HCV: Lived in MTW–

Section [PBS] 8, and non-PBS8 

HCV HUD-assisted housing at time 

transaction

MF) at time of concurrency, and 

of interview 

●  TIME_A_INT: Number of days 

by concurrency at time of survey 

● INT_PH: Lived in non-MTW PH 

between interview and subsequent 

interview or examination (NHANES 

HUD-assisted housing at time of 

HUD transaction

only):

interview 

●  TIME_A_HCV_INT: Number 

● INT_MTW_PH: Lived in MTW–PH 

of days between interview and 

Concurrency by Program 

HUD-assisted housing at time of 

subsequent HCV transaction

(HCV, MF, PH)

interview 

●  TIME_A_MF_INT: Number of days 

● INT_PBS8: Lived in PBS8 MF 

between interview and subsequent 

Concurrency at survey interview

HUD-assisted housing at time of 

MF transaction

interview 

●  TIME_A_PH_INT: Number of days 

● CON_STATUS_INT: Lived in any 

● INT_OTHER_MF: Lived in non-

between interview and subsequent 

type of HUD-assisted housing at 

PBS8 MF HUD-assisted housing at 

PH transaction

time of interview 

time of interview 

● CON_STATIN_HCV: Lived in HCV 

HUD-assisted housing at time of 

Number of days between 

interview 

Concurrency at examination 

examination and next HUD 

● CON_STATIN_MF: Lived in MF 

(NHANES only)

transaction (NHANES only)

HUD-assisted housing at time of 

● EXM_HCV: Lived in non-MTW 

●  TIME_A_EXM: Number of days 

interview 

HCV HUD-assisted housing at time 

between examination and subsequent 

● CON_STATIN_PH: Lived in PH 

of examination 

HUD transaction

HUD-assisted housing at time of 

● EXM_MTW_HCV: Lived in MTW–

●  TIME_A_HCV_EXM: Number 

interview

HCV HUD-assisted housing at time 

of days between examination and 

of examination 

subsequent HCV transaction

Page 24   Series 1, No. 60

● TIME_A_MF_EXM: Number of 

days between examination and 

subsequent MF transaction

● TIME_A_PH_EXM: Number of 

days between examination and 

subsequent PH transaction

HUD Transactions 

Occurring Before Survey

Number of days between 

interview and previous HUD 

transaction

● TIME_B_INT: Number of days 

between interview and previous 

HUD transaction

● TIME_B_HCV_INT: Number of 

days between interview and previous 

HCV transaction

● TIME_B_MF_INT: Number of days 

between interview and previous MF 

transaction

● TIME_B_PH_INT: Number of days 

between interview and previous PH 

transaction

Number of days between 

examination and previous HUD 

transaction (NHANES only)

● TIME_B_EXM: Number of days 

between examination and previous 

HUD transaction

● TIME_B_HCV_EXM: Number 

of days between examination and 

previous HCV transaction

● TIME_B_MF_EXM: Number of 

days between examination and 

previous MF transaction

● TIME_B_PH_EXM: Number of 

days between examination and 

previous PH transaction

Series 1, No. 60   Page 25 

Appendix IV. Evaluation of NCHS–HUD Data Linkage: Comparison 

With HUD Program Recipients

This analysis assesses whether 

categories used in HUD reports or 

Because the two populations are not 

similarities or differences occur between 

publications)

statistically independent and measures of 

the linked National Center for Health 

● Indicator for households with at least  correlation between the two populations Statistics (NCHS) survey participants 

one disabled person, based on HUD’s  were not readily available, comparisons and all recipients of U.S. Department 

operational definition of disability: 

were not statistically tested.

of Housing and Urban Development 

https:/ portal.hud.gov/hudportal/

(HUD)-assisted housing. The percent 

HUD?src=/program_offices/

Evaluation of Linked 2012 

distribution of selected characteristics 

fair_housing_equal_opp/disabilities/

from all HUD housing assistance 

inhousing 

NHIS–HUD Data: Methods

recipients are presented side by side 

● Indicator for households with at least 

Recipients of HUD housing 

with that from a sample of linked 

one elderly person (HUD defines 

assistance during the 2012 calendar 

NCHS–HUD participants who received 

elderly as age 62 and over; therefore,  year were identified based on HUD 

assistance during the same time period. 

for this comparison, age 62 was 

administrative records with effective 

This evaluation uses only 1 year of 

used as the threshold to define a 

dates of Nov. 1, 2011, through Feb. 

data (2012) from the National Health 

household with an elderly person)

28, 2013. Only the most recent HUD 

Interview Survey (NHIS) and two cycles 

● Number of bedrooms in unit (0–1, 2,  transaction was retained so that each (2009–2012) of the National Health 

3, and 4 or more) 

individual was counted only once. 

and Nutrition Examination Survey 

● Total household members (1, 2, 3, 4, 

In this analysis, these HUD housing 

(NHANES). 

and 5 or more) 

assistance recipients are referred to as the 

The NCHS–HUD linked samples 

population of “all 2012 HUD-assisted 

from the 2012 NHIS and the 2009–2012 

The following criteria are used to 

tenants.” Concurrent 2012 NHIS–HUD 

NHANES are included in this analysis; 

assess similarities and differences in the 

participants are, in theory, a subset of this 

however, only variables derived from 

selected sociodemographic and household  population. Similarities and differences the HUD administrative data and not the 

characteristics between the linked survey 

between the concurrent 2012 NHIS–

NCHS survey data are described in the 

participants and all recipients of HUD-

HUD participants and all 2012 HUD-

presentations, mainly because the HUD 

assisted housing:

assisted tenants demonstrate ways in 

administrative data are the only data 

1.  If the percentage for each category 

which the linked data may or may not be 

source available for both the NCHS–

(e.g., male and female) of a 

comparable to the population of HUD 

HUD linked sample and the population 

characteristic (e.g., sex) is equal in 

housing assistance recipients. 

of HUD housing assistance recipients not 

both populations, it is described as 

The NHIS sample adult and sample 

included in the linked sample. Although 

being the same. 

child weights were used in the analyses 

some of these variables (e.g., sex, age, 

2.  If the relative difference between the  to account for unequal probabilities and total number of household members) 

two populations, defined as 

of selection and survey nonresponse, 

are also collected in the NCHS survey, 

and were further adjusted for linkage 

the mechanism for data collection differs 

| XHUDpopulation – Xlinked | / XHUDpopulation 

eligibility via poststratification by 

between administrative and survey data. 

age, race and ethnicity, and sex, using 

Analyses of these variables from the 

is between 0.0 and 0.1 for all 

SUDAAN’s procedure WTADJUST 

survey data may yield different results. 

categories of the characteristic, 

(16). Reweighting of the linked survey 

This analysis is not intended to evaluate 

concurrent linked survey 

data ensures that population totals 

the HUD administrative data, but rather 

participants are described as 

are maintained and helps account for 

to present characteristics of both the 

“consistent or similar” to all 

potential linkage consent bias. The 

NCHS–HUD linked sample and the 

recipients of HUD-assisted housing 

confidence intervals incorporate the 

population of HUD housing assistance 

with respect to that characteristic. 

complex sample design of NHIS. 

recipients. The following variables are 

3.  If the relative difference between 

included in the analysis: 

the two populations for at least 

one category of the characteristic 

Evaluation of Linked 2012 

● HUD program category—Housing 

is 0.1 or greater, concurrent linked 

NHIS–HUD Data: Results

Choice Voucher (HCV), multifamily 

survey participants are described 

(MF), and public housing (PH)

as “different (higher/more or lower/

A total of 1,434 NHIS 2012 

● Sex (male and female)

less)” than all recipients of HUD-

participants were concurrently linked 

● Age (0–17, 18–29, 30–44, 45–61, and 

assisted housing with respect to that 

to HUD administrative data. During the 

62 and over; age groups are based on 

characteristic. 

2012 time frame, the HUD administrative 

Page 26   Series 1, No. 60

records contained data on 9,790,425 

36.2% male, which was similar to the 

between the two populations. The 

HUD recipients. Results are presented in 

distribution by sex among all 2012 HUD- distribution of total household members 

Appendix Table II and Appendix Figures 

assisted tenants. The age distributions 

was similar between the two populations 

I–IV. 

were similar between the two populations  in all categories except for the 5 or more For both populations, the HCV 

for most age groups. However, the 

category; the population 

program had the highest participation 

percentage of adults aged 30–44 was 

of all 2012 HUD-assisted tenants had 

(53.7% among all 2012 HUD-assisted 

lower among all 2012 HUD-assisted 

more individuals living in households 

tenants and 49.7% among concurrent 

tenants (13.7%) than among concurrent 

with 5 or more members (20.8%) than  

2012 NHIS–HUD participants). The 

2012 NHIS–HUD participants (15.9%). 

the population of concurrent 2012  

percentage of persons in MF units among 

A higher percentage of all 2012 

NHIS–HUD participants (17.4%).

all 2012 HUD-assisted tenants was lower  HUD-assisted tenants lived in households (23.1%) than among concurrent 2012 

with a disabled person (26.2%) compared  Evaluation of Linked  

NHIS–HUD participants (29.5%), and 

to concurrent 2012 NHIS–HUD 

the percentage of all 2012 HUD-assisted 

participants (21.0%). Consistent with 

2009–2012 NHANES–HUD  

tenants in PH units was higher (23.3%) 

the population of all 2012 HUD-assisted 

Data: Methods

than among concurrent 2012 NHIS–HUD  tenants (18.6%), 18.3% of concurrent 

participants (20.8%). 

2012 NHIS–HUD participants lived in 

Two NHANES cycles were 

Concurrent 2012 NHIS–HUD 

a household with an elderly person. The 

pooled due to the small sample size of 

participants were 63.8% female and 

distribution of unit size was consistent 

concurrently linked NHANES–HUD 

Table II. Number and percent distribution of concurrently linked 2012 NHIS–HUD participants and 2012 HUD-assisted tenants, by HUD 

program and selected HUD-collected demographic characteristics

2012 HUD-assisted  

2012 concurrently linked NHIS–HUD participants 

tenants

( n = 1,434)

95% CI

Percent 

HUD program and demographic characteristics

n

Percent

n

(weighted)

Low

High

HUD housing category

Housing Choice Voucher  . . . . . . . . . . . . . . . . . . . . . . .

5,252,249

53.7

635

49.7

44.4

55.1

Multifamily housing . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2,256,365

23.1

441

29.5

23.8

35.9

Public housing  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2,281,811

23.3

358

20.8

16.3

26.1

Sex

Male  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3,665,200

37.4

460

36.2

32.5

40.0

Female  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6,124,452

62.6

973

63.8

60.0

67.5

Age group (years)

0–17  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3,931,683

40.2

318

37.2

33.9

40.6

18–29  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1,443,686

14.8

217

16.0

13.5

18.7

30–44 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1,341,524

13.7

270

15.9

13.8

18.4

45–61 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1,474,394

15.1

269

15.0

12.3

18.1

62 and over. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1,599,095

16.3

360

15.9

13.2

19.0

Households

With disabled persons  . . . . . . . . . . . . . . . . . . . . . . . . .

2,567,030

26.2

333

21.0

17.7

27.7

With elderly persons . . . . . . . . . . . . . . . . . . . . . . . . . . .

1,824,617

18.6

383

18.3

15.3

21.8

Unit size (number of bedrooms)

0–1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2,104,962

21.5

486

20.3

17.2

23.8

2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2,936,021

30.0

488

32.8

28.7

37.2

3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3,543,478

36.2

359

34.7

30.4

39.3

4 or more  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1,205,964

12.3

101

*12.2

9.1

16.3

Total household members

1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2,221,424

22.7

551

23.1

19.8

26.7

2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1,834,022

18.7

307

20.0

17.3

23.0

3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1,978,692

20.2

264

21.5

18.0

25.5

4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1,721,379

17.6

165

17.9

14.6

21.9

5 or more  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2,034,144

20.8

136

17.4

13.7

21.8

* Figure may be statistically unreliable because the absolute width of its Korn-Graubard confidence interval (CI) is between 5 and 30 percentage points, yet its relative width is larger than 130%. 

NOTES: CIs for percentages are calculated using SUDAAN with the Korn-Graubard adjustment to the Clopper-Pearson method. NHIS is National Health Interview Survey, and HUD is U.S. Department of Housing and Urban Development.

SOURCES: NCHS, linked NHIS–HUD data sample, 2012; HUD administrative data, 2012.

Series 1, No. 60   Page 27 

participants for a single cycle. Recipients 

of HUD housing assistance with effective 

80

95% CI

All 2012

2012 NHIS–HUD linked

dates from Nov. 1, 2008, through  

HUD-assisted

and concurrent

Feb. 28, 2013, were identified from the 

tenants

participants

60

HUD administrative records and included 

in the analysis to conservatively capture 

50

all HUD housing assistance recipients 

from the 2009–2012 calendar years. 

t 40

If more than one record existed per 

individual, only the most recent record 

Percen

was retained, so that each person was 

30

53.7

counted once at most. In this analysis, 

49.7

these HUD housing assistance recipients 

20

are referred to as the population of “all 

29.5

23.1

23.3

2009–2012 HUD-assisted tenants.” 

10

20.8

Concurrent 2009–2012 NHANES–HUD 

participants are, in theory, a subset of this 

0

Housing Choice

Multifamily housing

Public housing

population. Similarities and differences 

Vouchers

between the concurrent 2009–2012 

HUD housing category

NHANES–HUD participants and all 

NOTES: CI is confidence interval. HUD is U.S. Department of Housing and Urban Development; NHIS is National Health 2009–2012 HUD-assisted tenants 

Interview Survey. All variables shown are based on HUD administrative data.

SOURCES: NCHS, linked NHIS–HUD data sample, 2012; HUD administrative data, 2012. 

demonstrate ways in which the linked 

data may or may not be comparable to the 

population of HUD housing assistance 

Figure I. All 2012 HUD-assisted tenants and concurrently linked 2012 NHIS–HUD 

recipients. 

participants, by HUD housing category

The sample weights, accounting 

for unequal probabilities of selection 

and sex using SUDAAN’s WTADJUST 

and helps account for potential linkage 

and survey nonresponse, were further 

(16). Reweighting of the linked survey data  consent bias. The confidence intervals adjusted for linkage eligibility via 

ensures that population totals are maintained  reflect the complex design of NHANES. 

poststratification by age, race and ethnicity, 

80

95% CI

All 2012

2012 NHIS-HUD

HUD-assisted

linked and concurrent

tenants

participants

70

60

50

40

Percent

30

62.6

63.8

20

37.4

36.2

40.2

37.2

10

14.8

16.0

13.7

15.9

15.1 15.0

16.3

15.9

0

Male

Female

0–17

18–29

30–44

45–61

62 and over

Sex

Age group (years)

NOTES: CI is confidence interval. HUD is U.S. Department of Housing and Urban Development; NHIS is National Health Interview Survey. All variables shown are based on HUD 

administrative data.

SOURCES: NCHS, linked NHIS–HUD data sample, 2012; HUD administrative data, 2012. 

Figure II. All 2012 HUD-assisted tenants and concurrently linked 2012 NHIS–HUD participants, by sex and age group

Page 28   Series 1, No. 60

Evaluation of Linked 

2009–2012 NHANES–HUD 

40

95% CI

All 2012

2012 NHIS–HUD linked

HUD-assisted

and concurrent

Data: Results

tenants

participants

A total of 782 NHANES 2009–2012 

30

participants were concurrently linked 

to HUD administrative data. During 

the 2009–2012 time frame, the HUD 

administrative records contained data 

20

on 14,148,465 HUD recipients. Results 

Percent

are presented in Appendix Table III and 

26.2

Appendix Figures V–VIII. 

21.0

18.6

18.3

In both populations, the HCV 

10

program was the most common housing 

assistance program. Compared to all 

2009–2012 HUD-assisted tenants, 

0

concurrent 2009–2012 NHANES–HUD 

Households with disabled persons

Households with elderly persons

participants received more assistance 

through HCV programs (60.4% 

NOTES: CI is confidence interval. HUD is U.S. Department of Housing and Urban Development; NHIS is National Health Interview Survey. All variables shown are based on HUD administrative data.

compared to 54.3%, respectively) and 

SOURCES: NCHS, linked NHIS–HUD data sample, 2012; HUD administrative data, 2012.

fewer received assistance through MF 

(17.6% compared to 20.9%) and PH 

Figure III. All 2012 HUD-assisted tenants and concurrently linked 2012 NHIS–HUD 

programs (22.0% compared to 24.7%). 

participants, by percentage of households with disabled or elderly persons The percentages of concurrent 

2009–2012 NHANES–HUD participants 

that were female (65.2%) and male 

of the five age categories, no differences 

45–61 compared with all 2009–2012 

(34.8%) were consistent with those of 

were observed between the two populations.  HUD-assisted tenants (18.4% compared to all 2009–2012 HUD-assisted tenants 

However, more concurrent 2009–2012 

13.7%), and fewer were aged 18–29 (13.6% 

(females 61.6%, males 38.4%). For three  NHANES–HUD participants were aged 

compared to 17.2%).

60

95% CI

All 2012

2012 NHIS–HUD

HUD-assisted

linked and concurrent

tenants

participants

50

40

30

Percent

20

36.2

30.0 32.8

34.7

10

21.5 20.3

22.7 23.1

18.7 20.0

20.2 21.5

17.6 17.9

20.8 17.4

12.3 12.2

0

0–1

2

3

4 or more

1

2

3

4

5 or more

Number of bedrooms

Total household members

NOTES: CI is confidence interval. HUD is U.S. Department of Housing and Urban Development; NHIS is National Health Interview Survey. All variables shown are based on HUD 

administrative data.

SOURCES: NCHS, linked NHIS–HUD data sample, 2012; HUD administrative data, 2012. 

Figure IV. All 2012 HUD-assisted tenants and concurrently linked 2012 NHIS–HUD participants, by household characteristics

Series 1, No. 60   Page 29 

Table III. Number and percent distribution of concurrently linked 2009–2012 NHANES–HUD participants and 2009–2012 HUD-assisted tenants, by HUD program and selected HUD-collected demographic characteristics 2009–2012 concurrently linked 

2009–2012 HUD-assisted 

NHANES–HUD participants 

tenants

( n = 782)

95% CI

HUD program and  

Percent 

demographic characteristics

n

Percent

n

(weighted)

Low

High

HUD housing category

Housing Choice Voucher  . . . . . . . . . . . . . . . . . . . . . . .

7,685,573

54.3

436

60.4

48.5

71.2

Multifamily housing . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2,962,641

20.9

167

*17.6

11.9

25.2

Public housing  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3,500,251

24.7

179

22.0

12.9

34.9

Sex

Male  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5,436,525

38.4

317

34.8

30.7

39.2

Female  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8,710,946

61.6

465

65.2

60.9

69.4

Age group (years)

0–17  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5,683,455

40.2

332

37.3

31.5

43.4

18–29  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2,431,653

17.2

79

13.6

10.5

17.4

30–44 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1,897,090

13.4

79

13.8

11.7

16.2

45–61 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1,935,830

13.7

111

18.4

15.3

21.9

62 and over. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2,200,128

15.6

181

17.0

12.8

22.2

Households

With disabled persons  . . . . . . . . . . . . . . . . . . . . . . . . .

3,588,153

25.4

151

23.2

17.1

30.6

With elderly persons . . . . . . . . . . . . . . . . . . . . . . . . . . .

2,508,121

17.7

195

18.9

14.4

24.5

Unit size (number of bedrooms)

0–1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2,974,052

21.0

182

20.4

14.8

27.6

2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4,142,288

29.3

189

23.8

18.6

29.9

3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5,246,890

37.1

320

45.3

40.2

50.5

4 or more  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1,785,235

12.6

91

*10.5

6.9

15.6

Total household members

1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3,166,498

22.4

201

23.8

18.2

29.3

2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2,443,175

17.3

122

14.6

11.8

18.0

3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2,897,762

20.5

158

21.7

17.2

27.1

4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2,577,165

18.2

132

19.3

14.9

24.5

5 or more  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3,045,711

21.6

162

21.1

14.8

29.2

* Figure may be statistically unreliable because it is based on fewer than 8 degrees of freedom. 

NOTES: Confidence intervals (CIs) for percentages are calculated using SUDAAN with the Korn-Graubard adjustment to the Clopper-Pearson method.  NHANES is National Health and Nutrition Examination Survey, and HUD is U.S. Department of Housing and Urban Development.

SOURCES: NCHS, linked NHANES–HUD data sample, 2009–2012;  HUD administrative data, 2009–2012.

Page 30   Series 1, No. 60

Similar percentages of all 2009–2012 

80

95% CI

All 2009–2012

2009–2012 NHANES–HUD

HUD-assisted tenants (25.4%) and 

HUD-assisted

linked and concurrent

concurrent 2009–2012 NHANES–HUD 

70

tenants

participants

participants (23.2%) lived in a household 

containing a disabled person. Consistent 

60

with the population of all 2009–2012 

HUD-assisted tenants (17.7%), 18.9% of 

50

concurrent 2009–2012 NHANES–HUD 

t

participants lived in a household containing 

40

an elderly person. The distribution of unit 

Percen

60.4

size differed between the two populations 

30

54.3

for all categories except the 0–1 number 

20

of bedrooms category. The distribution 

of total household members was similar 

24.7

10

20.9

22.0

between the two populations except for the 

17.6

category with a household size of two: The 

0

population of all 2009–2012 HUD-assisted 

Housing Choice

Multifamily housing

Public housing

Vouchers

tenants had more individuals living in 

HUD housing category

households with a size of two (17.3%) than 

NOTES: CI is confidence interval. HUD is U.S. Department of Housing and Urban Development; NHANES is National the population of concurrent 2009–2012 

Health and Nutrition Examination Survey. All variables shown are based on HUD administrative data.

NHANES–HUD participants (14.6%).

SOURCES: NCHS, linked NHANES–HUD data sample, 2009–2012; HUD administrative data, 2009–2012. 

Figure V. All 2009–2012 HUD-assisted tenants and concurrently linked 2009–2012 

NHANES–HUD participants, by HUD housing category

80

95% CI

All 2009–2012

2009–2012 NHANES–HUD

HUD-assisted

linked and concurrent

tenants

participants

70

60

50

40

Percent

65.2

30

61.6

20

38.4

40.2

34.8

37.3

10

17.2

18.4

13.6

13.4

13.7

15.6

17.0

13.8

0

Male

Female

0–17

18–29

30–44

45–61

62 and over

Sex

Age group (years)

NOTES: CI is confidence interval. HUD is U.S. Department of Housing and Urban Development; NHANES is National Health and Nutrition Examination Survey.

All variables shown are based on HUD administrative data.

SOURCES: NCHS, linked NHANES–HUD data sample, 2009–2012; HUD administrative data, 2009–2012. 

Figure VI. All 2009–2012 HUD-assisted tenants and concurrently linked 2009–2012 NHANES–HUD participants, by sex and age group

Series 1, No. 60   Page 31 

Conclusion 

noninstitutionalized U.S. population 

overall population of HUD assistance 

living in HUD-assisted housing at some 

recipients. Among concurrent linked 

The linked NCHS–HUD data 

point in the administrative period and 

NHIS–HUD and NHANES–HUD 

represent a sample of the civilian 

may or may not be comparable to the 

participants, the percentages of males 

and females and the percentage of those 

living in a household with an elderly 

40

95% CI

All 2009–2012

2009–2012 NHANES–HUD

person were similar to the corresponding 

HUD-assisted

linked and concurrent

percentages among all HUD tenants. 

tenants

participants

Differences between the two populations 

were observed by program category 

30

of HUD housing assistance received, 

age, household disability status, size 

of unit, and total number of household 

members. Differences in characteristics 

20

that were not measured here (e.g., 

Percent

income and health insurance coverage, 

25.4

among others) between concurrent linked 

23.2

10

survey participants and the population 

17.7

18.9

of HUD housing assistance recipients 

should also be taken into consideration. 

These differences may impact the 

0

generalizability of study results from 

Households with disabled persons

Households with elderly persons

analyses of the linked NCHS–HUD data 

NOTES: CI is confidence interval. HUD is U.S. Department of Housing and Urban Development; NHANES is National to the overall population of HUD housing 

Health and Nutrition Examination Survey. All variables shown are based on HUD administrative data.

assistance recipients.

SOURCES: NCHS, linked NHANES–HUD data sample, 2012; HUD administrative data, 2012.

Figure VII. All 2009–2012 HUD-assisted tenants and concurrently linked 2009–2012 

NHANES–HUD  participants, by percentage of households with disabled or elderly persons 60

95% CI

All 2009–2012

2009–2012 NHANES–HUD

HUD-assisted

linked and concurrent

tenants

participants

50

40

30

Percent

45.3

20

37.1

29.3

10

21.0

22.4 23.8

20.4

23.8

21.7

17.3

20.5

18.2 19.3

21.6 21.1

12.6

14.6

10.5

0

0–1

2

3

4 or more

1

2

3

4

5 or more

Number of bedrooms

Total household members

NOTES: CI is confidence interval. HUD is U.S. Department of Housing and Urban Development; NHANES is National Health and Nutrition Examination Survey. All variables shown are based on HUD administrative data.

SOURCES: NCHS, linked NHANES–HUD data sample, 2009–2012; HUD administrative data, 2009–2012. 

Figure VIII. All 2009–2012 HUD-assisted tenants and concurrently linked 2009–2012 NHANES–HUD participants, by household characteristics

Vital and Health Statistics 

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DHHS Publication No. (PHS) 2018–1336, Series 1, No. 60

CS281153

Document Outline

Contents

Detailed Tables

Text Figures

Appendix Tables

Appendix Figures

Acknowledgments

Abstract

Background

Methods

Conclusions

Introduction

Data Sources

NHIS

NHANES

HUD Administrative Data

Public and Indian Housing Information Center

Tenant Rental Assistance Certification System

HUD transaction dates included in NCHS–HUD administrative period

Data Linkage Approval, Eligibility, and Process

Linkage Approval and Eligibility

Linkage Process

Linked NCHS–HUD Data

General Description of Linked Data Files

NHIS–HUD and NHANES–HUD public-use feasibility files

NCHS–HUD restricted-use transaction file

NCHS–HUD restricted-use episode files

NCHS–HUD restricted-use concurrency file

NCHS–HUD restricted-use sample weights file

Access to Linked NCHS–HUD Data Files

Analytic Considerations

Sample Weights

Analyses Using Linked NCHS–HUD Data

Descriptive Analyses of Linked NHIS–HUD and NHANES–HUD Participants

Conclusion

Published Research Papers Using NCHS Surveys Linked to HUD Data

References

Appendix I. U.S. Department of Housing and Urban Development’s Largest Housing Assistance Programs

Housing Choice Vouchers and Related Programs

Multifamily Programs

Public Housing

Appendix II. Summary of Linked National Center for Health Statistics–U.S. Department of Housing and Urban Development Data

Appendix III. Data Variable Considerations

Concurrency by Program (HCV, MF, PH)

Concurrency at survey interview

Concurrency at examination (NHANES only)

Concurrency by Subprogram (non-MTW HCV, MTW HCV, non-MTW PH, MTW PH, PBS8 MF, non-PBS8 MF)

Concurrency at survey interview

Concurrency at examination (NHANES only)

HUD Transactions Occurring After Survey

Number of days between interview and next HUD transaction

Number of days between examination and next HUD transaction (NHANES only)

HUD Transactions Occurring Before Survey

Number of days between interview and previous HUD transaction

Number of days between examination and previous HUD transaction (NHANES only)

Appendix IV. Evaluation of NCHS–HUD Data Linkage: Comparison With HUD Program Recipients

Evaluation of Linked 2012 NHIS–HUD Data: Methods

Evaluation of Linked 2012 NHIS–HUD Data: Results

Evaluation of Linked 2009–2012 NHANES–HUD Data: Methods

Evaluation of Linked 2009–2012 NHANES–HUD Data: Results