Sample Type
National area probability sample of community residing adults born between 1920 and 1947 (aged 57 to 85 at the time of the interview) including an oversampling of African-American and Hispanic areas. The NSHAP sample was built on the foundation of the national household screening carried out by the Health and Retirement Study (HRS) in 2004. Through a collaborative agreement, HRS identified households for the NSHAP eligible population. A sample of 4400 people was selected from the screened households. NSHAP made one selection per household. 92 percent of the persons selected for the NSHAP interview were eligible. 75.5 percent of those eligible completed the NSHAP interview.

Sample Size
3,005 completed interviews conducted between July, 2005 and March, 2006

Response Rate
Overall weighted response rate of 75.5 percent

Data Collection Method
NSHAP data collection consists of three distinct components:
(1) In-person questionnaire
(2) Biomeasure collection
(3) Supplemental self-administered questionnaire (SAQ)

The in-person questionnaire and biomeasures were administered by a NORC field interviewer in the respondent’s home. Questionnaire topics included: 1) demographic characteristics; 2) social networks; 3) social and cultural activity; 4) physical and mental health including cognition; 5) well-being; 6) illness; 7) medications and alternative therapies; 8) history of sexual and intimate partnerships; and 9) patient-physician communication.

Thirteen biomeasures were collected in NSHAP: 1) height; 2) weight; 3) waist circumference; 4) blood pressure; 5) smell; 6) saliva; 7) taste; 8) respondent-administered vaginal swabs; 9) oral mucosal transudate (OMT); 10) vision; 11) ‘get up and go’; 12) touch; and 13) blood spots. The biomeasures included in NSHAP were specifically designed to be implemented by non-medically trained interviewers. The data collection protocols were minimally invasive and safe for both interviewer and respondent.

At the end of the in-person interview, respondents were given a supplemental paper-and-pencil questionnaire. Respondents were asked to complete this questionnaire and return it via U.S. mail in a provided postage-paid envelope. Approximately 84 percent of respondents returned the supplemental questionnaire.

Modularization
The NSHAP interview was modularized to minimize in-home interview time and reduce respondent burden. The in-home interview was comprised of a series of core and modular items. All respondents received the core questions and biomeasures. The remaining questions and biomeasures were modularized. The modules were randomly pre-assigned to a subset of respondents. The modularized questions that were not administered to a subset of respondents during the in-person interview were captured in supplemental SAQ.

Average Length of Interview
About 120 minutes for the in-person interview, which included the in-person questionnaire and biomeasures. The supplemental SAQ took approximately 30 minutes or less to complete.

Respondent Communication
If you are a NSHAP respondent and would like to contact us, you may call NSHAP toll-free at 1-866-309-0540 (English) or 1-866-291-2955 (Spanish).

Return to NSHAP home page.