Wave III

The in-home Wave III sample consists of Wave I respondents who could be located and re-interviewed during the field-work period, August 2001 to April 2002, when they were between 18 and 26 years old*. Interviews with 15,170 Wave I respondents were completed at Wave III.

Wave I respondents who were out of the country were omitted from Wave III. Every effort was made to re-interview respondents who were located in correctional facilities.

*24 respondents were 27-28 years old at the time of interview.

In-Home Interview: Wave III

The Wave III questionnaire was designed to obtain relationship, marital, childbearing, and educational histories, and to date key labor force events. Some questions were unchanged from earlier waves. To enhance longitudinal measures, new sections focus on topics more relevant to young adults. Because respondents are older at Wave III, the social contexts shaping their health outcomes are different from those in earlier waves. For many, college or work contexts are likely to be more important. Dense peer groups associated with school-based networks likely have given way to smaller networks of friends drawn from diverse settings. Relationships with romantic partners likely are more influential as respondents approach decisions about cohabitation and marriage; family effects may be less prominent. Against this complex background of shifting influences, the patterning of genetic expression on health behaviors is also expected to change. Wave III is designed to provide data on these new domains of young adult life, enabling researchers to model the dynamic processes of change over time.

Data collection was conducted nationwide (including Hawaii and Alaska). To maintain confidentiality, no paper questionnaires were used. As in earlier waves, data were recorded on laptop computers. For less sensitive material, the interviewer read the questions and entered the respondent's answers. For more sensitive material, the respondent entered his or her own answers in privacy. The average length of a complete interview was 134 minutes. The laptop interview took approximately 90 minutes and was followed immediately by the collection of biological specimens. Most interviews were conducted in respondents' homes.

Wave III In-Home Questionnaire Sections

• Add Health Picture Vocabulary Test
• Overview and Demographics
• Household Roster and Residence History
• Parental Support and Relationships
• Retrospective ADHD
• Relationships with Siblings
• Friends
• Education
• Labor Market Experience and Active-Duty Military Service
• General Health and Diet
• Access to Health Services, Health Insurance
• Illnesses, Medications, Physical Disabilities
• Social Psychology and Mental Health
• Mentoring
• Marriage/Cohabitation History and Attitudes
• Economics and Personal Future
• Sexual Experiences and STDs
• Table of Relationships
• Table of Pregnancies
• Relationships in Detail
• BEM Inventory
• Propensity for Risk
• Completed Pregnancies
• Current Pregnancies
• Live Births
• Children and Parenting
• Delinquency and Violence
• Involvement with the Criminal Justice System
• Tobacco, Alcohol, Drugs, Self-Image
• Mistreatment by Adults
• Civic Participation and Citizenship
• Religion and Spirituality
• Gambling
• Daily Activities
• Biological Specimen Participation
• Interviewer's Report

Partner Sample: Wave III

Approximately 50 percent of the original sample was flagged to be evaluated for partner recruitment. Recruitment was determined by a computer algorithm that evaluated the relationship history provided by a respondent. Criteria required that a partner be current, of the opposite sex, at least 18 years old, and in a relationship with the original Add Health respondent for at least three months.

A sample of 1,507 partners of respondents was interviewed at Wave III, representing a wide spectrum of relationship intimacy and commitment. The sample consists of one-third married, one-third cohabiting, and one-third dating partners.

Partners In-Home Interview: Wave III

Because partners were being interviewed for the first time, they were asked for name, age, and gender. Questions about previous parent figures, friends, and siblings were not administered to partners.

Special Features of Data Collection at Wave III

Residential latitude and longitude were collected using a GPS device.

Interviews of original Add Health respondents were pre-loaded with some Wave I and Wave II data, including the name, age, and sex of the respondent and identifications of parent figures, friends, and siblings from earlier waves.

A monthly Event History Calendar (EHC) was designed to help respondents remember when events occurred, in a time continuum relative to pre-loaded public events. Important personal or relationship events entered by a respondent were automatically displayed in the calendar, which appeared on screen each time he/she was asked to date an event. The EHC could be accessed at any time during the interview and dates could be corrected after they were entered.

Wave III also collected High School Transcript Release Forms. A separately funded NICHD study used them to collect and code transcript information for Wave III respondents. These files comprise the Education Data component of the Add Health study.

Biological Specimen Collection

At Wave III, Add Health respondents were asked to provide saliva and urine specimens for HIV and STD testing. A subsample of full siblings and twins was also asked to provide a saliva sample for genetic analysis.