PROJECT PAGE
The National Longitudinal Study of Adolescent to Adult Health (Add Health)
The National Longitudinal Study of Adolescent to Adult Health (Add Health) is a large nationally-representative longitudinal study of adolescents. Beginning with an in-school questionnaire administered to a nationally representative sample of students in grades 7-12, the study followed up with a series of in-home interviews conducted in 1995, 1996, 2001-02, 2008, and 2016-18 (5 waves). Add Health participants are now adults, aged 33-44, and will soon be moving into midlife. Over the years, Add Health has collected rich demographic, social, familial, socioeconomic, behavioral, psychosocial, cognitive, and health survey data from participants and their parents; a vast array of contextual data from participants’ schools, neighborhoods, and geographies of residence; and in-home physical and biological data from participants, including genetic markers, blood-based assays, anthropometric measures, and medications. Ancillary studies have added even more data over the years. For more information about the study design, see: https://addhealth.cpc.unc.edu/wp-content/uploads/docs/documentations/2020_Study_Design.pdf.
Principal Investigator(s): Dr. Kathleen Mullan Harris and Dr. Robert A. Hummer
General Information
Country of Data Collection: USA
Years of Data Collection: 1995-present
Study Status: Ongoing
Total Number of Assessments Completed: 5
Approx. Retention Rate: 59% – 76%
Sample
Composition: Nationally Representative; Family Study (parents, partners)
Sex
SES
*Nationally representative
Race/Ethnicity
*Nationally representative
Personality Data
Construct
Big Five
Self-Esteem
Risk Taking
Hostility
Optimism
Scale
Various scales/items*
Abbrev. Rosenberg Self-Esteem Scale
Various items**
NEO-Personality Inventory Anger Facet
3-item Optimism Scale***
Waves
T1, T4, T5
T1, T2, T3
T1, T2, T3, T4, T5
T4
T4, T5
Method
Self-Report
Self-Report
Self-Report
Self-Report
Self-Report
*See Young & Beaujean (2011) for how to create measures of Extraversion, Conscientiousness, and Neuroticism at Time 1. The Mini International Personality Item Pool was administered at Time 4 to assess all Big Five traits. There is an abbreviated Conscientiousness measure at Time 5.
**There is a single item measure of sensation seeking (“I like to take risks” available at Times 2, 3, 4, 5. There is a two-item measure of impulse control (“I go with my gut feeling and don’t think much about the consequences of each alternative” and “I live life without much thought of the future”) available at Times 1, 2, 3, 4; one of the items (“I go with my gut feeling and don’t think much about the consequences of each alternative”) was also asked at Time 5.
***The three items are: “I am always optimistic about my future.”; “I hardly ever expect things to go my way.”; “Overall, I expect more good things to happen to me than bad.”
Academic/school
affect
cognitive ability/iq
genes
Happiness, well-being, life satisfaction
job/work
life events
mental health
neighborhood
parenting
physical health
psychophysiology
relationships
Data Access
Project Website: https://addhealth.cpc.unc.edu/
Codebook Available Online: Yes, https://addhealth.cpc.unc.edu/documentation/codebooks/
Data Available Online: Some — The Add Health data are publicly available, but the public-use data sets contain data for only a subset of the full Add Health sample. Public-use data are available from three different sources: The Odum Institute at UNC, the Inter-university Consortium for Political and Social Research (ICPSR), and the Association of Religion Data Archives (ARDA).
Project Proposal Required to Use Data: Not for publicly available data, but “Restricted-use data” are available for the full Add Health sample by contractual agreement only. These data will be distributed only to certified researchers who commit themselves to maintaining limited access. To be eligible to enter into a contract, researchers must have an IRB-approved security plan for handling and storing sensitive data and sign a data-use contract agreeing to keep the data confidential. To learn more about the restricted-use data and how to apply for restricted-use data, please access the CPC Data Portal. Instructions for submitting an application are available in this document: https://data.cpc.unc.edu/docs/Information_Packet_-_Restricted-Use_-_NEW.pdf.