Project Summary
This project, developed in response to RFA-AG-21-008, describes core plans for data collection and
dissemination of the sixth wave (Wave VI) of the National Longitudinal Study of Adolescent to Adult Health
(Add Health), when cohort members will be 39-48 years of age (mean 44). Add Health is a longitudinal study of
a nationally representative sample of over 20,000 adolescents who were in grades 7-12 during the 1994-95
school year and have been followed for five waves to date. Over 25 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; administrative data linked to participants, including birth and death certificates; and
in-home physical and biological data from participants, including anthropometric measures, genetic markers,
blood-based assays, and medications. Ancillary studies have added more information, including epigenetic,
gene expression, and microbiome data. Thus, Add Health is exceptionally unique because it has a rich, multi-
level, longitudinal array of data for a large nationally representative cohort of Americans who are entering
midlife. Importantly, the overall health profile of the cohort as they make the transition to midlife is problematic
across many dimensions. Moreover, health disparities by race, ethnicity, gender, socioeconomic status, sexual
minority status, and rural-urban residence in this cohort are wide and, in some cases, widening. As such, rich
longitudinal, multi-level, and nationally representative data are urgently needed to best understand the life
course determinants of health trajectories and health disparities of US adults as they enter midlife. Wave VI of
Add Health will fill this critical need. The overall goal of Wave VI of Add Health is to collect and disseminate the
comprehensive data needed to best understand the social, economic, psychosocial, contextual, and biological
determinants of health trajectories and disparities among this nationally representative cohort of Americans as
they age into midlife. The project is focused around five aims: 1) Re-interviewing cohort members using
predominantly web-based and in-person modes, with explicit attention to securing high response rates from
racial/ethnic minority and low socioeconomic status participants; 2) Enriching study content in key domains that
will elucidate mid- and later-life health trajectories and disparities; 3) Re-visiting cohort members who consent
for an in-home health exam that includes venous blood collection and other important components of health; 4)
Assaying biological specimens for important pre-disease and disease biomarkers; and 5) Cleaning,
documenting, disseminating, archiving, promoting, and supporting Wave VI data for the scientific community.
This project has extraordinary potential to contribute to the science of aging, health, and health disparities for
decades to come, as the Add Health cohort ages into the middle adult years and beyond. Successful carryout
of this project will supply essential data for thousands of researchers working on these critical issues.