Birth to Thirty (Bt30)
The Bt30 sample consists of around 3,000 singleton children born within a 7-week enrolment window in 1990, to mothers residing in Soweto-Johannesburg, South Africa. Mothers were recruited at public clinics and must have remained in the area up until the child reached 6 months of age. At the start in 1990, the study was called Birth to Ten (BT10), but changed to Birth to Twenty (BT20) in 2000. As of March 2024, the study is still ongoing and has completed over 22 waves of data collection from participants and their caregivers.
Study design
Cohort - birth, Cohort - primary caregiver and child
Number of participants at first data collection
3,273 (participants)
Age at first data collection
Varied (mothers)
Birth (children)
Participant year of birth
1990 (participants)
Participant sex
All
Representative sample at baseline?
No
Sample features
Country
Year of first data collection
1990 (participants)
1989 (pregnant mothers)
Primary Institutions
Emory University
University of Oxford
University of the Witwatersrand, Johannesburg
Profile paper DOI
Funders
Anglo-American Chairman’s Fund
Bill & Melinda Gates Foundation
DSI-NRF Centre of Excellence in Human Development (CoE-Human)
Human Sciences Research Council (HSRC)
Oppenheimer Memorial Trust
Ongoing?
Yes
Data types collected
- Self-report questionnaire – paper or computer assisted
- None
- None
- None
Engagement
Keywords
Consortia and dataset groups
