Overview
Aims
The Avon Longitudinal Study of Parents & Children (ALSPAC) is a multi-generational, population-based prospective birth cohort study. Established in the early 90s, ALSPAC follows the lives of over 14,500 people born between April 1991 and December 1992 and their family members. Children and their families have been followed intensively, primarily with annual questionnaires, as well as clinical assessments for a sub-sample of cohort members. ALSPAC was specifically designed to understand the ways in which genetic and environmental factors interact to influence health, behaviour, and development across the lifespan.
The ALSPAC study has collected data using a range of methods. Mental health measures collected in postal questionnaires and from clinic assessments are detailed on the Catalogue.
Institution
University of Bristol
Geographic coverage - Nations
England
Geographic coverage - Regions
Bristol & District Health Authority (Former Avon Health Authority Area)
Start date
1990
Catalogue record last updated
28/03/2024
Sample
Sample type
Pregnancy cohort
Sample details
Pregnant women residing in Avon with an expected delivery date between the 1 April 1991 and the 31 December 1992 were eligible to participate.
The initial sample was recruited during Phase I, in which mothers enrolled in the study during pregnancy and then either returned at least one questionnaire or attended a "Children in Focus" clinic by 19 July 1999. This initial sample consisted of 14,541 pregnancies (14,676 foetuses, with 195 twin, 3 triplet and 1 quadruplet pregnancies), resulting in 14,062 live births. 13,988 children (cohort members) were alive at 1 year of age.
Eligible cohort members who did not join in Phase I have joined the study through major recruitment drives since the cohort members were 7 years old. A further 913 eligible cohort members have been enrolled in this way. As a result of further enrolment during Phases II (7years), III (8 years) and IV (18 years), the baseline sample consists of 15,454 pregnancies (15,589 known foetuses) and 14,901 cohort members alive at 1 year of age.
During pregnancy, partners/fathers were recruited via the mother. More recently, fathers have been recruited directly by the ALSPAC team and via the cohort members. Measures relating to cohort members’ grandparents have also been collected from the cohort members, mothers and fathers.
The study has been extended to include cohort members’ children. This study, known as ALSPAC-Generation 2 (COCO90s), is not currently included in the Catalogue, but more information is available here.
Sample size at recruitment
15,454 enrolled pregnancies
14,901 children (cohort members) alive at 1 year of age
Sample size at most recent sweep
Approximately 4,440 (2020 - Life at 27+)
Sex
All
Age at recruitment
Birth
Cohort year of birth
April 1991 - December 1992
Data
Data access
Project proposal - contact study team
http://www.bristol.ac.uk/alspac/researchers/access/
Genetic data collected
Linkage to administrative data
Education data Environmental data Health data Social media data
Additional information
Website
bristol.ac.uk/alspac
Notes
Also known as Children of the 90s (CO90s).
Related themes
Covid-19 data collection,
Biomarkers,
Cognitive measures,
Diet and nutrition,
Education,
Ethnicity and race,
Sexuality and gender identity,
Housing,
Socioeconomic status and deprivation,
Language and literacy,
Loneliness and social isolation,
Neighbourhood,
Physical health assessment,
Political and social attitudes,
Digital technology and social media,
Victimisation and life events,
Puberty,
Reproductive health,
Work and employment,
Parenting and family,
Sleep problems,
Social care - receipt,
Social care - provision,
Social care - need
Summary
ALSPAC is a birth cohort study that was designed to assess how genes and the social and physical environment influence health, behaviour and development across the lifespan. The study has been following individuals who were born between 1991-1992 in the Bristol area, and their families, with annual questionnaires and clinical assessments.
Key Papers
Cohort profile: the ‘children of the 90s’—the index offspring of the Avon Longitudinal Study of Parents and Children. doi.org/10.1093/ije/dys064 The Avon Longitudinal Study of Parents and Children (ALSPAC): an update on the enrolled sample of index children in 2019. doi.org/10.12688/wellcomeopenres.15132.1 Fraser et al. (2013). Cohort profile: the Avon Longitudinal Study of Parents and Children: ALSPAC mothers cohort. doi.org/10.1093/ije/dys066 Smith et al. (2021). The Avon Longitudinal Study of Parents and Children - A resource for COVID-19 research: Questionnaire data capture November 2020 – March 2021. doi.org/10.12688/wellcomeopenres.16950.1
Mental health measures timeline
Sweep name:
Cohort member age:
Data collection period:
Notes:
Physical health measures: