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Avon Longitudinal Study of Parents and Children

Established in 1991, the Avon Longitudinal Study of Parents and Children (ALSPAC), also known as Children of the 90s, is a world-leading birth cohort study. Between April 1991 and December 1992 it recruited more than 14,500 pregnant women in the former county of Avon and it has been following the health and development of the parents and their children ever since.

Based at the University of Bristol, ALSPAC is the most detailed study of its kind in the world, providing a rich resource for the study of the environmental, biological and genetic factors that affect health and development.

People born between April 1991 and December 1992 in the former county of Avon and members of their family can take part, even if they’ve since moved out of the area or overseas.

Data is collected via questionnairesclinical assessmentsbiological samples and data linkage. A data dictionary provides an overview of all available data.

In recent years, ALSPAC has started to recruit and collect data on the children of the original children (COCO90s) who number 1,500 (February 2022) and their non-ALSPAC parent. The eldest COCO90 is 14 years old.

Over 2,500 papers have been published using ALSPAC data. Important discoveries include:

  • Anxiety levels doubled in young people following COVID-19 lockdown
  • Provided evidence to help persuade policy makers to support the ‘back to sleep’ campaign to reduce the risk of cot death
  • Eating oily fish in pregnancy can boost a child’s IQ
  • Size zero is bad for bones
  • Some people have a genetic variant that means they don’t produce body odour
  • Time outdoors is good for children’s eyesight
  • Peanut oil in baby creams and lotions can lead to peanut allergy

Management and funding

ALSPAC is funded by the Medical Research Council, the Wellcome Trust and the University of Bristol. It is managed by a team based at the University of Bristol which is led by the scientific director, Professor George Davey Smith; the principal investigator, Dr Nic Timpson and Ms Lynn Molloy, the executive director.

Accessing the data

ALSPAC has governance and access arrangements that comply with MRC data sharing policy. The data is accessible to bona fide researchers by applying through the ALSPAC online proposal system. The ALSPAC access policy describes the process in detail.

The ALSPAC website provides copies of the documentation used in the study. The website also provides a data dictionary and a variable catalogue, to help users make a formal request for data.

CLOSER Discovery

Variables from ALSPAC are available to explore in CLOSER Discovery – our innovative research tool that enables researchers to search, explore and assess data from multiple UK longitudinal population studies.

Users can search through rich metadata, and filter by study, topic and life stage in order to find the relevant data for their investigations.

Start exploring ALSPAC variable metadata in CLOSER Discovery

Cohort profile

Avon Longitudinal Study of Parents and Children:

Fraser, A., Macdonald-Wallis, C., Tilling, K., Boyd, A., Golding, J., Davey Smith, G., Henderson, J., Macleod, J., Molloy, L., Ness, A., Ring, S., Nelson, S.M., Lawlor, D.A.; Cohort Profile: The Avon Longitudinal Study of Parents and Children: ALSPAC mothers cohortInt J Epidemiol 2013; 42 (1): 97-110. doi: 10.1093/ije/dys066

Children of the 90s:

Boyd, A., Golding, J., Macleod, J., Lawlor, D.A., Fraser, A., Henderson, J., Molloy, L., Ness, A., Ring, S., Davey Smith, G.; Cohort Profile: The ‘Children of the 90s’—the index offspring of the Avon Longitudinal Study of Parents and Children. Int J Epidemiol 2013; 42 (1): 111-127. doi: 10.1093/ije/dys064

Introducing ALSPAC

Related content

Visit the study website