This project is funded by CLOSER, whose mission is to increase the visibility, use and impact of social and biomedical longitudinal population studies to ensure that longitudinal data and research are used to address the challenges facing the UK, now and in the future. CLOSER is funded by the Economic and Social Research Council (ESRC; grant reference: ES/K000357/1). The funder took no role in the design, execution, analysis or interpretation of the data or in the writing up of the findings.
This resource report is part of a broader work package (CLOSER Work Package #19 ‘Assessment and harmonisation of cognitive measures in British birth cohorts’), that was supported by CLOSER’s Innovation Fund. This initiative supported research that sought to enhance and extend the research possibilities of data from different longitudinal population studies in the UK.
Data harmonisation is the process of making data from different studies more comparable. By harmonising data from different UK longitudinal studies, researchers will be able to pool data from multiple studies, an exercise that has many benefits, e.g. increased sample sizes or increased heterogeneity of samples. Moreover, data harmonisation provides us with the opportunity to examine factors that may account for between-study differences, thereby providing insight into societal changes over time.
This project brings together data from five British birth cohorts: i) Medical Research Council (MRC) National Survey of Health of Development (NSHD); ii) the 1958 National Child Development Study (NCDS); iii) the 1970 British Cohort Study (BCS70); iv) the Avon Longitudinal Study of Parents and Children (ALSPAC); and v) the Millennium Cohort Study (MCS). The NSHD is funded by the Medical Research Council and hosted by the MRC Unit for Lifelong Health and Ageing at UCL. The NCDS, BCS70, and MCS receive core funding from the ESRC, and are hosted by the Centre for Longitudinal Studies, UCL. The NCDS sweep at age 62 was co-funded by the MRC, the US National Institutes of Health and the Department for Work and Pensions. The most recent sweep of the BCS70 Age 46 sweep received additional funding from the MRC and the British Heart Foundation. The ALSPAC receives core funding from the MRC, the Wellcome Trust, and the University of Bristol, and is hosted by the University of Bristol.
The authors would like to thank the owners of the five studies included in this report, and the cohort members and their families who have given their time to take part in these studies. We would also like to acknowledge the UK Data Service for providing access to the NCDS, BCS and MCS. With regards to the NSHD and ALSPAC, we would like to thank the following individuals for their help in gaining access to the relevant data:
- NSHD – Dr Philip Curran and Mr Adam Moore, MRC Unit for Lifelong Health and Ageing, UCL
- ALSPAC – Dr Sian Crosweller, Population Health Sciences, Bristol Medical School, University of Bristol
The updates in version 2 of this guide were carried out by Dr Charlotte Campbell at CLOSER alongside Katie Sykes and Sude Işıl Baştuğ who were supported by a CLOSER internship in 2024.