Introduction

The Centre for Longitudinal Studies (CLS) manages four cohort studies for which data is currently available to researchers:

1. The National Child Development Study (NCDS), a birth cohort of individuals born in Britain in a single week of March 1958.
2. The 1970 British Cohort Study (BCS70), a birth cohort of individuals born in Britain in a single week of April 1970.
3. Next Steps, a cohort of English schoolchildren followed from age 13/14 and born in 1989/90.
4. The Millennium Cohort Study (MCS), a birth cohort of individuals born in Britain in 2000/02.

This is the GitHub repository for the cls-data.github.io website which provides R and Stata code for common data management tasks in each of the studies. This include merging files across survey sweeps, reshaping data from wide to long format, and identifying correct identifier variables for observational units in each study (e.g., cohort members, families, parents, and so on).

For background on these studies, please see cohort profile papers (linked above) and the CLS website. Queries on the data can be sent to the CLS Data team.