Millennium Cohort Study (MCS)

Summary of cohort

The Millennium Cohort Study (MCS), also known as ‘Child of the New Century’ is the youngest of the UK’s current birth cohort studies.

MCS is a study of all children born between September 2000 and January 2002 in 398 areas across England, Scotland, Wales and Northern Ireland who were alive and living in the UK at 9 months and eligible to receive child benefit [142].

The original sample consisted of 18,552 families (18,827 children).

In 2003-2004 during the survey at age three (MCS2), the sample was boosted by families in England who were eligible for inclusion in MCS1 but were missed. The boost brought the total number of children taking part to 19,517 [143].  A stratified cluster sampling framework was used to adequately represent families from disadvantaged areas and ethnic minority groups.

There have been six data collections to date: age 9 months, 3, 5, 7, 11, 14 and 17 years. A range of social, economic, demographic and health information have been collected and the data have been linked to administrative data resources.

The MCS was included in the COVID-19 waves of data collection in the British birth cohorts. A web-based interview was carried out in May 2020 (Wave 1), September-October 2020 (Wave 2), and February-March 2021 (Wave 3), when MCS members were aged 20 years.