The Kids’ Environment and Health Cohort will be a research-ready, anonymised national birth cohort of all children born in England from 2006  onwards held in a secure data safe haven at the Office for National Statistics (ONS). The Kids’ Environment and Health Cohort will hold linked administrative data (from vital statistics, Census and health and education data) to geo-environmental data nationally over time, following children during pregnancy, and from birth until adolescence. The cohort will become a data resource with sufficient size and geographical variation in environmental exposures to facilitate evaluation of the impact of changes to homes and neighbourhood environments over time in children overall, as well as in specific high-risk groups. The cohort will provide a multitude of uses for cutting-edge research in environmental and social epidemiology, including exploring wider, long-term pandemic impacts, or the effects of climate change or Net Zero policies acting via homes or local environments on children’s health and education.

Children will be linked to their mothers’ hospital admission records to allow researchers to take into account the impact of maternal conditions and pregnancy health on child health and education outcomes, and examine pathways, for example between exposure to air pollution and subsequent child health. It will also be possible to link children to their siblings allowing researchers to perform sibling control studies which have been suggested as a method for reducing bias due to familial risk factors in cohort studies of environmental impacts on children.

The following data sources will be linked to construct the Kids’ Environment and Health Cohort:

The project involves linking the following datasets:

• ONS birth and death registration data

• Census 2011 and 2021 data: children born within two years of each Census
• Hospital Episode Statistics: contains data on hospital contacts
• Maternity Services Data: holds data on maternal health during pregnancy
• Mental Health Dataset: holds information on referrals to mental health services
• Community Dispensing Data: information on dispensed medicines, including for asthma
• National Pupil Database: which holds data on all children in state school, including special educational needs provision and exam results
• Personal Demographic Service (NHS address records) and Getting Information About Schools Data (school addresses). These will be used by the ONS to link data on the local environment to children’s data.

In addition to the linked administrative data, a number of open environmental datasets (including Department for Environment Food and Rural Affairs modelled annual air pollution, Department for Transport Annual Traffic Flow, and Department for Levelling Up, Ordnance Survey Open Greenspace database, Housing and Communities Energy Performance Certificate data) will also be mapped to the Kids’ Environment and Health Cohort at set up. This will allow research on the impacts of air pollution, building characteristics, local neighbourhood, and road distance on child outcomes.

Linkage to the Personal Demographic Service (NHS addresses) and Getting Information About Schools Data will allow derivation of longitudinal records of current and past home and school postcodes and unique property reference numbers (UPRNs; a unique ID for each property throughout England) . Geo-environmental data mapped to UPRNs or postcodes can then be linked to the cohort via these longitudinal address records. 

All residential postcodes and UPRNs, and school postcodes will be securely held by the ONS, separately from data available in the Kids’ Environment and Health Cohort. Linkage to geo-mapped environmental data will be done using encrypted UPRNs, postcodes and school IDs; these geographical identifiers will not be accessible by researchers.

There are currently 585,000 live births in England annually and therefore the total cohort will include data for around 11 million children. This large sample size and national coverage will ensure sufficient statistical power and geographical variation for a variety of analyses.

The Kids’ Environment and Health Cohort will be stored in the ONS Secure Research Service, from where researchers can access the data. Researchers will need to demonstrate that they meet a number of criteria, including being ONS Approved Researchers, favourable research ethics review etc. Further information about how to apply to access the data will be published here in due course.