The cohort will link the following datasets in two stages:

For the Stage 1, the following data will be linked:

• Office for National Statistics (ONS) birth and death registration data
• Census 2011 and 2021 data for mothers for children born within two years of each Census
• Department for Environment Food and Rural Affairs modelled Annual Air Pollution data
• Met Office data on air temperature
• Ministry of Housing, Communities and Local Government: Energy Performance Certificate data
• Valuation Office Agency data on property type and valuation
• Access to private gardens and public greenspaces

The environmental data will be linked to the birth records via the address on the birth registration dataset.

For Stage 2, the following data will be linked:

• NHS birth notification data
• NHS Hospital Episode Statistics: data on hospital admissions and attendances
• NHS Maternity Services Dataset: data on maternal health during pregnancy
• DfE National Pupil Database: data on all children in state school, including special educational needs provision and exam results
• NHS Personal Demographic Service / Patient Register (NHS address records) and School Address Data from Department for Education (school addresses): used by the ONS to link data on the local environment to children’s data at each home and school address. 

In the future, we will aim to link to the following datasets:

• NHS Mental Health Services Dataset: information on referrals to mental health services
• NHS Community Dispensing Data: information on dispensed medicines, including for asthma

The data will be linked subject to approvals from the ONS, , NHS England and the Department for Education.

Research potential of the Kids’ Environment and Health Cohort

The Kids’ Environment and Health Cohort will enable research on how changing local environments impact children’s health and education, which can be used to inform government departments, local councils, and the public. It will also enable new insights into how well housing, environmental, and planning policies are working to improve children’s lives.

Phase 1 will be particularly suited to addressing research objectives related to the impact of housing quality, temperature, greenspace access and air pollution on birth outcomes, and perinatal, infant and child mortality.

Linkage to health data

For the time being, NHS data will only be analysed by ONS and UKSA (National Statistician’s Office) for carrying out the KEHC demonstrator study on overcrowding and infant health, pending discussions with NHS England for data to be made available on SRS.

Linkage to further environmental datasets

Researchers will not have access to data on the geographical location of children’s homes and schools. Indirect linkage to data from the Personal Demographic Service/Patient Register (NHS addresses), addresses on birth records and school addresses via the ONS will allow the cohort to be linked to further, researcher supplied, longitudinal geo-environmental data mapped to postcodes and unique property reference numbers (UPRNs; a unique ID for each property throughout England) of homes and schools across the child’s life. This will be part of stage 2 of Kids’ Environment and Health Cohort. 

All residential postcodes and UPRNs and school postcodes will be securely held by the ONS, separately from the Kids’ Environment and Health Cohort data. 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.

Data access

The Kids’ Environment and Health Cohort will be stored in the ONS Secure Research Service (SRS), a national Trusted Research Environment. 

Before gaining access to the Kids’ Environment and Health Cohort data, researchers will need to meet certain requirements. These are still being discussed with data providers, but are likely to include:

• Researchers will need to be considered Accredited Researchers 
• Researchers will need to undertake further training, depending on the constituent datasets requested
• Researchers need to obtain ethical approval and sign agreements with UCL before accessing the data