The sample for the Active Lives survey was selected from the Postcode Address File (PAF) – a list of all postal addresses in the United Kingdom maintained by Royal Mail.
There are no other sampling frames that give the coverage and ease of use of the PAF.
The PAF is a list of addresses and contains no information about residents at addresses. Hence the need to send the survey materials to the address without names, and to issue instructions about selecting up to two adults within each selected address (see section on household sample design for further information on this process).
Because the samples were un-clustered within each local authority, the sample was selected as a systematic sample with the PAF addresses in postcode order. This was to ensure a good spread of addresses across the local authorities.
The sampling was designed to achieve pre-determined numbers of returns from adults within each local authority across the year of the survey.
For the majority of the local authorities (180 of 296), the target number of completed questionnaires was 400 returns.
From the baseline of 400, boosts were added for certain local authorities either based on their population size or based on need.
Lastly, local authorities could purchase additional sample to enable them to conduct deeper analysis on the data. The target for each local authority can be found in the Appendix.