Quality assurance of data

Every quarter PHE publishes data returned by all local authorities on the number of NHS Health Checks offered and the number of checks received. This data is an official statistic and is used in the calculation of the NHS Health Check indicators on the Public Health Outcomes Framework  and in the NHS Health Check profile.

As the data returned by local authorities is an official statistic PHE have a duty of care to follow a code of conduct regarding the production, management and publication of the data. In fulfilling part of that duty analysts quality assure the data by applying statistical rules, agreed by the NHS Health Check data intelligence and information governance group. This ensures that errors and inaccuracies are detected and followed up with the nominated person in a local authority. 

Through this quality assurance process we have identified a particular challenge with the way invitations are reported in some areas. In addition to counting the first invitation, some areas are also counting reminder letters or prompts to individuals. Reminders, prompts and follow-up invites to people that have already been invited for a check should not be included in the quarterly data returns. An invitation is ‘per individual every five years,’ so second and third invitations to the same person within that time should not be included in quarterly returns.

This means that the rate of invitations seems extremely high. This is not only misleading, but also dilutes local authorities’ take up rate, since take up is calculated as ‘number of people having a check divided by the number of people offered a check’.