Incapacity or unemployment? The utility of an administrative data source as an updatable indicator of population health

Abstract

Despite the availability of mortality data, a lack of annually accessible morbidity information for small geographical areas in England and Wales means that health studies are often restricted to using decennial, self-reported Census measures. Whilst the dissemination of census information has enabled much research, the self-assessment of health can be affected by subjective factors. Administrative data on health related benefit claims, in the form of Incapacity Benefit (IB) data, are more regularly available and claimants are professionally diagnosed. This source may have potential to be an annual small area indicator of population health. In this paper, we examine IB as an indicator of population health at local government district and sub-district levels by investigating distributions and relationships between IB and other health measures from the census and from mortality statistics. We found that relationships in 2001 between IB, census measures and mortality suggest that using IB as an indicator of population health will give similar results, especially with those reporting themselves ‘permanently sick or disabled’ and especially in more urban areas. Time series analysis also suggested that IB was a useful and updateable source of data on population health. However, although IB should be an objective measure as it is professionally diagnosed, willingness to take time off work due to sickness, to consult a doctor or to claim benefits may be affected by cultural and socio-economic factors. On the other hand, IB may be an incomplete count of ill people because some may be unable to claim benefits. Furthermore, strong relationships exist between poor health, mortality and unemployment. We recognise that IB may be hiding unemployment and have inferred an estimate using census data on economic activity to explore the relationship between IB and those reporting themselves to be permanently sick or disabled. This estimate suggests that previous assertions about the relationship between IB and unemployment may have been over zealous. On balance, IB is a useful indicator of relative health for small areas. However, the utility of Incapacity Benefit as an ongoing updatable indicator of population health depends on the future of the benefit system in view of pending reforms.