Intercensal denominators - feasibility of using the Labour Force Survey to estimate mortality rates by NS-SEC

The purpose of this analysis is to investigate the feasibility of using the Labour Force Survey (LFS) to provide population denominators for the estimation of mortality rates by the National Statistics Socio-economic Classification (NS-SEC). This is in order to contribute to the monitoring of health inequalities over time. Currently it is possible to produce mortality rates only at the time of a census when populations are enumerated by occupation and NS-SEC.

The Labour Force Survey (LFS) was used to provide population denominators by age, sex and NS-SEC for various time periods. Numerators for mortality rates were derived by obtaining aggregate deaths by age group and NS-SEC analytic class for men aged 25-64. Standardised mortality rates were then derived. Results for 2001-03 were compared with published estimates which used 2001 Census-based denominators.

Significant differences were detected for most NS-SEC classes between mortality rate estimates, based on the 2001 Census, and those based on the contemporary LFS dataset. However the results for different years, based on LFS denominators, suggest that a series of mortality rates using LFS-based denominators appeared to have internal consistency. The LFS-based estimates showed a statistically significant decrease in mortality rates between the periods 2001-03 and 2005-07, across all but one NS-SEC classes. The precision of LFS-based estimates at different levels of geography was also assessed in order to determine the feasibility of using these estimates to monitor inequalities at sub-national level.

The LFS can be used to produce regular population denominators for the estimation of mortality rates, to assess health inequalities by NS-SEC for men at the level of England & Wales, both on an annual basis and over three-year time periods. It is recommended that, in order for the LFS-based estimates to be effective over time, they would have to be related to each other rather than to the census-based ones. At the level of Government Office Region (GOR), it would also be possible to do this, but on a three-year period basis only. Below this level of geography, estimates would be insufficiently precise. Information exists on the LFS to produce a similar analysis for women.