The new UK National Statistics Socio-Economic Classification (NS-SEC); investigating social class differences in self-reported health status.

BACKGROUND The new UK National Statistics Socio-Economic Classification (NS-SEC) is theoretically based on differences in employment relations and conditions. Differences in employment relations could account for some of the often observed social class differences in health in the United Kingdom. This study investigates the associations of the NS-SEC with a well-validated health outcome measure--the Short Form health survey (SF-36). METHODS Data from the Oxford Healthy Lifestyles Survey III (OHLS III, n = 6,454), a cross-sectional survey of adult men and women aged 18-64 randomly selected from the counties of Berkshire, Buckinghamshire, Northamptonshire and Oxfordshire, were analysed. The associations of the NS-SEC with the SF-36 physical and mental summary scores are investigated in a series of regression models controlling for age, lifestyle factors, housing and neighbourhood conditions. RESULTS There are significant social class differences in the SF-36 physical and mental summary scores after controlling for age. When lifestyle, housing and neighbourhood conditions are controlled for, these differences reduce to non-significance. CONCLUSION The NS-SEC shows significant social class differences in health, further evidence for its construct validity. Social class differences in housing, neighbourhood and lifestyle factors appear to have a large role in understanding class differences in health. As it is grounded in theory, the NS-SEC is likely to prove a valuable tool for explanations of inequalities in health.