On the quality variation of primary health care services: a test of the 'inverse care law' for general practice

Tudor Hart's 1971 study, based in Wales, was the first to hypothesise the existence of an inverse relationship which often prevails between those communities with the most pressing health needs and the lack or poor quality of health services provided locally. Over the last thirty years there have been many demonstrations of the validity of Hart's 'inverse care law' in relation to the provision of, and access to, particular services in the primary and secondary health care sectors. In this paper we provide a direct test of the relationship between an aggregate measure of <i>quality </i>of general practitioner (GP) services and a measure of health need of local populations. We examine the variation in quality of GP services, derived from eligibility for sustained quality payments, over the 131 practices of the former Bro Taf Health Authority in South Wales. Using logit regression analysis we have explored the extent to which the local deprivation of practice populations and the size of practice account for the variation in the quality of provision within the authority. The analysis supports the conclusion that the 'inverse care law' is a strong feature of provision. Both the eligibility of GP practices for quality payments and the availability of training practices are significantly higher in the least deprived wards than those in the most deprived ones.