Estimating disease-specific costs of GP services in Australia

The primary purpose of this paper is to develop estimates of the costs of management by general practitioners (GPs) of specific diseases. The motivation for the project arises from a dearth of knowledge about the costs of GP management of various conditions on a disease-specific basis. In Australia, aggregate data on the Medicare benefits paid for “GP attendances” are provided in the statistical tables accompanying the annual reports of the Health Insurance Commission (e.g. Health Insurance Commission 2000), but these data do not report the total fees charged by GPs and are not available on a disease-specific basis. The present study uses data available from a nationally representative sample of GPs – the Australian Morbidity and Treatment Survey (AMTS) – combined with information provided by the (then) Commonwealth Department of Human Services and Health and the Department of Veterans’ Affairs, to estimate disease-specific costs of GP services. The AMTS, undertaken by the (then) Family Medicine Research Unit at the University of Sydney over the twelve month period from October 1990 to September 1991, contains data on the problems managed at GP encounters (up to four per encounter), the medications prescribed and treatments provided for each of those problems, and the pathology, radiology and other tests ordered at each encounter. A (single) Medicare item number was also recorded for each encounter (Bridges-Webb et al, 1992). These data can be used, in conjunction with data on the average price charged by item number supplied by the two Commonwealth Departments just mentioned, to investigate the costs of management by GPs of specific conditions.