To the Editor: Studies investigating the relationship between socioeconomic status (SES) and use of healthcare services suggest that, in metropolitan regions, low-SES groups consult general practitioners more frequently than high-SES groups.1 The primary reason is their poorer health and hence greater medical need (however, distributional, operational and financial factors associated with the provision of general practice services are also important).

Is a similar relationship found between SES and GP use in non-metropolitan areas? We investigated this issue using data from the Social health atlas of Australia project.2 We defined “GP use” as unreferred services3 provided by general and vocationally registered practitioners (not specialist medical practitioners), delivered at a surgery or clinic, a patient’s home, or an institution such as a hostel or nursing home.

Specifically, 952 statistical local areas (SLAs), comprising 98.6% of all SLAs for the six Australian states, were classified into four geographic remoteness categories (see Box) using the Accessibility/Remoteness Index of Australia (ARIA).4 Within each ARIA category, we grouped SLAs into tertiles of socioeconomic disadvantage based on their Australian Bureau of Statistics’ Socio-Economic Indexes for Areas (SEIFA) score. We then compared the average rates of GP use between tertiles for the 2-year period 1996–1997. Our analysis included a measure of the number of full-time equivalent (FTE) GPs per 10 000 population in each SLA as a test of equity: similar or higher rates of GP use in disadvantaged SLAs independent of GP availability suggest equity of access.

In areas classified as “highly accessible”, rates of GP use were significantly (10%) higher in disadvantaged SLAs after adjusting for GP availability (Box). The reverse was found in “remote/very remote” areas, where rates of GP use were about 36% lower in disadvantaged SLAs. Also, the strength of the relationship between GP availability and GP use differed across the ARIA categories. In “highly accessible” areas, a unit increase in the number of FTE GPs per 10 000 population was associated with a 1% increase in GP use, whereas in “remote/very remote” areas it was associated with a 15% increase (data not shown). This suggests that disadvantaged groups in rural and remote areas experience disproportionate difficulty accessing GP services. These areas are underserved by GPs, who charge more for their services and are less likely to bulk-bill.5

It seems that in metropolitan regions the Medicare principle of equity of access to GP services is being realised (ie, people with higher levels of morbidity are making greater use of GP services), whereas in remote and very remote areas this is not the case. The findings might also reflect the fact that disadvantaged groups (especially in rural and remote areas) make greater use of emergency departments of local hospitals or other community-based or primary care outreach services — these services are not covered by Medicare and, therefore, are not taken into account in the rates of GP use presented here.

Association between socioeconomic disadvantage and use of general practitioners within ARIA* categories†

* ARIA (Accessibility/Remoteness Index of Australia) categories:4

• Highly accessible: areas with relatively unrestricted access to a wide range of goods and services and opportunities for social interaction.

• Accessible: areas with some restrictions to accessibility of some goods, services and opportunities for social interaction.

• Moderately accessible: areas with significantly restricted accessibility of goods, services and opportunities for social interaction.

• Remote/very remote: areas with very restricted or very little accessibility of goods, services and opportunities for social interaction.

† Relationship between area disadvantage and GP use is adjusted for number of full-time equivalent GPs per 10 000 population.

‡ Each tertile comprises approximately a third of the statistical local areas (SLAs) in the six Australian states. The high and low tertiles comprise the 33% least and most socioeconomically disadvantaged SLAs, respectively.