What explains the regional variation in the use of general practitioners in Australia?

Abstract

Background: Regional variation in the use of health care services is widespread. Identifying and understanding the sources of variation and how much variation is unexplained can inform policy interventions to improve the efficiency and equity of health care delivery. Methods: We examined the regional variation in the use of general practitioners (GPs) using data from the Social Health Atlas of Australia by Statistical Local Area (SLAs). 756 SLAs were included in the analysis. The outcome variable of GP visits per capita by SLAs was regressed on a series of demand-side factors measuring population health status and demographic characteristics and supply-side factors measuring access to physicians. Each group of variables was entered into the model sequentially to assess their explanatory share on regional differences in GP usage. Results: Both demand-side and supply-side factors were found to influence the frequency of GP visits. Specifically, areas in urban regions, areas with a higher percentage of the population who are obese, who have profound or severe disability, and who hold concession cards, and areas with a smaller percentage of the population who reported difficulty in accessing services have higher GP usage. The availability of more GPs led to higher use of GP services while the supply of more specialists reduced use. 30.56% of the variation was explained by medical need. Together, both need-related and supply-side variables accounted for 32.24% of the regional differences as measured by the standard deviation of adjusted GP-consultation rate. Conclusions: There was substantial variation in GP use across Australian regions with only a small proportion of them being explained by population health needs, indicating a high level of unexplained clinical variation. Supply factors did not add a lot to the explanatory power. There was a lot of variation that was not attributable to the factors we could observe. This could be due to more subtle aspects of population need or preferences and therefore warranted. However, it could be due to practice patterns or other aspects of supply and be unexplained. Future work should try to explain the remaining unexplained variation.

An assessment of the spatial distribution of bulk billing-only GP services in Australia in relation to area-based socio-economic status

“…Findings highlight the many lower socio-economic regions in Australia with a lack of affordable services. Several authors have reported differences in Australian GP distribution, utilisation and GP employment locality choices within lower SES area levels (Roeger et al 2010;McRae and Butler 2014;Lyle and Hendrie 2019;McIsaac et al 2019;Mu and Hall 2020). In contrast, a study published two decades ago documented high GP hours per population and higher bulk billing rates in the most disadvantaged areas in compari-Fig.…”

“…Business sustainability and market forces greatly impact the viability of bulk billing-only practices and billing models (Royal Australian College of General Practitioners 2018). There are few studies examining bulk billing practices and of these few, bulk billing behaviour is suggested to be influenced by regional area status, practice size, consultation length, patient income and practice location (Britt et al 2004;Achat et al 2010;De Abreu Lourenco et al 2015;Mu and Hall 2020;O'Sullivan et al 2022).…”

“…The spatial distribution of healthcare services is a measurable component of access, simplified as ratios of supply (services) and demand (population) (Roeger et al 2010). Comparative trends in population characteristics, such as socio-demographic and economic status, can be observed in the variances of the supply and demand of healthcare services (Roeger et al 2010;Dudko et al 2018;Lyle and Hendrie 2019;Mu and Hall 2020;Pulok et al 2020a). Previous research has indicated that these geographical disparities in distribution and supply of healthcare services have a negative impact on health outcomes (Butler et al 2010;Ireland et al 2017;Turner et al 2017).…”

“…Previous research has indicated that these geographical disparities in distribution and supply of healthcare services have a negative impact on health outcomes (Butler et al 2010;Ireland et al 2017;Turner et al 2017). Leading drivers of variations in general practitioner (GP) services are both supplier-induced or population needs-based (McRae and Butler 2014;Mu and Hall 2020). For example, differences in utilisation and demand for health care along with GP labour and market-forces attribute to underserved or overserved areas (McIsaac et al 2019;Mu and Hall 2020).…”

“…Leading drivers of variations in general practitioner (GP) services are both supplier-induced or population needs-based (McRae and Butler 2014;Mu and Hall 2020). For example, differences in utilisation and demand for health care along with GP labour and market-forces attribute to underserved or overserved areas (McIsaac et al 2019;Mu and Hall 2020). The inverse care law proposed by Tudor Hart further illustrates this concept where the 'availability of good medical services tends to vary inversely with the need for it in the population served ' (Tudor Hart 1971, p.…”