The economic benefits of eliminating Indigenous health inequality in the Northern Territory

Zhao and colleagues1 quantified the burden of indigenous health inequality in Australia’s Northern Territory. Any physician who has worked in the NT would agree, although the quantum calculated may shock readers.

However, Zhao and colleagues appear to have left out an epidemiological principle in presenting their analysis: stratify appropriately, or risk unbeknown confounding.

The authors have not taken into consideration the differences between the regions where Indigenous Australians live. The detrimental causes affecting Indigenous populations in the NT are more intense there than among Indigenous people on Australia’s eastern coast, for example, and increase as one moves away from Darwin to remote areas, across the whole spectrum of causes of inequality. Gray and colleagues,2 cited in the article, list many of the causes of Indigenous health inequality, including “lower levels of education, training and skill levels, … living in areas with fewer labour market opportunities, higher levels of … interactions with the criminal justice system, … and lower levels of job retention”. Employment, or lack of it, integrates and acts as a proxy measure of effect for many of these causes. If Zhao and colleagues had considered this variability of effect, they might have realised that the statement that “between 1994 and 2008, Indigenous employment in Australia increased by 55–70%” is misleading.

If Australia is to close the gap between its Indigenous and non-Indigenous people, the government needs to recognise this spectrum of effect across the continent.