The contemporary demography of indigenous Australians

A review of life expectancy and infant mortality estimations for Australian Aboriginal people

Background

Significant variation exists in published Aboriginal mortality and life expectancy (LE) estimates due to differing and evolving methodologies required to correct for inadequate recording of Aboriginality in death data, under-counting of Aboriginal people in population censuses, and unexplained growth in the Aboriginal population attributed to changes in the propensity of individuals to identify as Aboriginal at population censuses.

The objective of this paper is to analyse variation in reported Australian Aboriginal mortality in terms of LE and infant mortality rates (IMR), compared with all Australians.

Methods

Published data for Aboriginal LE and IMR were obtained and analysed for data quality and method of estimation. Trends in reported LE and IMR estimates were assessed and compared with those in the entire Australian population.

Results

LE estimates derived from different methodologies vary by as much as 7.2 years for the same comparison period. Indirect methods for estimating Aboriginal LE have produced LE estimates sensitive to small changes in underlying assumptions, some of which are subject to circular reasoning. Most indirect methods appear to under-estimate Aboriginal LE. Estimated LE gaps between Aboriginal people and the overall Australian population have varied between 11 and 20 years.

Latest mortality estimates, based on linking census and death data, are likely to over-estimate Aboriginal LE.

Temporal LE changes by each methodology indicate that Aboriginal LE has improved at rates similar to the Australian population overall. Consequently the gap in LE between Aboriginal people and the total Australian population appears to be unchanged since the early 1980s, and at the end of the first decade of the 21st century remains at least 11–12 years.

In contrast, focussing on the 1990–2010 period Aboriginal IMR declined steeply over 2001–08, from more than 12 to around 8 deaths per 1,000 live births, the same level as Australia overall in 1993–95. The IMR gap between Aboriginal people and the total Australian population, while still unacceptable, has declined considerably, from over 8 before 2000 to around 4 per 1,000 live births by 2008.

Conclusions

Regardless of estimation method used, mortality and LE gaps between Aboriginal and non-Aboriginal people are substantial, but remain difficult to estimate accurately.

Northern Territory indigenous life expectancy improvements, 1967-2004

OBJECTIVE

To assess the extent of changes in life expectancy at birth for the Indigenous population of the Northern Territory (NT) over the period 1967-2004, and to determine which age-specific mortality rates were mostly responsible for such change.

METHODS

Life expectancy at birth figures were obtained via life table calculations using a high-quality and internally consistent dataset of NT Indigenous deaths and populations covering the period 1967-2004. A life expectancy at birth age decomposition technique was then applied.

RESULTS

Indigenous life expectancy at birth has risen considerably in the NT, increasing from about 52 years for males and 54 years females in the late 1960s to about 60 years for males and 68 years for females in recent years. Significantly, for NT Indigenous females the gap with total Australian life expectancy has narrowed.

CONCLUSIONS

In contrast to popular perception, Indigenous life expectancy in the Northern Territory has improved substantially from the late 1960s to the present.

IMPLICATIONS

The widespread pessimism that surrounds Indigenous health and mortality is largely unfounded, at least for the NT. Although much remains to be done to reduce Indigenous mortality, the results in this paper demonstrate that improvements are occurring and that sustained and increased effort is worthwhile and will succeed.