Oral Presentation Australian Epidemiology Association ASM 2018

Quantifying inequalities in mortality in Australia: insights from linking Census with mortality data (#6)

Rosemary Korda 1 , Nicholas Biddle 1 , John Lynch 2 , Emily Banks 1 , James Eynstone-Hinkens 3 , Naomi Priest 1 , Kay Soga 1 , Tony Blakely 4
  1. Australian National University, Acton, ACT, Australia
  2. The University of Adelaide, Adelaide, SA, Australia
  3. Australian Bureau of Statistics, Canberra, ACT, Australia
  4. Otago University, Otago, New Zealand

Background

Addressing inequalities in mortality is a key public health issue, requiring accurate quantification and monitoring. Our ability to do this in Australia has to date been limited by the available data.  The Australian Bureau of Statistics has recently created a new resource by linking Death Registrations data to the Census, enabling quantification of mortality by individual-level socioeconomic measures.

Methods

We present the first analysis of linked Deaths Registrations to Census data, containing deaths within 13 months of the 2011 Census date, linked probabilistically to 2011 Census data.  We used negative binomial regression to quantify inequalities in relation to education, weighted to adjust for linkage bias. We compared these inequality estimates with those from area-based measures.

Results

Men with no educational qualifications had age-adjusted mortality rates 1.84 (95% CI: 1.75‒1.93) times those of men with a bachelor degree or higher, among women the corresponding relative rate (RR) was 1.45 (1.38‒1.53). For younger people (aged 25-44), these inequalities were substantially higher (men: RR=3.69 [3.16‒4.31]; women: 2.36 [1.97‒2.82]). Total excess deaths associated with less than bachelor education was around 26,000. Socioeconomic gradients in education remained apparent among individuals within each area-SEP quintile, highlighting the socioeconomic variation among individuals within these area-based socioeconomic groups. 

Conclusion/Implications

The newly-created linked Deaths Registrations to Census data file, accessible through the virtual ABS Datalab, is a rich resource for generating evidence, including on the contributions of a large range of social and demographic characteristics to variation in mortality. We show area-based measured are inadequate for capturing inequality.