Burden of disease analysis produces comparable and concise policy-relevant evidence on the impact of disease, injuries and risks on the population. A key strength of burden of disease is the ability to collate and use data from various sources to develop an internally consistent measure for all diseases. However, as methods used in burden of disease analyses have become increasingly complex over time, the increased complexity makes it much harder to explain the methods, and can result in decreased clarity for stakeholders.

This report describes, as far as practicable, the methods and assumptions used by the Australian Burden of Disease Study (ABDS) 2015 to quantify the fatal and non-fatal effects and causes of diseases and injuries in the Australian population in 2015, 2011 and 2003.

It is a companion publication to Australian Burden of Disease Study: impact and causes of illness and death in Australia 2015 (AIHW 2019a) and Australian Burden of Disease Study: impact and causes of illness and death in Australia 2015—summary report (AIHW 2019b) and was developed to provide transparency of data, assumptions and methods. This report supersedes the methods described in the Australian Burden of Disease Study 2011: Methods and supplementary material (AIHW 2016a) for the national component of the ABDS 2011.

The ABDS 2015 does not estimate the burden of disease and injuries on the Aboriginal and Torres Strait Islander populations as key data sources were not available at the time of analysis.

To make the report easier to read, large tables and additional information are presented in appendices A to G.

Key considerations

The ABDS 2015 methods build on the methodological approach of the ABDS 2011 (AIHW 2014a; AIHW 2016a), along with methodological developments used in recent iterations of the Global Burden of Disease study (GBD 2015 and 2016). Key considerations for the ABDS 2015 were the need for:

  • national estimates which were relevant to Australia, while maintaining comparability with global methods as much as possible
  • sub-national estimates (state/territory, remoteness and socioeconomic group)
  • comparability to 2011 and 2003 estimates to enable valid comparisons over time.

In addition, the following principles were followed to enable improvements and extensions to the methods used in ABDS 2011 (Box 1.1).

Box 1.1: Principles for the ABDS 2015 update

  • If changes were made to the ABDS disease list, methods or model inputs, estimates for previous time points were re-generated to enable true comparison over time.
  • Changes to key inputs (such as disability weights or reference life table) or methods (such as redistribution or comorbidity bias adjustment) must not introduce bias or compromise the consistent and systematic approach for all diseases which is the foundation of the ABDS.
  • Changes to models, model inputs or data sources must:
    • be introduced to improve accuracy and/or defensibility and be evidence-based
    • take into consideration the appropriateness of the change to previous time points.

For example, changes in duration of health loss must consider whether it is appropriate to apply that change to all time points, or only the most recent time point. Changes in duration for more recent time points reflect advances in treatment; ultimately reducing the time spent in ill-health.

  • Variations to the list of diseases/injuries must:
    • comply with criteria developed for selection of diseases and injuries in the ABDS (see Chapter 2)
    • maintain the existing disease list structure
    • maintain mutual exclusivity
    • be consistent with diseases used in the risk factor component.
  • Variations to the risk factors list must:
    • comply with criteria developed for selection of risk factors in the ABDS 
    • be consistent with the disease list (including sequelae) in terms of the associated linked diseases.