Denominator populations

Medicare Benefits Schedule and Pharmaceutical Benefits Scheme denominators

The denominator for the Medicare Benefits Schedule (MBS) and Pharmaceutical Benefits Scheme (PBS) outcomes were derived from the Medicare Consumer Directory (MCD). This was chosen as all persons on the MCD have Medicare access and therefore their services will be recorded in the MBS and PBS datasets. Additionally, the demographic information from MCD enrolments were used for deriving service use and medication use by demographics.

The MCD was limited to people who were alive in 2021. A limitation of using the MCD is we cannot identify people who have left the country prior to 2021. Therefore, the denominator may include people who were not in the country in 2021 and may be larger than the reported estimated residential population (ERP) at that time. This could lead to an underestimate of the service rates due to higher than true denominator. This would be the same for all denominators: the rest of the Australian population, humanitarians and other permanent migrants.

Census 2021 denominator

The denominator used in calculating rates of self-reported long-term health conditions from the census data was all census records which answered the long-term health conditions question (exclude non-responders) and for all migrants who answered the question that linked to a record on SDB.

Deaths denominator

As the deaths data used in this analysis covers the period 2007–2020, a person years denominator was used to provide a way of calculating deaths in the at-risk population over that period.

Person-years was derived in the Australian population from summing the ERP, which provides a measure of the residential population in each year, for the 2007–2020 time period. Person-years was derived in the migrant populations by summing the population in each year from the MCD for the 2007–2020 time period. Migrant population in each year was derived from year of birth, arrival year and year of death information. People with a date of birth prior to the year, who had arrived prior to the year, and had year of death either after the year or not reported were counted in each year. For the rest of the Australian population person-years denominator, the person-years from the MCD were subtracted from the summed ERP values.