Research methods
The method to estimate the prevalence of selected chronic conditions is based on principal or additional diagnosis in public hospital or emergency department (ED) care, or prescription of disease-specific medications (through the PBS/RPBS). The individual diagnosis and medication codes are presented in Classifications and codes.
The focus is chronic conditions that are commonly reported on by AIHW, which can be found at Chronic disease Overview. However, some aggregations were made due to the availability of being able to identify these conditions in the health system data sources.
To estimate the number of people living with chronic conditions, 30 June is selected as the reference date for each year and each person is identified as living with a chronic condition based on diagnosis or dispensed medication in the year before the 30 June reference date. As an example, the prevalence of select musculoskeletal conditions in ex-serving members in June 2020 was 9.2% based on hospital diagnosis or medication dispensing between July 2019 and June 2020. Ex-serving members had to be alive on the reference date to be included within the analysis for that year.
Any health service use prior to becoming an ex-serving member was not used to identify chronic conditions. Persons who only became ex-serving during the year were only identified as having a chronic condition if their health service use after they were ex-serving could be used to identify a chronic condition.