Age is calculated as at 30 June of the collection year.
Agency remoteness area
Dosing points have been classified according to their remoteness area (RA) as defined by the Australian Statistical Geography Standard (ASGS) Remoteness Structure . This structure allows areas that share common characteristics of remoteness to be classified into broad geographic regions of Australia. These areas are:
- Major cities
- Inner regional
- Outer regional
- Very remote.
The Remoteness Structure divides each state and territory into several regions on the basis of their relative access to services.
Examples of places that are considered Major cities in the ASGS classification include Sydney, Canberra and Newcastle. Hobart and Bendigo are Inner regional areas and Cairns and Darwin are Outer regional areas. Katherine and Mount Isa are Remote areas and Tennant Creek and Meekatharra are Very remote.
Using this classification, dosing points were assigned to an RA based on their recorded Statistical Areas Level 2 (SA2) code.
Some SAs are split between multiple remoteness areas. Where this was the case, the data were weighted according to the proportion of the population of the SA2 in each remoteness area.
Average annual rates of change
The average annual rates of change or growth rates have been calculated as geometric rates:
Average rate of change = ((Pn/Po)^(1/n) -1) x 100
Pn= value in the later time period
Po= value in the earlier time period
n = number of years between the 2 time periods.
Population estimates used for rates calculations
All rates in this report, including historical rates, have been calculated using population estimates based on the 2011 Census. All Indigenous rates in this report are calculated using the Indigenous population estimates and projections, based on the 2011 Census.
Crude rates are calculated using the Australian Bureau of Statistics estimated resident population (ERP) as at 30 June of each collection year. Rates for 2017 data were calculated using the preliminary ERP at 30 June 2017, with the exception of remoteness rates which were calculated using the preliminary ERP at 30 June 2016.
Trend data may differ from data published in previous versions of National opioid statistics in Australia due to data revisions.