All information about geographical areas for the Atlas were sourced from the Australian Bureau of Statistics (ABS).
Statistical Area Level 2 (SA2)
Statistical Areas Level 2 (SA2) are the smallest areas that have annual estimated resident population data readily available. The ABS defines their purpose to “represent a community that interacts together socially and economically.”
The Atlas uses the Australian Statistical Geography Standard (ASGS) July 2011 edition for SA2 boundaries. There are 2,214 SA2s defined for Australia, but some of these (n=18) are undefined categories which have no location. This leaves 2,196 SA2s that represent physical geographical areas. Of these, we excluded 28 SA2s that had no population and a further 17 that had fewer than 5 residents on average per year during 2010-2014. Finally, we also excluded the very remote islands of Christmas Island, Cocos Island and Lord Howe Island from the analyses. This means the Australian Cancer Atlas provides modelled estimates for 2,148 SA2s across Australia.
The SA2 geographical areas can be used as building blocks to form larger geographical regions. The larger regions used in the Australian Cancer Atlas include States and Territories, Greater Capital City Regions, remoteness categories, and categories of area-level socioeconomic status. Rather than providing one summary estimate for these broader regions, the Atlas reports on the range of SA2-specific estimates within each broad region.
States and territories
There are eight Australian states and territories: New South Wales, Victoria, Queensland, South Australia, Western Australia, Tasmania, Northern Territory, Australian Capital Territory. For the purposes of this Atlas, Jervis Bay is considered to be part of New South Wales.
Greater capital city regions
The greater capital city regions comprise Sydney, Melbourne, Brisbane, Adelaide, Perth, Hobart, Darwin and Canberra. The geographical boundaries of these greater capital city areas are defined by the Australian Bureau of Statistics. (ASGS – Vol.1 Main structure and Greater Capital City Statistical Areas, July 2011)
The Australian Bureau of Statistics produce Remoteness Areas, which divide small areas in Australia into five categories of remoteness based on their relative access to services. These remoteness areas are measured using the Accessibility and Remoteness Index of Australia (ARIA+) developed by the University of Adelaide. The ARIA+ is a purely geographic measure of remoteness, and considers services within the specific area, and the distances to localities with more comprehensive services. These measures were originally defined for SA1s, meaning that when aggregated to form SA2s, some SA2s had multiple remoteness categories. For these SA2s, we assigned one remoteness category based on population proportions.
There are five categories of Remoteness – Major city, Inner regional, Outer regional, Remote and Very remote.
The area-based socioeconomic groupings were categorised using the Socioeconomic Indexes For Areas (SEIFA), which have been developed by the Australian Bureau of Statistics. Note that these indices reflect the average characteristics of people living in the area, so may not reflect the socioeconomic status of all individuals living in that area.
There are five different SEIFA measures; however the Index of Relative Socio-economic Advantage and Disadvantage (IRSAD) has been used for the Atlas. The IRSAD summarises information about the economic and social conditions of people and households within an area, including details about household income, education levels, occupation categories and car ownership.
Each SA2 is allocated an IRSAD score, and then ranked from highest to lowest across Australia. These ranked SA2s were then grouped into five groups (called quintiles), weighted by the population so that about 20% of the population are in each IRSAD quintile. The five quintiles are labelled Most advantaged, Advantaged, Middle, Disadvantaged and Most disadvantaged.