Web update: Incidence of selected cancers in 2009–2013 - Technical Note - Incidence of selected cancers in 2009–2013

Web update: Incidence of selected cancers in 2009–2013

Incidence of selected cancers in 2009–2013

Web update: Incidence of selected cancers in 2009–2013 presents statistics about local cancer incidence rates. Information is available for all cancers combined, as well as the following cancers; breast, cervical, prostate, colorectal, lung and melanoma of the skin. Results are presented for the 31 Primary Health Network (PHN) areas that cover Australia and for more than 300 smaller local areas called Statistical Areas Level 3 (SA3s), as defined by the Australian Bureau of Statistics (ABS).

This technical note summarises indicator specifications and methods used to calculate results presented in the Web update: Incidence of selected cancers in 2009–2013.

The Australian Cancer Database

Data for the web update were sourced from the Australian Cancer Database (ACD), compiled by the Australian Institute of Health and Welfare (AIHW). Incidence data are presented for 2009 to 2013 because at the time of creation, 2013 was the most recent year for which actual data were available for all states and territories.

All Australian states and territories have legislation that makes cancer a notifiable disease (with the exception of basal and squamous cell carcinomas of the skin (BCCs and SCCs)). Various institutions such as hospitals, pathology laboratories and registries of births, deaths and marriages must report cancer cases and deaths to their jurisdictional cancer registry. Each registry supplies cancer incidence data annually to the AIHW under an agreement between the registries and the AIHW. These data are checked, standardised and compiled into the ACD, the only repository of national cancer incidence data.

The ACD records all primary cancers, except for BCCs and SCCs which are not collected by the state and territory cancer registries. For more information, see the latest Data quality statement for the ACD, available online at http://meteor.aihw.gov.au/content/index.phtml/itemId/687104.External link, opens in a new window.[http://meteor.aihw.gov.au/content/index.phtml/itemId/687104]

About the measure

The measure used to describe cancer incidence is outlined in the indicator specifications. The incidence data refer to the number of new cases diagnosed in 2009–2013, rather than the number of people newly diagnosed (because one person can be diagnosed with more than one cancer in a year), though the numbers are likely to be similar. The new cases in this incidence data include only primary cases (i.e. a tumour that is at the site where it was first formed, rather than a metastasis/ secondary cancer).

About the method

Age-standardisation

The web update includes measures expressed as age-standardised rates per 100,000 population. Age-standardised rates are hypothetical rates that would have been observed if the populations studied had the same age distribution as the standard population.

The direct method of age-standardisation was applied to the data. Age-standardised rates were derived by calculating crude rates by five year age groupings of 0–4 years to 85+ years. These crude rates were then given a weight that reflected the age composition of the standard population. The current standard population is the ABS Estimated Resident Population for Australia as at 30 June 2001. The method for calculating age-standardised rates for Primary Health Network areas and Statistical Areas Level 3 was the same.1

Presentation of results

Geography

The web update presents information at the geography of:

  • Primary Health Network (PHN) areas – 31 geographic areas covering Australia, with boundaries defined by the Australian Government Department of Health
  • Statistical Areas Level 3 (SA3s) – 333 geographic areas covering Australia, with boundaries defined by the ABS.2

National incidence rates for each of the selected cancers are also included for context.

Cancer incidence rates at PHN area and SA3 level were compiled by applying a geographic concordance to the ACD unit record data. The concordance used the Statistical Area Level 2 (SA2) of the residential address as recorded on the ACD.

Where an SA2 boundary overlapped a PHN area, records were attributed to a PHN area on the percentage of the population within that SA2 that fell within each PHN area. Figures were rounded at the end of the calculations to avoid truncation error.

  1. AIHW (Australian Institute of Health and Welfare) 2005. Age-standardised rate. Canberra: AIHW. Viewed 8 March 2017, http://meteor.aihw.gov.au/content/index.phtml/itemId/327276External link, opens in a new window..
  2. ABS (Australian Bureau of Statistics) 2011. Australian Standard Geographical Classification (ASGC). Canberra: ABS. Viewed 3 March 2017, http://www.abs.gov.au/websitedbs/D3310114.nsf/home/Australian+Statistical+Geography+Standard+(ASGS)External link, opens in a new window..
  3. WHO (World Health Organization) 1992. International Statistical Classification of Diseases and Related Health Problems. 10th revision, volumes 1 and 2. Geneva: WHO.