Technical notes
- Cancer is classified by the International Statistical Classification of Diseases and Related Health Problems Version 10 (ICD–10). This is a statistical classification, published by the World Health Organization, in which each morbid condition is assigned a unique code according to established criteria.
- Actual mortality data, from the National Mortality Database, up to 2021 are based on the year of occurrence of the death and data for 2022 are based on the year of registration of the death.
- For most cancers, the 2021–2024 incidence estimates are projections based on 2011–2020 incidence data. For cancers where COVID-19 may have led to lower cancer incidence in 2020 and it was likely the reduction may influence the reliability of projections, the 2021–2024 incidence estimates are based on 2010–2019 incidence data (these cancers are breast cancer, melanoma of the skin, colorectal cancer, colon cancer, rectosigmoid junction cancer, rectal cancer, appendiceal cancer, retroperitoneal and peritoneal cancer and thyroid cancer). Prostate cancer uses the 2019 age-specific rates and keeps these constant for projections. While normally the most recent actual year of data would be used to inform prostate cancer projections, prostate cancer incidence in 2020 may have been impacted by COVID-19 and 2019 was used in preference. For more information about prostate cancer projections, please read Cancer data commentary 9.
- The 2023–2024 mortality estimates from the National Mortality Database are projections based on 2013-2022 data. Mortality estimates from the Australian Cancer Database for 2021-2024 are based on 2011-2020 data.
- Projection methods rely on the assumption that past trends may be reasonably used to estimate future counts and rates. For prostate cancer incidence, this has generally not been the case in more recent years. Prostate cancer incidence use current age specific rates, and not cancer trend data, applied to population estimates.
- Relative survival was calculated with the period method, using the period 2016–2020 (Brenner & Gefeller 1996). This captured the survival experience of people who were diagnosed with cancer before or during 2016–2020 and were still alive at the beginning of 2016. Data from the National Death Index (NDI) on deaths (from any cause) that occurred up to 31 December 2020 were used to determine which people with cancer had died and when this occurred.
- Relative survival for registry-derived (RD) stage tables was calculated using the cohort method, using the period 2011–2016. In this method, a cohort of patients diagnosed with cancer is followed over time to estimate the proportion surviving for a selected timeframe (e.g. 5 years).
- Age-specific incidence and mortality rates are expressed as per 100,000 population.
- Age-standardised incidence and mortality rates for the Australian population were age standardised to the 2001 Australian Standard Population and a separate series are available and standardised to the 2024 Australian population; rates are expressed per 100,000 population.
- Incidence and mortality rates are based on the Australian population as at 30 June. Prevalence rates are based on the Australian population as at 31 December.
- Stage data for colorectal cancer excludes cases identified from death certificates only, cancer of the appendix (ICD-10 code C18.1), and colorectal cancers with a histology for which staging rules are not applicable.
- Stage data for breast cancer in females includes ICD-10 code C50, lung cancer excludes trachea (C34), melanoma of the skin excludes skin of genitals and melanoma of “unknown primary site” (C43) and prostate cancer includes C61. Certain morphology codes are excluded.
Brenner H and Gefeller O 1996. An alternative approach to monitoring cancer patient survival. Cancer78:2004–10.