The AIHW manages and uses deaths data for monitoring and surveillance of deaths at the population level and for data linkage in health and medical research. All data linkage work at AIHW requires approval by the AIHW Ethics Committee.

How are deaths registered?

In Australia, either a medical practitioner or a coroner is required to certify the cause of death. They should report on all medical conditions that directly caused or contributed to the death and, where appropriate, the circumstances (for example, the type of accident or violence) that led to the death. Important demographic information, such as the sex of the person and their age at death, is also reported.

All deaths are registered with the Registrars of Births, Deaths and Marriages in each state and territory and additional information about coroner-certified deaths are maintained by the National Coronial Information System. Demographic and other important information about the deceased person is captured on a deaths registration statement.

Roles and responsibilities of agencies that contribute to the development of national cause of death data in Australia

The Registrars of Births, Deaths and Marriages (RBDMs) in each jurisdiction are responsible for maintaining registers of deaths. Individual state and territory legislation governs the registration process and the roles and responsibilities of the registries.

The National Coronial Information System (NCIS) is a data storage, retrieval, analysis, interpretation and dissemination system for coronial information. It enables coroners, their staff, public sector agencies, researchers and other agencies to access coronial data to inform death and injury prevention activities. It contains data about deaths reported to an Australian coroner from July 2000 (from 1 January 2007 for Queensland), and to a New Zealand coroner from July 2007 (closed cases only), and is an initiative of the Australasian Coroners Society. The NCIS is managed by the Victorian Department of Justice on behalf of a Board of Management, and is based at the Coronial Services Centre in Southbank, Victoria.

The Australian Bureau of Statistics (ABS) is Australia’s national statistical agency. The ABS provides key statistics on a wide range of economic, environmental and social issues. This includes information about the Australian population for which deaths information is required. The ABS also codes the causes of deaths to an international standard making the data useable for statistical purposes. The ABS sources information about the circumstances of the death for coroner-certified deaths from the NCIS. This information facilitates coding of the cause of death. In addition to coding causes of death, the ABS enhances the statistical utility of the data by coding various sociodemographic items such as area of usual residence and country of birth.

The Australian Coordinating Registry (ACR) is an agency appointed for managing a particular activity on behalf of the all RBDMs. A coordinating registry undertakes the coordination and management of the designated activity. The underlying legal responsibility is retained by the collective Registrars.

How are causes of death coded?

The ABS sources information about deaths and their causes from the RBDMs in each state and territory. The ABS compiles these data and codes the causes of death to an international standard, called the International Statistical Classification of Diseases and Related Health Problems (ICD). Coding causes of death to an international standard enables the comparability of statistics over time and between countries.

The ICD is revised periodically and currently in its tenth revision (ICD-10). The ICD-10 has been used for Australian causes of death statistics since 1997 and comprises more than 14,000 causes of death and illness; analysis of groups of causes is therefore more manageable than individual causes.

The coding produces an underlying cause—the disease or condition which initiated the sequence of events resulting in death—and, for most deaths, associated causes (any other diseases or conditions that contributed to the death but were not the underlying cause).

Once coded, causes of death can be categorised into disease groupings. Disease groupings are useful for tabulating causes of death in a meaningful way and for examining patterns and trends by cause of death and other important population attributes.

A common method of grouping causes is by ICD chapters (see Table 1). The chapters are arranged according to the type of disease (for example, ‘Certain infectious or parasitic diseases’), the body system affected (for example, ‘Diseases of the circulatory system’) or the circumstance causing death (for example, ‘External causes of morbidity and mortality’, which include injury and poisoning).

For some public health purposes, information about causes of death needs to be more specific; coding causes of death enables identification of specific causes such as influenza, stroke or motor vehicle accident.

There are other methods of grouping diseases that are useful for public health purposes. For example, see Classifying causes of death.

Table 1: International Statistical Classification of Diseases and Related Health Problems 10th revision (ICD-10) chapters

ICD-10 codes Chapter name
A00–B99 Certain infectious and parasitic diseases
C00–D48 Neoplasms
D50–D89 All diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism
E00–E90 Endocrine, nutritional and metabolic diseases
F00–F99 Mental and behavioural disorders
G00–G99 Diseases of the nervous system
H00–H59 Diseases of the eye and adnexa
H60–H95 Diseases of ear and mastoid process
I00–I99 Diseases of the circulatory system
J00–J99 Diseases of the respiratory system
K00–K93 Diseases of the digestive system
L00–L99 Diseases of the skin and subcutaneous tissue
M00–M99 Diseases of the musculoskeletal system and connective tissue
N00–N99 Diseases of the genitourinary system
O00–O99 Pregnancy, childbirth and the puerperium
P00–P96 Certain conditions originating in the perinatal period
Q00–Q99 Congenital malformations, deformations and chromosomal abnormalities
R00–R99 Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified
S00–T98 Injury, poisoning and certain other consequences of external causes
V01–Y98 External causes of morbidity and mortality
Z00–Z99 Factors influencing health status and contact with health services

When are deaths data updated?

Deaths data and information about causes of death are compiled by the ABS. Newer information becomes available to the AIHW after the ABS releases their summaries of causes of death for each year.

The AIHW applies to access these data via the ACR.

Another factor related to the timeliness of deaths data is the processing cycle and revisions to the causes of death. Data are processed according to a reference year; all deaths that are received by the ABS for a reference year and within a specified time period are captured and counted for that reference year. Once the deaths for the reference year are compiled to represent a year of registration, the deaths are coded with an underlying cause of death and associated causes of death where applicable.

The first release of the coded causes of death is referred to as the ‘preliminary’ version. In this version, deaths that were reported to the coroner but remain as an open case usually have a non-specific cause (unknown) cause of death.

Following the release of the preliminary cause of death data, the cause of death for coroner-certified deaths are revised to ascertain a more specific cause of death for any subsequently closed coroner cases. This revision results in a ‘revised’ version of the cause of death data.

The same process occurs again to produce a ‘final’ version of cause of death data.

Aspects of these processes that can influence the accuracy and timeliness of data are that:

  • Only coroner-certified deaths are subject to revision. Deaths are reported to a coroner under the following circumstances (which varies by jurisdiction):
    • the death is unexpected and the cause is unknown;
    • the person died in an unnatural or violent manner;
    • the death occurred during or as a result of an anaesthetic;
    • the death occurred to a person being ‘held in care’ or custody immediately before they died; or
    • the identity of the person is unknown.
  • Coronial investigations can take several months or even years to complete. The length of time required for the coronial process to be finalised and the coroner case closed will depend on the unique circumstances around each case and may vary by jurisdiction. The completeness and quality of deaths data are affected by the volume of coroners' cases which have not yet been closed or for which there is insufficient information for the ABS to apply a specific cause of death code.
  • The latest year of cause of death data available are always the preliminary version; by the time that the revised data for that year become available, preliminary deaths for the subsequent year are available. Consequently, tabulations using the latest year of cause of death data available will always reflect the preliminary cause of death codes.

Figure 1: Scope and release timeline of Cause of Death Unit Record Files (CODURF) for deaths registered in 2012

  • Scope: Deaths occurring in 2012 that are registered with the RBDMs and received by the ABS by end March 2013; includes previously unregistered deaths that may have occurred before 2012.
  • Release: May 2014 (deaths, i.e. counts released in November 2013).
  • Revisions: Coroner-certified deaths have preliminary cause of death codes and are subject to further revision.
  • Scope: As above; there are no changes to the overall number of deaths in this file.
  • Release: July 2015.
  • Revisions: All coroner-certified deaths that have been closed since the preliminary version are updated using newer information about the causes of death. Coroner-certified deaths have revised cause of death codes and are subject to further revision.
  • Scope: As above; there are no changes to the number of deaths in this file.
  • Release: July 2016.
  • Revisions: All coroner-certified deaths that have been closed since the revised version are updated using newer information about the causes of death. Coroner-certified deaths have final cause of death codes and are no longer subject to revision.

For a more detailed description of the coverage and processing of deaths data, including deaths certified by the coroner, refer to the Explanatory Notes in ABS Causes of death, Australia (ABS Catalogue No. 3303.0), which is available from the ABS website.