Collection of mortality data

Registration of death has been compulsory in Australia since the mid-1850s with deaths registered by the Registrars of Births, Deaths and Marriages in each State and Territory. Since 1906 the The Bureau of Census and Statistics (Commonwealth Statistician) has compiled the information collected by the Registrars and published national death statistics. In addition, State-specific statistics have been published by the State Statisticians.

Information about a death is recorded on a death certificate and includes the underlying cause of death (the disease or condition leading directly to death) and a listing of other conditions contributing to that death.

Death certification can be completed in three ways:

1. If a medical practitioner had treated the deceased recently and the medical practitioner was certain of the cause of death, then the medical practitioner can provide the required certificate.
2. If no medical practitioner can certify the cause of death (e.g. unexplained deaths), then the case is referred to the government pathologist to conduct an autopsy to determine the cause of death.
3. In a number of cases referred to the government pathologist, the Coroner determines the cause of death (e.g. many deaths resulting from accidents are referred to the Coroner).

The information collected in a death certificate has been standardised to a large degree and guidance for completion of death certificates is set out in Cause of Death Certification Australia produced by the Australian Bureau of Statistics (ABS 1997b).

Additional demographic and administrative information is collected by the funeral directors, usually through the next of kin, or a person known to the deceased.

The death certificate and accompanying demographic and administrative information is then registered with the Registrar of Births, Deaths and Marriages who in turn pass the data to the Australian Bureau of Statistics for the compilation of national death statistics.

As with any data collection, there are problems with data quality which change over time. Changing diagnostic practices and medical understanding of disease processes impact on the coding of cause of death over time and can lead to misclassification in causes of death statistics. For instance, HIV/AIDS was introduced as a cause of death code in 1988. It is believed that not all HIV/AIDS deaths were initially coded to HIV/AIDS due to it being a relatively new disease (although this has presumably become less of a problem as time has gone on) and also because of the social stigma associated with the disease.

A key data quality issue in the mortality database is the identification of Indigenous peoples. Prior to 1980 Indigenous deaths were not routinely identified in mortality data. After 1980 difficulties were encountered due to a lack of standards in identification procedures, however since 1998 national standards have been introduced. While there have been significant efforts to improve Indigenous health data, mortality data for Indigenous peoples is patchy in its quality, coverage and completeness. Care should be taken in using these data and guidance should be sought from the mortality team or publications such as The health and welfare of Australia's Aboriginal and Torres Strait Islander peoples 2008.