Causes of Death, Australia methodology

This publication contains statistics on causes of death for Australia, together with selected statistics on perinatal deaths.

To complete a death registration, the death must be certified by either a doctor using the Medical Certificate of Cause of Death or by a coroner. In 2023, 87.5% of deaths were certified by a doctor. The remaining 12.5% were certified by a coroner. There are variations between jurisdictions in relation to the proportion of deaths certified by a coroner, ranging from 6.2% of deaths certified by a coroner and registered in Queensland, to 25.6% of deaths certified by a coroner and registered in the Northern Territory.

To complete a perinatal death registration, the death must be certified by either a doctor, using the Medical Certificate of Cause of Perinatal Death or by a coroner. In 2023, 97.4% of perinatal deaths were certified by a doctor, with the remaining 2.6% certified by a coroner. 

It is the role of the coroner to investigate the circumstances surrounding all reportable deaths and to establish, wherever possible, the circumstances surrounding the death, and the cause(s) of death. Although there is variation across jurisdictions in what constitutes a reportable death, they are generally reported in circumstances such as:

• where the person died unexpectedly, and the cause of death is unknown
• where the death resulted, directly or indirectly, from an accident or injury, even if there has been a prolonged interval between the incident and death
• where the person died in a violent or unnatural manner
• where the person died during or as a result of a medical procedure
• where the person was 'held in care' or in custody immediately before they died (noting that ‘in care’ excludes facilities such as residential aged care)
• where a doctor has been unable to sign a death certificate giving the cause of death
• where the identity of the person who has died is unknown.

The registration of deaths is the responsibility of the Australian states and territories Registries of Births, Deaths and Marriages (RBDMs). Deaths occurring in "other territories" of Australia are registered by RBDMs in one of the eight states and territories. The exception to this is deaths occurring on Norfolk Island which are registered by the Norfolk Island Registry of Births, Deaths and Marriages which sits within the Norfolk Island Regional Council. Deaths for "other territories" are included in the death statistics for Australia. 

As part of the registration process, information about the cause of death is supplied by the certifying medical practitioner or by a coroner. Other information about the deceased is supplied by a relative or other person acquainted with the deceased, or by an official of the institution where the death occurred. The information is provided to the Australian Bureau of Statistics (ABS) by individual registries for coding and compilation into the National Mortality dataset. In addition, the ABS supplements this data with information made available via the National Coronial Information System (NCIS). As a voluntary collaboration between the Australian states and territories and New Zealand, the NCIS is independent of the coronial system and does not form any part of the coronial investigation process. The NCIS enables access to some documents produced during the coronial investigation, however it is not intended to be a full replica of the coronial brief.

The diagram below outlines the Australian Causes of Death Statistics System. Each death is certified by either a doctor or coroner and the resultant information is provided to the ABS through the Registrar of Births, Deaths and Marriages in each state or territory and Norfolk Island. Information is also provided via the NCIS for those deaths certified by a coroner. The ABS processes, classifies and validates this information, which is then provided in statistical outputs.

The ABS Causes of Death collection includes all deaths that occurred and were registered in Australia, including deaths of persons whose usual residence was overseas. Deaths of Australian residents that occurred outside Australia may be registered by individual registries but are not included in ABS deaths or causes of death statistics.

The current scope of the statistics includes:

• all deaths being registered for the first time
• deaths in Australia of temporary visitors to Australia
• deaths occurring within Australian Territorial waters
• deaths occurring in Australian Antarctic Territories or other external territories (including Norfolk Island)
• deaths occurring in transit (i.e. on ships or planes) if registered in the Australian state or territory of 'next port of call'
• deaths of Australian Nationals overseas who were employed at Australian legations and consular offices (i.e. deaths of Australian diplomats while overseas) where able to be identified
• deaths that occurred in earlier reference periods that have not been previously registered (late registrations).

The scope of the statistics excludes:

• repatriation of human remains where the death occurred overseas
• deaths of foreign diplomatic staff in Australia (where these can be identified) 
• stillbirths/fetal deaths (these are included in perinatal death statistics (see Perinatal deaths)). In 2007-2009 these were published separately in Perinatal Deaths, Australia, 2009 but are now included in this publication.

Deaths registered on Norfolk Island from 1 July 2016 are included in this publication. This is due to the introduction of the Norfolk Island Legislation Amendment Act 2015. Norfolk Island deaths are included in statistics for "other territories" as well as totals for all of Australia. Deaths registered on Norfolk Island prior to 1 July 2016 were not in scope for death statistics. Prior to 1 July 2016, deaths of people that occurred in Australia with a usual residence of Norfolk Island were included in Australian totals but assigned a usual residence of 'overseas'. With the inclusion of Norfolk Island as a territory of Australia in the Australian Statistical Geography Standard (ASGS) 2016, those deaths which occurred in Australia between January and June 2016 with a usual residence of Norfolk Island were allocated to the Norfolk Island SA2 code instead of the 'overseas' category.

Ideally, for compiling annual time series, the number of deaths should be recorded and reported as those which occurred within a given reference period, such as a calendar year. In Australia, a death cannot be registered until a burial or cremation has occurred. This requirement can result in delays in the registration of a death and in some cases may mean that the registration occurs in subsequent years after the death event. There may also be further delays to the ABS receiving notification of the death from the registries due to processing or data transfer lags. Therefore, every death record will have:

• a date on which the death occurred (the date of occurrence)
• a date on which the death is registered with the state and territory registry (date of registration)
• a date on which the registered death is lodged with the ABS and deemed in scope.

Data can be presented in different ways based on these dates.

Year of registration

From the 2022 issue of the Causes of Death publication data is presented by year of registration (based on date of registration). This represents a change from previous years where data was presented by reference year. This change has been applied across all years to enable consistency of time series for comparable analysis. For some years, the number of deaths registered in that year is the same as the number that fall within scope of the reference year, but for other years, the numbers are quite different.

In recent years, there have been occasions where the ABS has received a large number of deaths which were registered in earlier years. These death registrations fell within scope of the reference year in which they were received. Therefore presenting deaths data by reference year is not necessarily representative of mortality patterns in that year and can have a greater impact on specific causes of death. For examples of where the ABS has received late registrations and the impact on mortality patterns, see Technical Note: Victorian additional registrations and time series adjustment and Technical Note: Victorian additional registrations (2013-2016).

Reference year

Prior to 2022, Causes of Death data was presented by reference year. The scope for reference year includes:

• deaths registered in a reference year (calendar year) and received by the ABS in the reference year
• deaths registered in a reference year (calendar year) and received by the ABS in the first quarter of the subsequent year
• deaths registered in the years prior to a reference year (calendar year) but not received by ABS until the same reference year or the first quarter of the subsequent year, provided that these records have not been included in any statistics from earlier periods.

Data for the ABS Deaths, Australia publication will continue to be presented by reference year. Therefore total numbers of deaths for each year in the Causes of Death publication will not necessarily match total numbers of deaths in the Deaths publication. The table below shows the differences in numbers over the last 10 years.

Year of occurrence

Data can also be presented by year of occurrence (based on date of occurrence). Approximately 5% to 8% of deaths occurring in one year are not registered until the following year or later. 

A small number of tables in the Causes of Death publication are published by year of occurrence, ie. Table 11.21 in the '11. Intentional self-harm (suicide)' data cube; all tables in the '14. Causes of Death by year of occurrence' data cube; and Table 15.25 in the '15. Perinatal deaths' data cube.

Information in the Causes of Death and Deaths publications is not comparable with deaths data published in the monthly Provisional Mortality Statistics reports which provides preliminary counts of deaths by date of occurrence.

Causes of Death data by reference year or year of occurrence is available on request.

This publication draws extensively on information provided freely by the Australian state and territory Registries of Births, Deaths and Marriages, Norfolk Island Regional Council and the Victorian Department of Justice who manage the National Coronial Information System (NCIS). Their continued cooperation is very much appreciated: without it, the wide range of vital statistics published by the ABS would not be available. Information received by the ABS is treated in strict confidence as required by the Census and Statistics Act 1905.

In compiling causes of death statistics, the ABS employs a variety of measures to improve quality, which include editing checks at the individual record and aggregate levels, seeking detailed information from the National Coronial Information System (NCIS), and undertaking a revisions process for open coroner certified deaths. The ABS has also released a revised version of the Cause of Death Certification Guide which provides certifiers with guidance in accurately reporting causes of death on medical certificates.

For coroner certified deaths, the specificity of cause of death coding can be affected by the length of time for the coronial process to be finalised and the coroner case closed. To improve the quality of ICD coding, all coroner certified deaths registered after 1 January 2006 are subject to a revisions process.

Up to and including deaths registered in 2005, ABS Causes of Death processing was finalised at a point in time. At this point, not all coroners' cases had been investigated, the case closed and relevant information loaded into the National Coronial Information System (NCIS). The coronial process can take several years if an inquest is being held or complex investigations are being undertaken. In these instances, the cases remain open on the NCIS and relevant reports may be unavailable. Coroners' cases that have not been closed or had all information made available can impact on data quality as less specific ICD codes often need to be applied.

The revisions process to date has focused on cases that remain open on the NCIS database. ABS coders investigate and use additional information from police reports, toxicology reports, autopsy reports and coroners' findings to assign more specific causes of death. The addition of this information occurs up to 24 months after initial processing and the specificity of the assigned ICD-10 codes increases over time. As time passes after initial processing, many coronial cases are closed, with the coroner having dispensed a cause of death and relevant reports have been made available. This allows ABS coders to assign a more specific cause of death.

These published outputs include 2023 preliminary data, 2022 preliminary revised data and 2021 revised data. For more details of revisions to 2021 and 2022 data refer to the Technical Notes in the 2022 issue of the Causes of Death Methodology. Data for reference years up to and including 2020 are considered final and no longer subject to the standard revisions process. Final data for 2021, revised data for 2022, and preliminary revised data for 2023 will be released in early 2025. 

Excess mortality

While the number of deaths registered in 2023 (183,131) decreased compared with 2022 (by 7,808 or 4.1%), excess mortality remained in 2023. Since the start of the Omicron wave of COVID-19 in Australia (from January 2022), excess mortality has been recorded for all jurisdictions. For more information, including official excess mortality estimates, refer to the article Measuring Australia’s excess mortality during the COVID-19 pandemic until December 2023.

Coroner certified deaths data

Deaths that are referred to a coroner can take time to be fully investigated, which subsequently affects the availability of data to the ABS for cause of death coding. Each year, some coroner cases are coded by the ABS before the coronial proceedings are finalised. Coroner cases that have not been closed or had all information made available can impact on data quality as less specific ICD codes often need to be applied.

Over recent years, for some jurisdictions, there has been an increasing delay in transfer of information between the coroner court and the National Coronial Information Service (NCIS), affecting the availability of autopsy reports, toxicology reports and coronial findings, and updating the closure status. Some jurisdictions are more affected than others. For statistics on case closure and document attachment for each jurisdiction, refer to the Operational Statistics published on the NCIS website.

These delays in the flow of information to the NCIS affect the ABS coding process and are reflected in the dataset by a higher proportion of deaths assigned to ill-defined and unspecified conditions such as Other ill-defined and unspecified causes of mortality (R99), Exposure to unspecified factor (X59) and Unspecified event, undetermined intent (Y34). 

Due to the high number of deaths assigned to these ill-defined and unspecified conditions at preliminary coding, the ABS has implemented an early revision whereby preliminary data is revised during the subsequent causes of death revisions cycle. This early revision has been applied from 2021 onwards and targets open cases coded to Other ill-defined and unspecified causes of mortality (R99), Exposure to unspecified factor (X59) and Unspecified event, undetermined intent (Y34), with the aim of enhancing the specificity of the codes applied to these cases by capturing additional coronial information made available since initial coding. Of deaths in scope for the 2022 revisions period, 660 were able to be assigned to more specific causes of death. For more details of the early revision process refer to Technical Note: Causes of death revisions, 2022 preliminary revision.

Causes of death with a high proportion of coroner certified deaths (e.g., suicide, assault, drug-induced deaths) should be interpreted with caution due to the expectation that this data will change during revisions.

Drug-induced deaths

Drug-induced deaths are those which are directly attributable to drug use. They include deaths due to acute drug toxicity (e.g. overdose) and chronic drug use (e.g. drug-induced cardiac conditions).

On average, 97% of drug-induced deaths are certified by a coroner. There are multiple complex factors which need to be considered when a death is certified as drug-induced. The timing between the death and toxicology testing can influence the levels and types of drugs detected, making it difficult to determine the true level of a drug at the time of death. Individual tolerance levels may also vary considerably depending on multiple factors, including sex, body mass and a person’s previous exposure to a drug. Contextual factors around the death must also be considered such as pre-existing natural disease and reports from informants (e.g., friends and families) regarding the circumstances surrounding death. For these reasons, the certification of a death as being drug-induced can take significant time to complete, making these deaths particularly sensitive to the revisions process. 

Numbers of drug-induced deaths for 2022 and 2023 are influenced by the higher proportion of open cases for these years. It is expected these numbers will increase when the ABS revisions process is applied. Caution should be used when interpreting drug-induced deaths data until numbers are final.

Victorian additional registrations

As a result of two reconciliation exercises conducted jointly between the ABS and the Victorian Registry of Births Deaths and Marriages (Victorian RBDM), additional historical death registrations have been added to the mortality dataset. This was due to an issue associated with the Registry's previous processing system (replaced in 2019) which resulted in some death registrations not being delivered to the ABS in the year they were registered. 

The first exercise (conducted in the first quarter of 2020) resulted in the identification of an additional 2,812 death registrations from 2017 to 2019 that had not previously been provided to the ABS. Of these, 40.4% were registered in 2017, 57.0% in 2018 and the remainder in 2019 (2.6%). The 2,812 Victorian deaths were in scope of the 2019 reference year and therefore included in 2019 counts of total deaths in both the Deaths, Australia, 2019 and Causes of Death, Australia, 2019 datasets.

Of the 2,739 deaths that were registered in 2017 and 2018 and submitted to the ABS for the 2019 reference year 62.9% were certified by a coroner with the remaining 37.1% certified by a doctor. This led to an increase across a number of causes of death, with those more likely to be referred to a coroner (i.e. external causes of death) experiencing larger effects from the delayed delivery of registrations. See Technical note: Victorian additional registrations and time series adjustments in Causes of Death, Australia, 2019 for detailed information on this issue. 

A subsequent exercise (conducted in the first quarter of 2022) identified a further 1,864 death registrations from 2013 to 2016 that had not previously been provided to the ABS. Of these, 31.7% were registered in 2013, 24.6% in 2014, 7.7% in 2015 and the remainder in 2016 (36.1%). As these deaths occurred more than five years prior to the 2021 reference year, they were not considered to be representative of mortality in 2021 and were excluded from the 2021 reference year counts. In the Deaths, Australia publication these additional registrations are included in tables that are presented by year of occurrence of death only. See Technical note: Victorian additional registrations (2013-2016) for more details on these registrations and how they are reflected in published data. 

From the 2022 publication, these additional Victorian registrations obtained by the ABS during both reconciliation exercises are presented by year of registration. This ensures the number of deaths for a particular year is more representative of the deaths that were registered in that year.

Additionally, as part of the implementation of the new registration system in Victoria in February 2019, there was a change in the way coroner referred deaths are reported to the ABS. Previously there was a range of factors that would determine the point at which a coroner referred death was reported to the ABS, often leading to significant delays in reporting. From 2019, this changed and interim registrations (open cases) have been submitted to the ABS resulting in more timely delivery of death registration information to the ABS.

Updates to Western Australian doctor certified causes of death data 2016 to 2020

An issue was identified with cause of death data for doctor certified deaths registered between 2016-2020 in Western Australia. Information originating from Part II of the Medical Certificate of Cause of Death (MCCD) or Medical Certificate of Cause of Perinatal Death (MCCPD) was not uploaded into the ABS Mortality processing system. The main impact was on the associated causes, both in terms of the capture of conditions listed and the number of causes listed as contributing to death. Updated data was released as part of the Revisions to causes of death release and is reflected in this publication. For more detailed information, refer to Technical note: Updates to doctor certified causes of death data, Western Australia, 2016 to 2020.

Updates to Queensland doctor certified causes of death data 2016 to 2021

An issue was identified with cause of death data for doctor certified deaths registered between 2016-2021 in Queensland. Information originally provided to the ABS in Part II of the Medical Certificate of Cause of Death (MCCD) was moved to Part I of the MCCD when uploaded into the ABS Mortality processing system. As a consequence, some cause information did not align with the original certificate and the change in sequence altered the application of the ICD-10 coding rules when assigning the underlying cause of death. This impacted approximately 300 to 600 records each year, representing less than 2% of doctor certified deaths in Queensland. Updated data was released as part of the Revisions to causes of death release and is reflected in this publication.

Change in reporting of Tasmanian birth registrations

Data for Tasmania in 2023 shows an increase of 91 births (1.7%) compared to 2022. This is influenced by a change in scope for the processing of birth registrations from January 2023, which affected births registered in 2022.

Birth registrations are assigned to a reference year based on their date of registration. Up to the 2022 reference year, a legacy reporting issue meant that Tasmanian births were assigned to a reference year based on the date they were first entered into the registry system (the insertion date), rather than the date on which the registration was finalised (the registration date). From the 2023 reference year, the registration date has been used, aligning reporting for all jurisdictions. As the registration date is generally a few days after the insertion date, 334 births that would previously have been recorded with a usual residence of Tasmania in the 2022 reference year now appear in 2023. This change accounted for nearly two-thirds (63.3%) of the decrease in Tasmania's births in 2022. 

All Tasmanian births continue to be registered and reported to the ABS. Detailed births data for 2023 will be released in Births, Australia, 2023.

Impacts of COVID-19 pandemic on birth registrations

In 2020, lockdowns due to the COVID-19 pandemic influenced the number of birth registrations in Australia, with fewer births registered in 2020 compared to recent years. 

In recent years, Victoria has registered a higher proportion of births that occurred in the year prior to registration. This should be considered when comparing year-on-year birth registration counts in Victoria with those observed nationally. The Victorian RBDM have indicated to the ABS they have been working through delayed registrations for 2023 and have registered many of these in 2024. Information on Victorian birth registrations is available online via the Births, Deaths and Marriages Victoria website.

In 2023, Western Australia recorded an increase of 553 registered births (1.8%). Compared to a “typical” year, Western Australia registered a higher proportion of births in 2023 that occurred in 2022 (14.5%). This was related to the clearing of a registration backlog (largely related to the COVID-19 pandemic) in early 2023, for births that occurred in 2022. As such, the recorded increase should be treated with caution as it represents an increase in the number of births registered rather than an actual increase in births that occurred in 2023.

Detailed births data for 2023 will be released in Births, Australia, 2023.

Other historical considerations

In 2018, the Northern Territory Registry of Births, Deaths and Marriages identified a processing issue that led to delays in completing the registration of some births that occurred in previous years. These births have since been registered, resulting in 355 additional births being included in 2018 data, the majority of which (339) were of Aboriginal and Torres Strait Islander children. Care should be taken when interpreting changes in birth counts, infant death rates and fertility rates for the Northern Territory.

In 2016 and 2017 there were lower than expected birth registration counts for New South Wales. The ABS worked with the NSW Registry of Births, Deaths and Marriages (NSW RBDM) to investigate these counts, highlighting that changes to identity requirements in 2016 had prevented some birth registrations from being finalised. The NSW RBDM worked with parents to finalise these registrations, enabling many to be included in 2018 counts. Other initiatives also contributed to the higher count of births in NSW in 2018, including the implementation of an online birth registration system and a campaign aimed at increasing registrations among Aboriginal and Torres Strait Islander parents.

The Census and Statistics Act 1905 provides the authority for the ABS to collect statistical information, and requires that statistical output shall not be published or disseminated in a manner that is likely to enable the identification of a particular person or organisation. This requirement may restrict access to data at a very detailed level.

Some data cells with small values have been randomly assigned to protect confidentiality. As a result some totals will not equal the sum of their components. Cells with 0 values have not been affected by confidentialisation. Refer to the footnotes for the tables where confidentialisation has been applied.

Where figures have been rounded, discrepancies may occur between totals and sums of the component items.

ABS published outputs are available free of charge from the ABS website. Click on 'Statistics' to gain access to the full range of ABS statistical and reference information. For details on products scheduled for release in the coming week, click on the Future Releases link on the ABS homepage.

Customised tables based on the data available in this publication is available through a paid data consultancy. Provide details through a Consultancy Request Form to find out more information. 

A range of socio-demographic data is available from the ABS Causes of Death collection including age, sex, and Aboriginal and Torres Strait Islander origin. This data has been coded and presented on standard classifications developed by the ABS. Where these are not released in the Causes of Death published outputs, they can be sourced on request from the ABS. 

Sex and gender

The 'sex' variable has traditionally been interpreted as reflecting the sex of the deceased, as reported at birth. In recent years, some states and territories have amended their jurisdictional-based Births, Deaths and Marriages legislation to allow for gender identity to be reported or updated on birth and death registrations. For a death registration, the change in legislation means that a person’s gender identity may be recorded. The terms 'sex' and 'gender' are interrelated and often used interchangeably, however they are two distinct concepts, and a person's sex may differ to their gender identity. Data for 'sex' in this publication may refer to:

• the person's sex reported at birth. This is currently how the vast majority of deaths are captured.
• the person's gender identity.

Data for sex is output in tables as ‘males’ and ‘females’ only. Sex not stated may be included in totals for perinatal deaths.

With the legislative changes, there are now instances in the data where a person has died from a cause of death that is not traditionally considered to be consistent with their reported sex. For example, prostate cancer may be recorded for a female, or ovarian cancer may be recorded for a male. While the number of such deaths is very small, they are expected to increase over time.

Aboriginal and Torres Strait Islander origin

The Aboriginal and Torres Strait Islander origin is captured through the death registration process and coded and presented in this publication based on the ABS Indigenous Status classification, see Indigenous Status Standard, 2014. For details of how the Aboriginal and Torres Strait Islander origin is derived for each state and territory and changes to this derivation over time, refer to the Deaths of Aboriginal and Torres Strait Islander people section.

Statistical geographic areas

Since the publication of Causes of Death, Australia, 2011, the ABS has released data based on the Australian Statistical Geography Standard (ASGS). The ASGS is a hierarchical classification system that defines more stable, consistent and meaningful areas than those of the Australian Standard Geographical Classification (ASGC), which was used to define geographical areas for output prior to the release of 2011 reference year data. Under the ASGS, the usual residence of the deceased is coded to the meshblock level. For further information, refer to the Australian Statistical Geography Standard (ASGS) Edition 3, July 2021 - June 2026. 

Causes of death statistics are presented at the national, state/territory and greater capital city/rest of state levels in this publication. These statistics have been compiled based on the state or territory of usual residence of the deceased, regardless of where in Australia the death occurred and was registered. Deaths of persons usually resident overseas which occur in Australia are included in the state/territory in which their death was registered. Usual residence data at the sub-state level reflects the 2021 version of the ASGS. 

Socio-Economic Indexes for Areas

Socio-Economic Indexes for Areas (SEIFA) is an ABS product that ranks areas in Australia according to relative socio-economic advantage and disadvantage. The indexes are based on information from the five-yearly Census of Population and Housing. 

SEIFA quintiles used in this publication are based on the Index of Relative Socio-economic Disadvantage (IRSD). This index is a general socio-economic index that summarises a range of information about the economic and social conditions of people and households within an area.

A low score indicates relatively greater disadvantage. For example, many households with low income, or many people without qualifications, and many people in low skilled occupations.

A high score indicates a relative lack of disadvantage. For example, few households with low incomes, few people without qualifications, and few people in low skilled occupations. A high score is not an indicator of advantage; rather it is an indicator of the absence of disadvantage. 

SEIFA quintiles represent approximately 20% of the national population, but do not necessarily represent 20% of the population in each state and territory. Disaggregation by SEIFA is based on a person’s usual residence aligned to geography based on 2021 ASGS Remoteness Area structure. Correspondence files are sourced from the ASGS: Main Structure and Greater Capital City Statistical Areas. Data presented by SEIFA reflects the 2021 version of the ASGS.

Country of birth

The country of birth of the deceased is coded and presented based on the Standard Australian Classification of Countries (SACC). Deaths coded according to the SACC reflect the country of birth of the deceased, as opposed to ancestry. This classification groups neighbouring countries into progressively broader geographic areas on the basis of their similarity in terms of social, cultural, economic and political characteristics. For further information, refer to the Standard Australian Classification of Countries (SACC).

The International Classification of Diseases (ICD) is the international standard classification for epidemiological purposes and is designed to promote international comparability in the collection, processing, classification, and presentation of causes of death statistics. The classification is used to classify diseases and causes of disease or injury as recorded on many types of medical records as well as death records. The ICD has been revised periodically to incorporate changes in the medical field. Currently the ICD 10th revision is used for Australian causes of death statistics.

The ICD-10 is a variable-axis classification meaning that the classification does not group diseases only based on anatomical sites, but also on the type of disease. Epidemiological data and statistical data is grouped according to:

• epidemic diseases
• constitutional or general diseases
• local diseases arranged by site
• developmental diseases
• injuries.

For example, a systemic disease such as sepsis is grouped with infectious diseases; a disease primarily affecting one body system, such as a myocardial infarction, is grouped with circulatory diseases; and a congenital condition, such as spina bifida, is grouped with congenital conditions.

For further information and access to versions of the ICD refer to WHO International Classification of Diseases (ICD).

Updates to the ICD

The Classification and Statistics Advisory Committee (CSAC), a WHO advisory group on updates to the ICD, maintains the cumulative and annual lists of approved updates to the classification. The updates to the ICD are of numerous types including the addition and deletion of codes, changes to coding instructions and modification and clarification of terms.

From the 2013 reference year, the ABS implemented a new automated coding system called Iris. The 2013-2023 data coded in the Iris system applied updated versions of the ICD-10 when coding multiple causes of death, and when selecting the underlying cause of death. The 2023 causes of death data presented in this publication was coded using version 5.8.0 of Iris software which applied the WHO ICD-10 updates (2020 version). For coding of 2021 data, the dictionary was updated to reflect new codes added including for vaccine deaths and long COVID-19. More information on Iris and ICD-10 versioning can be found in the table below. For details of further impacts of this change from 2013 data onwards, see the technical notes ABS Implementation of the Iris Software: Understanding Coding and Process Improvements  in the Causes of Death, Australia, 2013 publication and Updates to Iris coding software: Implementing WHO updates and improvements in coding processes in the Causes of Death, Australia, 2018 publication.

Coding of COVID-19

In response to the COVID-19 pandemic, the World Health Organization (WHO) issued the ICD emergency codes U07.1 COVID-19, virus identified and U07.2 COVID-19, virus not identified. A death directly due to COVID-19 is defined by the WHO as a death resulting from a clinically compatible illness, in a probable or confirmed COVID-19 case, unless there is a clear alternative cause of death that cannot be related to COVID disease (e.g. trauma). There should be no period of complete recovery from COVID-19 between illness and death. 

In 2021, COVID-19 vaccinations were introduced globally. The World Health Organization subsequently issued the ICD-10 emergency code U12.9 (COVID-19 vaccines causing adverse effects in therapeutic use, unspecified) to capture adverse effects of COVID-19 vaccines in therapeutic use. This code allows COVID-19 vaccine-related deaths to be identified separately from deaths involving adverse reactions to other vaccines and biological substances. 

In summary, the following new emergency codes have been issued by WHO since 2020 in response to the emergence of COVID-19 to be used when coding causes of death for statistical purposes: 

• U07.1 COVID-19 virus identified - This code is used when COVID-19 is confirmed by laboratory testing.
• U07.2 COVID-19 virus not identified - This code is used for suspected or clinical diagnoses of COVID-19 where testing is not completed or inconclusive.
• U08 Personal history of COVID-19 - This code is used when a person has recovered from COVID-19 and no long-term effects have been certified as contributing to an individual’s death and/or COVID-19 is listed on the death certificate but it did not contribute to the death. These deaths are not included in COVID-19 mortality tabulations.
• U09 Post COVID-19 condition - This code is used to link long-term conditions including chronic lung conditions that are the result of the virus. These deaths are included in COVID-19 mortality tabulations as associated causes of death. 
• U10 Multisystem inflammatory syndrome associated with COVID-19 - This code is used to identify people who have died from COVID-19 where the virus has led to a multi-inflammatory response syndrome. 
• U11 Need for immunization against COVID-19 - This code has been assigned to deaths where an incidental mention of a COVID-19 vaccine has been listed on the death certificate. An incidental mention is where the doctor has stated that a person recently received a vaccine but it did not have any contribution to death. 
• U12 COVID-19 vaccines causing adverse effects in therapeutic use - This code allows COVID-19 vaccine-related deaths to be identified separately from deaths involving adverse reactions to other vaccines and biological substances.

A further code ‘Z03.8 Examination for observation and other specified reasons’ can be used to record a negative test result in order to capture this information on the death certificate. These deaths are not tabulated as being due to COVID-19. 

Other significant historical updates

With the introduction of 2019 ICD-10 updates there was a change to the code for deaths due to poisoning by, and exposure to, carbon monoxide and other gases and vapours. This change was applied to poisoning across multiple intents including accident (X47), intentional (X67), assault (X88) and undetermined intent (Y17). There are now multiple four-digit options for X47, X67, X88 and Y17. Previously, when a death occurred as a result of poisoning by, and exposure to, carbon monoxide and other gases and vapours, there was no option to further identify carbon monoxide from other gases and vapours as well as to specify the source of the carbon monoxide. ABS mortality coders are now required to choose from multiple four-digit options to further specify the death:

• X47.0/X67.0/X88.0/Y17.0 carbon monoxide from combustion engine exhaust 
• X47.1/X67.1/X88.1/Y17.2 carbon monoxide from utility gas
• X47.2/X67.2/X88.2/Y17.2 carbon monoxide from other domestic fuels
• X47.3/X67.3/X88.3/Y17.3 carbon monoxide from other sources
• X47.4/X67.4/X88.4/Y17.3 carbon monoxide from unspecified sources 
• X47.8/X67.8/X88.8/Y17.8 other specified gases and vapours 
• X47.9/X67.9/X88.9/Y17.9 unspecified gases and vapours 

Prior to the 2013 reference year, the 2006 version of the ICD-10 was the most recent version used for coding deaths, with the exception of two updates that were applied after the 2006 reference year. The first update was implemented in 2007 and related to the use of mental and behavioural disorders due to psychoactive substance use, acute intoxication (F10.0, F11.0...F19.0) as an underlying cause of death. If the acute intoxication initiated the train of morbid events it is now assigned an external accidental poisoning code (X40-X49) corresponding to the type of drug used. For example, if the death had been due to alcohol intoxication, the underlying cause before the update was F10.0, and after the update the underlying cause is X45, with poisoning code T51.9. The second update implemented from the 2009 reference year was the addition of Influenza due to certain identified virus (J09) to the Influenza and Pneumonia block. This addition was implemented to capture deaths due to Swine flu and Avian flu, which were reaching health epidemic status worldwide.

The cumulative List of Official ICD-10 Updates can be found online.

Conditions on the medical certificate of cause of death are coded to the International Classification of Diseases, 10th revision (see Classifications section for more information). All causes of death can be grouped to describe the type of death, whether it be from a disease or condition, or from an injury, or whether the cause is unknown. These are generally described as:

• Natural Causes - deaths due to diseases (for example diabetes, cancer, heart disease etc.) (A00-Q99, R00-R98)
• External Causes - deaths due to causes external to the body (for example intentional self-harm, transport accidents, falls, poisoning etc.) (V01-Y98)
• Unknown Causes - deaths where it is unable to be determined whether the cause was natural or external (R99).

Where an accidental or violent death occurs, the underlying cause is classified according to the circumstances of the fatal injury, rather than the nature of the injury, which is coded separately. For example, a motorcyclist may crash into a tree (V27.4) and sustain multiple fractures to the skull and facial bones (S02.7), which leads to death. The underlying cause of death is the crash itself (V27.4), as it is the circumstance which led to the injuries that ultimately caused the death.

From the 2013 reference year, the ABS implemented a new automated coding system called Iris. The 2013-2023 data coded in the Iris system applied updated versions of the ICD-10 when coding multiple causes of death, and when selecting the underlying cause of death. The 2023 reference year causes of death data presented in this publication was coded using version 5.8.0 of Iris software which applied the WHO ICD-10 updates (2020 version). For coding of 2021 data, the dictionary was updated to reflect new codes added to the ICD, including for COVID-19 vaccine-related deaths and long COVID-19. More information on Iris and ICD-10 versioning can be found in the table below. For details of further impacts of this change from 2013 data onwards, see the technical notes ABS Implementation of the Iris Software: Understanding Coding and Process Improvements in the Causes of Death, Australia, 2013 publication and Updates to Iris coding software: Implementing WHO updates and improvements in coding processes in the Causes of Death, Australia, 2018 publication.

The quality of causes of death coding can be affected by changes in the way information is reported by certifiers, by lags in completion of coroner cases and the processing of the findings. While changes in reporting and lags in coronial processes can affect coding of all causes of death, those coded to Chapter XVIII: Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified and Chapter XX: External causes of morbidity and mortality are more likely to be affected because the code assigned within the chapter may vary depending on the coroner's findings (in accordance with ICD-10 coding rules).

Where a case remains open on the NCIS at the time the ABS ceases processing, and insufficient information is available to code a cause of death (e.g. a coroner certified death was yet to be finalised by the coroner), less specific ICD codes are assigned, as required by the ICD coding rules.

The specificity with which open cases are able to be coded is influenced by the amount and type of information available on the NCIS. The amount of information available for open cases varies considerably from no information to detailed police, autopsy and toxicology reports.

The manner or intent of an injury which leads to death, is determined by whether the injury was inflicted purposefully or not. When an injury was inflicted purposefully (intentional), a determination should be made as to whether the injury was self-inflicted (suicide) or inflicted by another person (assault). However, intent cannot be determined in all cases.

See Data Quality – Coroner certified deaths data for further information about quality considerations for coroner certified data.

ICD-10 codes are assigned to all conditions on a medical certificate of cause of death and rules applied to select an underlying cause of death. The WHO defines the underlying cause of death as the disease or injury that initiated the train of morbid events leading directly to death. Accidental and violent deaths are classified according to the external cause, that is, to the circumstances of the accident or violence which produced the fatal injury rather than to the nature of the injury. Diseases and injuries which are listed on the death certificate and not selected as the underlying cause are referred to as associated causes of death. The majority of data presented in the data cubes in this publication is tabulated according to the underlying cause of death. 

Multiple causes of death include all causes and conditions reported on the death certificate (i.e. both underlying and associated causes; see the Glossary for further details). As all entries on the death certificate are taken into account, multiple causes of death statistics are valuable in recognising the impact of conditions and diseases which are less likely to be an underlying cause, highlighting relationships between concurrent disease processes, and giving an indication of injuries which occur as a result of specific external events. These features of multiple causes of death data provide a more in depth picture of mortality in Australia.

When analysing data on multiple causes of death, data can be presented in two ways: by counts of deaths or by counts of mentions. When analysis is conducted by counts of death, the figures are describing the number of people who have died with a particular disease or disorder. Multiple Causes of Death data derived from counts of mentions is the total number of incidences of a particular disease or disorder on the death certificate. For example, an individual may have had Breast cancer (C50) and then developed Secondary lung cancer (C78.0). This individual would be counted once if counts were by the number of deaths from cancer, but twice if the counts were by the number of mentions of cancer. Care should be taken to differentiate between counts and mentions when analysing multiple causes of death data.

Changes in patterns of mortality are studied by policy makers and researchers to improve health outcomes for all Australians. However, changes in patterns of mortality can occur for many reasons. Changes can reflect a real increase or decrease in the prevalence of a disease or disorder, or a change in medical treatment. With an ageing population, people are more likely to die with multiple co-morbid conditions, many of which may be listed on the death certificate. The multiple cause of death data can provide more meaningful insights into relationships between diseases and how these may contribute to mortality. This information cannot be obtained from focussing on the underlying cause of death data alone.

Mortality data changes can also be a result of administrative processes which can potentially impact on the data, for example, International Classification of Disease (ICD) coding classification changes and updates, and differences in how deaths are certified. Analysis of the multiple causes of death data can give a deeper understanding of how the complete dataset may be affected by both real and administrative changes.

The table below provides selected examples of causes of death and their propensity to be reported as an underlying cause of death, compared to an associated cause of death. Numbers presented in the table are based on 2023 data.

When making comparisons between road deaths from the ABS Causes of Death collection and road deaths from other sources, the scope and coverage rules applying to each collection should be considered. It should be noted that the number of road-traffic-related deaths attributed to transport accidents for 2023 is expected to change as data is subject to the revisions process. See Data Quality - Revisions process for more information about the ABS revisions process.

The number of deaths recorded as Assault (X85-Y09, Y87.1) i.e. murder, manslaughter and their sequelae, published in the ABS Causes of Death publication, differ from those published by the ABS in Recorded Crime - Victims, Australia. Reasons for the different counts include differences in scope and coverage between the two collections, as well as legal proceedings that are pending finalisation. It is important to note that the number of deaths attributed to assault for 2023 is expected to change as data is subject to the revisions process. See Data Quality - Revisions process for more information about the ABS revisions process.

The ICD-10 code Y07 Perpetrator of assault, maltreatment and neglect is used to capture information about the perpetrator of deaths that have occurred as a result of an assault, maltreatment or neglect. The ABS has reviewed use of this code to ensure it has been used consistently and can be used to identify if the victim was assaulted by a family member. 

The Y07 code is being applied as follows:

The source of all cause of death data for the ABS is collected through the civil registration system either by the Medical Certificate of Cause of Death (MCCD) for doctor certified deaths or the pathology report or coronial findings for coroner referred deaths (accessed via the National Coronial Information System). This enables identification of the underlying cause of death and other associated causes and risk factors. Civil-registration-based data is not directly comparable with that released from disease surveillance systems which are designed to release information rapidly on both infections and mortality. Information about mortality sourced from the registration-based system takes longer to receive than information reported through the surveillance system, but it is more comprehensive and can provide important additional insights into deaths from COVID-19. 

COVID-19 vaccine-related deaths

The civil registration system also captures deaths which may be caused by COVID-19 vaccines. The World Health Organization issued the ICD-10 emergency code U12.9 (COVID-19 vaccines causing adverse effects in therapeutic use). This code allows COVID-19 vaccine-related deaths to be identified separately from deaths involving adverse reactions to other vaccines and biological substances.

Independent analysis and interpretation of deaths data by authorities such as the Therapeutic Goods Administration (TGA) is not conveyed to the ABS or reflected in coding outputs. Due to the scope of the ABS deaths collection, data received and published by the ABS may differ from data collected through the TGA's independent investigations into COVID-19 vaccine-related deaths. The ABS and the TGA have communicated and understand that there are differences in how a death may be categorised as being related to a COVID-19 vaccine. These differences may include scope (as described) and the timing of coding and investigations (the TGA regularly updates data in relation to vaccines, whereas the ABS is reporting on coded data at a point in time). The ABS and the TGA will continue to work together to ensure that datasets remain consistent as possible whilst taking into account the known differences in each agency’s reporting scopes.

• There have been 16 deaths in Australia for which the information provided to the ABS indicated that COVID-19 vaccination was the underlying cause of death, 15 of which were registered in 2021.
• Of these, 14 were certified by a coroner and 2 were certified by a doctor.
• Around one-third of deaths (35.7%) assigned as being due to the COVID-19 vaccine have open coronial cases meaning they are in scope of the ABS revisions process. Additional information will be reviewed by the ABS in relation to these deaths as it is received.
• There were 9 deaths where the vaccine caused a complication which exacerbated an existing condition but did not in itself cause death. 
• The TGA has identified 14 reports where the cause of death was linked to vaccination. Refer to the TGA COVID-19 vaccine safety reports for further details on the TGA’s vaccine safety monitoring process. 

Ranking causes of death is a useful method of describing patterns of mortality in a population and allows comparison over time and between populations. However, different methods of grouping causes of death can result in a vastly different list of leading causes for any given population. A ranking of leading causes of death based on broad cause groupings such as 'cancers' or 'heart disease' does not identify the leading causes within these groups, which is needed to inform policy on interventions and health advocacy. Similarly, a ranking based on very narrow cause groupings or including diseases that have a low frequency, can be meaningless in informing policy.

Tabulations of leading causes presented in this publication are based on research presented in the Bulletin of the World Health Organization, Volume 84, Number 4, April 2006, 297-304. The determination of groupings in this list is primarily driven by data from individual countries representing different regions of the world. Other groupings are based on prevention strategies, or to maintain homogeneity within the groups of cause categories. Since the aforementioned bulletin was published, a decision was made by WHO to include deaths associated with the H1N1 influenza strain (commonly known as swine flu) in the ICD-10 classification as Influenza due to certain identified influenza virus (J09). This code has been included with the Influenza and Pneumonia leading cause grouping in the Causes of Death publication since the 2009 reference year.

Since 2015, the ABS includes C26.0 (malignant neoplasm of the intestinal tract, part unspecified) in the WHO leading cause grouping for Malignant neoplasm of colon, sigmoid, rectum and anus (now C18-C21, C26.0). For further details on the reasoning behind the inclusion of C26.0 in this leading cause grouping, see Complexities in the measurement of bowel cancer in Australia, in Causes of Death, Australia, 2015. This change has been applied in this publication to data for all reference years that appear in tables involving leading cause tabulations. This differs to publications prior to 2015, for which C26.0 was not included in this leading cause grouping, and also differs to the suggested WHO tabulation of leading causes for these cancers. Comparisons with data for this leading cause, and associated leading cause rankings, as they appear in previous publications should therefore be made with caution.

Since 2017, the ABS includes Y87.0 (Sequelae of intentional self-harm), Y87.1 (Sequelae of assault) and Y85 (Sequelae transport accidents) in the WHO leading cause grouping for Intentional self-harm (now X60-X84, Y87.0), Assault (now X85-Y09, Y87.1) and Land transport Accidents (V01-V89, Y85). This change has been applied to harmonise data between the WHO leading cause grouping and subject-specific data cubes for intentional self-harm, assault and transport accidents which is published as part of the ABS Causes of Death collection. This change applies to publication data for all reference years that appear in tables involving leading cause tabulations. This differs to previous publications, where Y87.0, Y87.1 and Y85 were not included in these leading cause groupings, and also differs to the suggested WHO tabulation of leading causes. Comparisons with data for these leading causes, and associated leading cause rankings, as they appear in previous publications should therefore be made with caution.

Since 2020, the ABS includes COVID-19 deaths as a WHO leading cause group. COVID-19 deaths include ICD-10 codes U07.1 COVID-19 virus identified, U07.2 COVID-19 virus not identified, and U10.9 Multisystem inflammatory syndrome associated with COVID-19, unspecified.

Deaths coded to Chapter XVIII: Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R99) are not included in tabulations of leading causes due to the unspecified nature of these causes. Many deaths coded to this chapter are likely to be affected by revisions, and hence recoded to more specific causes of death as they progress through the revisions process. An exception to this is Ill-defined and unknown causes of mortality (R95-R99), which is included in the analysis for deaths of those under the age of one year, as Sudden Infant Death Syndrome (R95) and Sudden Unexpected Death in Infancy (R99) is included in this cause grouping. Up until the 2022 issue of this publication, the Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R99) grouping was included when making comparisons between the Aboriginal and Torres Strait Islander and non-Indigenous populations. This aligned with the WHO recommendation to include this grouping when comparing smaller populations that may have higher numbers of deaths due to this cause grouping. However, further analysis has shown that once data is final, this grouping no longer appears in the top 10 leading causes for Aboriginal and Torres Strait Islander deaths. Therefore this grouping will no longer be included in outputs showing leading causes by Indigenous status.  

Data by leading causes is presented in the Underlying causes of death data cubes (1-9) and the '15. Deaths of Aboriginal and Torres Strait Islander Australians' data cube in this publication.

Death rates enable more meaningful comparisons between population groups of different sizes by presenting the number of deaths against population estimates. Rates throughout this publication are calculated as the number of deaths per 100,000 people (with the exception of perinatal and infant death rates discussed below). This differs from the presentation of rates in Deaths, Australia which presents rates per 1,000 people.

From the 2022 issue of this publication, numbers have been presented by registration year rather than reference year. Death rates in 2023 are based on registration year for the numerator and reference-year-based population estimates for the denominator.

Crude and age-specific death rates

The crude death rate (CDR) is the number of deaths registered during the year per 100,000 estimated resident population at 30 June of the same year.

Age-specific death rates (ASDRs) are the number of deaths registered during the year at a specified age per 100,000 of the estimated resident population of the same age at the mid-point of the same year (30 June).

Infant mortality rates (IMRs) (those under 1 year of age) are calculated per 1,000 live births for that year.

Perinatal death rates

Perinatal death rates are the number of perinatal deaths in a registration year (i.e. stillbirths and neonatal deaths) per 1,000 ‘all births’ in the same reference year. All births comprises all live births plus all stillbirths (ie. gestation at least 20 weeks or birth weight at least 400 grams) for a specific year.

Fetal death rates are the number of stillbirths in a registration year per 1,000 'all births' in the same year.

Neonatal death rates are the number of deaths within 28 completed days of live born babies in a registration year per 1,000 live births in the same reference year.

Age-standardised death rates (SDRs)

Age-standardised death rates enable the comparison of death rates over time and between populations of different age structures. Along with adult, infant and child mortality rates, they are used to determine whether the mortality rate of the Aboriginal and Torres Strait Islander population is declining over time, and whether the gap between Aboriginal and Torres Strait Islander and non-Indigenous populations is narrowing. The ABS uses the direct method of age-standardisation as it allows for valid comparisons of mortality rates between different study populations and across time. This method was agreed to by the ABS, Australian Institute of Health and Welfare (AIHW) and other stakeholders. For further information see: AIHW (2011) Principles on the use of direct age-standardisation in administrative data collections: for measuring the gap between Indigenous and non-Indigenous Australians. Cat. no. CSI 12. Canberra: AIHW.

The direct method has been used throughout the publication and data cubes for age-standardised death rates. Age-standardised death rates for specific causes of death with fewer than 20 deaths have not been published due to issues of robustness.

For further information, see Appendix: Principles on the use of direct age-standardisation, from Deaths, Australia, 2010.

In this publication, mortality rates for 2014-2023 for the total population and Aboriginal and Torres Strait Islander people have been calculated using population estimates and projections for the relevant year based on the 2021 Census. Non-Indigenous estimates for the relevant years have been derived by subtracting Aboriginal and Torres Strait Islander population estimates from the total Australian estimated resident population (ERP). In previous publications, rates for Aboriginal and Torres Strait Islander people have been based on the 2016 Census and the 2021 Census for other populations. Rates are not comparable with those presented in previous publications. See Estimates and Projections, Aboriginal and Torres Strait Islander Australians for more information.

For more details on data used in calculating death rates, refer to the Appendix - data used in calculating death rates.

The ABS accesses the National Coronial Information System (NCIS) to obtain causes of death information for coroner referred deaths including suicides. Information regarding the causes of death and associated factors is obtained from various reports including police, toxicology, autopsy and coronial findings.

A death may be coded as due to suicide when:

• A coroner makes a formal finding stating the death was due to suicide.
• If a formal finding is not made (i.e. the coroner does not state the intent), an investigation of information on the NCIS may indicate a death was due to suicide. Information that would be used by a mortality coder to record a death as being due to suicide includes indications by the person that they intended to take their own life, the presence of a suicide note, or knowledge of previous suicide attempts.  
• For an open coronial investigation, the police may record the death as being a suspected suicide. Open cases are reviewed by the ABS when closed as part of the annual revisions process.

These coding guidelines have been applied since 1 January 2007. Previously, coding rules required a coroner to determine a death as intentional self-harm for it to be coded to suicide.

The two flow charts below highlight the guidelines used by the ABS when coding a death to intentional self-harm for open and closed coroner cases, where the intent status at the time of coding is neither intentional self-harm nor assault. In these cases, the ABS considers additional information available on NCIS, such as the mechanism and other available data (e.g. the presence of a suicide note or previous suicide attempts) when determining the intent of such deaths for coding purposes.

From 2006 onwards, the ABS implemented a revisions process for coroner certified deaths where deaths with an open coronial investigation at the time of initial coding by the ABS have since been finalised.  The revisions process has enabled additional deaths due to suicide to be identified beyond initial processing. It is recognised that in the four years prior to the implementation of the revisions process (2001-2005), suicide deaths may have been understated as the ABS began using the National Coronial Information System as the sole source for coding coroner referred deaths.

The 2023 published outputs include 2023 preliminary data, 2022 preliminary revised data and 2021 revised data. Data for reference years up to and including 2020 are considered final and no longer subject to the revisions process. The number of deaths attributed to intentional self-harm for 2021, 2022 and 2023 is expected to increase as data is reviewed as part of the revisions process. For more details on the impact of revisions on numbers of suicide deaths, refer to the Technical Note: Updates to 2020, 2021 and 2022 suicide data in Causes of Death, Australia methodology, 2022.

Deaths that are referred to the coroner are more likely to take longer to be registered, especially those which are due to external causes, including suicide, homicide and drug-related deaths. These delayed registrations can sometimes create large yearly variation in some causes of deaths and for some populations, for example deaths of Aboriginal and Torres Strait Islander people.

Over recent years, for some jurisdictions, there has been an increasing delay in information flowing between the coroner court and the National Coronial Information Service (NCIS), including uploading autopsy reports, toxicology reports and coronial findings, and updating the closure status. Some jurisdictions are more affected than others. This may mean the number of deaths coded to suicide will continue to change as further information is received and data is revised. For statistics on case closure and document attachment for each jurisdiction, refer to the Operational Statistics published on the NCIS website.

More broadly, various factors including administrative and system changes, certification practices, the timeliness of information flows, classification updates or coding rule changes can impact on the mortality dataset. The sections below highlight state-specific administrative factors that have had an impact on the number of suicide deaths over time. Data users should be cautious when making comparisons between reference periods.

As a result of two reconciliation exercises conducted jointly between the ABS and the Victorian Registry of Births Deaths and Marriages (Victorian RBDM), additional historical registrations of suicide were identified that had not been previously provided to the ABS.

• The first exercise (conducted in the first quarter of 2020) resulted in the identification of an additional 180 suicides that were registered in Victoria in 2017 (88 suicides) and 2018 (92 suicides) but not previously supplied to the ABS. 
• The second exercise (conducted in the first quarter of 2022) resulted in the identification of an additional 72 suicides that were registered in Victoria in 2013 (20 suicides), 2014 (14 suicides), 2015 (8 suicides) and 2016 (30 suicides) that were not previously supplied to the ABS.  

From the 2022 issue of the publication, data is presented by year of registration including the additional Victorian registrations obtained during both reconciliation exercises. This means the number of deaths for a particular year is more representative of the deaths that were registered in that year. For more information on these deaths and how they were presented in previous publications, refer to Technical note: Victorian additional registrations and time series adjustment in Causes of Death, Australia, 2019 and Technical note: Victorian additional registrations (2013-2016) in Causes of Death, Australia, 2021.

Additionally, as part of the implementation of the new registration system in Victoria in February 2019, there was a change in the way coroner referred deaths are reported to the ABS. Previously, only cases where the coronial case had closed were reported to the ABS, often leading to significant delays in reporting. From 2019, interim registrations (open cases) have been submitted to the ABS resulting in more timely delivery of death registration information to the ABS and an improvement in the quality of preliminary coding in relation to deaths due to suicide.

The Aboriginal and Torres Strait Islander origin of a deceased person is captured through the death registration process. It is noted on the Death Registration Form (DRF) and the Medical Certificate of Cause of Death (MCCD). However it is recognised that not all such deaths are captured through these processes, which may lead to under-identification. While data is provided to the ABS for the Aboriginal and Torres Strait Islander origin of the deceased for more than 99% of all deaths, there are sometimes concerns regarding the accuracy of the data.

The ABS Deaths and Causes of Death reports identify a death as being of an Aboriginal and Torres Strait Islander person where the deceased is recorded as Aboriginal, Torres Strait Islander, or both on the DRF. The Aboriginal and Torres Strait Islander origin is also derived from the MCCD. If the Aboriginal and Torres Strait Islander origin reported in the DRF does not align with the MCCD, an identification from either source that the deceased was an Aboriginal and/or Torres Strait Islander person is generally given preference over non-Indigenous or an unknown status, although there are some rare exceptions to this.

The use of this information from the MCCD has been introduced at different times across jurisdictions depending on when systems and processes have allowed for the ABS to use as follows:  

• From 2007 for South Australia, Western Australia, Tasmania, the Northern Territory and the Australian Capital Territory.
• From 2015 for Queensland. This resulted in a noticeable decrease in the number of deaths for which the Indigenous status was ‘not stated’ and an increase in the number of deaths identified as Aboriginal and Torres Strait Islander people in Queensland in comparison to previous years. This impact is discussed in Life Tables for Aboriginal and Torres Strait Islander Australians (see Data linkage to derive Aboriginal and Torres Strait Islander deaths identification rates).
• From 2022 for New South Wales. This resulted in a marked increase in the number of deaths identified as Aboriginal and/or Torres Strait Islander and a corresponding reduction in the number of deaths for which Indigenous status was not stated. For more information on this change and the impacts refer to Technical Note: The impact of using two sources for deriving the Indigenous status of deaths in NSW in 2022.
• From 2023 for Victoria, information from the MCCD has been used for the first time. For more information on this change and the impacts refer to Technical Note: The impact of using multiple sources for deriving the Indigenous status of deaths in 2023 – changes for Victoria and coroner referred deaths.

From 2023, the ABS has used information captured on the National Coronial Information System (NCIS) during the coronial investigation process in the derivation of Indigenous status. If the Aboriginal and Torres Strait Islander origin reported in the DRF or MCCD does not align with that on the NCIS, an identification from any source that the deceased was an Aboriginal and/or Torres Strait Islander person is given preference over non-Indigenous or an unknown status. This change in process affects coroner deaths in all jurisdictions for the first time in 2023, with the exception of New South Wales for which a similar enhancement was introduced in 2022. For more information on this change and the impacts refer to Technical Note: The impact of using multiple sources for deriving the Indigenous status of deaths in 2023 – changes for Victoria and coroner referred deaths.

There are several data collection forms on which people are asked to state whether they are of Aboriginal and Torres Strait Islander origin. Due to a number of factors, the results are not always consistent. The likelihood that a person will identify, or be identified, as an Aboriginal and Torres Strait Islander person on a specific form is known as their propensity to identify.

Propensity to identify as an Aboriginal and Torres Strait Islander person is determined by a range of factors, including:

• how the information is collected (e.g. census, survey, or administrative data)
• who provides the information (e.g. the person in question, a relative, a health professional, or an official)
• the perception of why the information is required, and how it will be used
• educational programs about identifying as an Aboriginal and Torres Strait Islander person
• cultural aspects and feelings associated with identifying as Aboriginal and Torres Strait Islander Australian.

Additionally, a number of deaths occur each year for which the Aboriginal and Torres Strait Islander origin is not stated on any of the sources used to derive the Indigenous status of the deceased. In 2023, there were 336 deaths registered in Australia for whom the Aboriginal and Torres Strait Islander origin was not stated, representing approximately 0.2% of all deaths registered, a decrease compared with 2022 (0.5%). This difference was largely driven by fewer deaths of not stated Aboriginal and Torres Strait Islander origin with a state of usual residence in Victoria (from 558 in 2022 to 48 in 2023). 

Caution should be exercised when interpreting data for Aboriginal and Torres Strait Islander Australians presented in this publication, especially with regard to year to year changes. Data presented may underestimate the number of deaths of Aboriginal and Torres Strait Islander people due to factors relating to form completion and propensity for an informant to identify the deceased as being of Aboriginal and Torres Strait Islander origin. Additionally, a higher proportion of deaths of Aboriginal and Torres Strait Islander people are referred to a coroner. Coroner referred deaths can take longer to register which may cause some disparities in annual registration data.

Information on causes of death relating to Aboriginal and Torres Strait Islander people is included in articles and data cubes in this publication. Limited data is presented for all states and territories, with more detailed data reported by jurisdiction of usual residence for New South Wales, Queensland, South Australia, Western Australia and the Northern Territory only. These jurisdictions have been found to have a higher quality of identification of Aboriginal and Torres Strait Islander origin allowing more robust analysis of data. For 2023, due to improvements in the quality of Indigenous status data for deaths in Victoria, data for this jurisdiction is also included in statistics on suicide deaths in relevant articles and data cubes in this publication. Individual state/territory disaggregations of deaths of Aboriginal and Torres Strait Islander Australians by WHO Leading Causes are presented for New South Wales, Victoria, Queensland, South Australia, Western Australia and the Northern Territory. Data for those with a usual residence in Tasmania and the Australian Capital Territory remain excluded from the more detailed analysis in line with usual national reporting guidelines. 

Rates revised using 2021 Census based population estimates

In this publication, mortality rates for 2014-2023 for the total population and Aboriginal and Torres Strait Islander people have been calculated using population estimates and projections for the relevant year based on the 2021 Census. Non-Indigenous estimates for the relevant years have been derived by subtracting Aboriginal and Torres Strait Islander population estimates from the total Australian estimated resident population (ERP). In previous publications, rates for Aboriginal and Torres Strait Islander people have been based on the 2016 Census and the 2021 Census for other populations. Rates are not comparable with those presented in previous publications. See Estimates and Projections, Aboriginal and Torres Strait Islander Australians and Guide to using historical estimates for comparative analysis and reporting for more information.

The ABS undertakes significant work aimed at improving Aboriginal and Torres Strait Islander identification. The ABS works closely with the state and territory RBDMs through the Civil Registration and Vital Statistics Australasia committee (CRVSA) to progress strategies aimed at improving Indigenous identification in a nationally consistent way.

The ABS produces estimates of life expectancy for Aboriginal and Torres Strait Islander people. For the latest estimates, refer to Aboriginal and Torres Strait Islander life expectancy. Estimates are presented for Australia, selected states and territories, remoteness areas and SEIFA (Index of Relative Socio-Economic Disadvantage). These estimates are produced using data from death records, the Census of Population and Housing and the Census Post Enumeration Survey (PES). In response to an independent review conducted in 2020, the ABS has made enhancements to the methods used to produce these estimates. For more information on these enhancements, refer to Updated method for 2020-2022 Aboriginal and Torres Strait Islander life expectancy estimates.  

The scope of the perinatal death statistics includes all registered stillbirths (at least 20 weeks' gestation or at least 400 grams' birth weight) and all registered neonatal deaths (all live born babies who die within 28 completed days of birth, regardless of gestation or birth weight). The ABS scope rules for stillbirths (also referred to as fetal deaths) are consistent with the legislated requirement for all jurisdictional Registries of Births, Deaths and Marriages to register all stillbirths which meet the above-mentioned gestation and birth weight criteria. Based on this legislative requirement, in the case of missing gestation and/or birth weight data, the fetal record is considered in scope and included in the dataset. A record is only considered out of scope if both gestation and birth weight data are present, and both fall outside the scope criteria (i.e. gestation of 19 weeks or fewer and birth weight of 399 grams or less). This scope was adopted for the 2007 Perinatal Deaths collection and applied to historical data for 1999-2006. For more information on the changes in scope rules see Perinatal Deaths, Australia, 2007 Explanatory Notes 18-20. These rules have been applied to all perinatal data presented in this publication.

The World Health Organization (WHO) definition of a perinatal death differs to that used by the ABS. The WHO definition includes all neonatal deaths, and those fetuses weighing at least 500 grams or having a gestational age of at least 22 weeks. A summary table based on the WHO definition of perinatal deaths is included in the Perinatal deaths data cube in this release (see Table 15.21).

The scope of the ABS Perinatal collection differs from other Australian data sources on perinatal deaths and therefore caution should be taken when using multiple sources for analysis. The ABS Perinatal collection is based on registered stillbirths and neonatal deaths sourced through jurisdictional Registries of Births, Deaths and Marriages and therefore may not include all perinatal deaths that have occurred in Australia. Neonatal death registrations are sourced through death registrations, while stillbirth registrations are sourced as follows:

• New South Wales, Victoria and Tasmania RBDMs provide the ABS with the birth registration. 
• Queensland, South Australia, the Northern Territory and the Australian Capital Territory RBDMs provide the ABS with the death registration. 
• Western Australia RBDM provides both the birth and death registrations. The ABS bases Western Australian data on the death registration. 

For Tasmania only, in addition to registered stillbirths, data includes stillbirths based on birth notifications that have not yet been registered. Prior to 2023, the ‘registration date’ for Tasmanian stillbirths was based on the date the stillbirth was first entered into the registry system (the insertion date), rather than the date on which the registration was finalised (the registration date). From 2023, where available, the registration date has been used, aligning reporting for all jurisdictions. For notifications of stillbirths that were not yet registered as at the time of finalising data for the reference period, the registration date is set to unknown. 

In ABS collections:

• Stillbirths are part of the Perinatal collection. They are not in scope of the Births, Deaths, or Causes of Death reports. 
• Neonatal deaths are in scope of the Deaths, Causes of Death and Perinatal reports.

Given the small number of perinatal deaths which occur in some states and territories, some data provided on a state/territory basis in this publication has been aggregated for South Australia, Western Australia, Tasmania, the Northern Territory, the Australian Capital Territory and Other Territories.

Perinatal death data reported by the ABS is not comparable with the National Perinatal Mortality Data Collection (NPMDC) coordinated by the AIHW. The ABS data is sourced from jurisdictional Registries of Births, Deaths and Marriages. This differs from the NPMDC whose data is sourced from health systems, including clinical records. The table below compares ABS and NPMDC numbers of stillbirths and neonatal deaths. It shows that the ABS perinatal dataset is affected by delayed registrations which results in an under count of perinatal deaths, especially those of stillbirths. Caution should be taken when interpreting this data. For more information on the AIHW collection, refer to Australia’s mothers and babies: Stillbirths and neonatal deaths.

For perinatal data in the Causes of Death, Australia, 2013 publication, the ABS began a review of coding of perinatal deaths, which resulted in an interim change to outputs. Neonatal deaths were no longer assigned an underlying cause of death when output in tables of all ages (refer to Changes to Perinatal Death Coding Technical Note in Causes of Death, Australia, 2013). Further review and consultation has resulted in a new method of coding. The new method creates a sequence of causes on a Medical Certificate of Cause of Perinatal Death which allows for an underlying cause of death to be assigned to a neonatal death. This aligns neonatal deaths to deaths of the general population which are certified using the Medical Certificate of Cause of Death. The change reinstates the condition arising in the mother being assigned as an underlying cause of death. This method has been applied from 2014, and has also been applied retrospectively to 2013 neonatal data. Please see the Changes to Perinatal Death Coding Technical Note in Causes of Death, Australia, 2014 for further details.

From 2013, changes have led to a reduction in the number of both stillbirths and neonatal deaths where a 'main condition in mother' was recorded. This has led to a reduction in deaths assigned within the code block P00-P04: Fetus and newborn affected by maternal factors and by complications of pregnancy, labour and delivery, as main condition in the mother. These changes affect data output in the Perinatal data cube only.

Doctor certified neonatal deaths with no causes of death information are coded to Conditions originating in the perinatal period, unspecified (P969). As these deaths have been certified by a doctor, the assumption is made that the neonate died of natural causes. Where a neonatal death is referred to a coroner, but no causes of death information is available, these deaths are coded to Other ill-defined and unspecified causes of mortality (R99). As a reportable death, it cannot be determined whether the neonate died of natural or external causes, in the absence of further information.

Live births and the number of stillbirths are used as the denominator in the calculation of mortality rates for perinatal deaths. See the 'Data Used in Calculating Death Rates' Appendix for details of the number of live births registered which have been used to calculate the stillbirth, neonatal and perinatal death rates shown in this publication. This Appendix also provides data on stillbirths used in the calculation of stillbirth and perinatal death rates. Also refer to ‘Live birth counts used in mortality rate denominators’ section of Data quality for information about the quality of live birth counts.

There are a very small number of stillbirth registrations provided to the ABS each year where the sex at birth has not been specified as male or female. This can be due to:

• administrative processes where the sex of the stillbirth has not been supplied to the ABS 
• a clinical determination of sex may not be able to be clearly determined. This may be due to a number of reasons including extreme prematurity or some congenital conditions.

Where the sex at birth has not been specified for a stillbirth, these deaths are included in total person counts only for tabulations by fetal deaths and all perinatal deaths (both fetal and neonatal deaths). There were 29 stillbirths registered in 2023 where the sex at birth was not specified.

Additional sources for identifying Indigenous status have improved reporting of 2023 Aboriginal and Torres Strait Islander deaths and intentional self-harm deaths in Victoria for 2018-2023. For more detail, refer to the Technical Note: The impact of using multiple sources for deriving the Indigenous status of deaths in 2023 – changes for Victoria and coroner referred deaths.