1 This publication contains statistics on causes of death for Australia, together with selected statistics on perinatal deaths.
2 Statistics on perinatal deaths for the 2007-2009 reference years were published separately in Perinatal Deaths, Australia, 2009 (cat. no. 3304.0).
3 In order 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 2018, 88.1% of deaths were certified by a doctor. The remaining 11.9% were certified by a coroner.
4 In order 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 2018, 97.4% of perinatal deaths were certified by a doctor, with the remaining 2.6% certified by a coroner.
5 Although there is variation across jurisdictions in what constitutes a death that is reportable to a coroner, they are generally reported in circumstances such as:
- where the person died unexpectedly and the cause of death is unknown
- where the person died in a violent or unnatural manner
- where the person died during, or as a result of an anaesthetic
- where the person was 'held in care' or in custody immediately before they died
- where the identity of the person who has died is unknown.
6 The registration of deaths is the responsibility of the eight individual state and territory Registrars of Births, Deaths and Marriages. As part of the registration process, information about the cause of death is supplied by the medical practitioner certifying the death 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 Registrars for coding and compilation into aggregate statistics. In addition, the ABS supplements this data with information from the National Coronial Information System (NCIS). The following diagram shows the process undertaken in producing cause of death statistics for Australia.
The diagram below outlines the Australian Cause of Death Statistics System. Each death is certified by either a doctor or coroner and the resultant information is provided to the Australian Bureau of Statistics (ABS) through the Registrar of Births, Deaths and Marriages in each state or territory. Information is also provided via the National Coronial Information System for those deaths certified by a coroner. The ABS processes, codes and validates this information, which is then provided in statistical outputs.
2018 scope and coverage
7 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. However, there can be lags in the registration of deaths with the state or territory registries and so not all deaths are registered in the year that they occur. 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); and
- a date on which the registered death is lodged with the ABS and deemed in scope.
8 With exception to the statistics published by Year of Occurrence section (Data Cube 13), all deaths referred to in this publication relate to the number of deaths registered, not those which actually occurred, in the years shown.
Scope of Causes of Death statistics
9 The scope for each reference year of the death registrations includes:
- deaths registered in the reference year and received by the ABS in the reference year;
- deaths registered in the reference year and received by the ABS in the first quarter of the subsequent year; and
- deaths registered in the years prior to the reference year but not received by ABS until the reference year or the first quarter of the subsequent year, provided that these records have not been included in any statistics from earlier periods.
10 From 2007 onwards, data for a particular reference year includes all deaths registered in Australia for the reference year that are received by the ABS by the end of the March quarter of the subsequent year. Death records received by the ABS during the March quarter of 2019 which were initially registered in 2018 (but for which registration was not fully completed until 2019) were assigned to the 2018 reference year. Any registrations relating to 2018 which were received by the ABS from April 2019 will be assigned to the 2019 reference year. Approximately 4% to 7% of deaths occurring in one year are not registered until the following year or later.
11 Prior to 2007, the scope for the reference year of the Death Registrations collection included:
- deaths registered in the reference year and received by the ABS in the reference year;
- deaths registered in the reference year and received by the ABS in the first quarter of the subsequent year; and
- deaths registered during the two years prior to the reference year but not received by the ABS until the reference year.
Coverage of Causes of Death statistics
12 The ABS Causes of Death collection includes all deaths that occurred and were registered in Australia, including deaths of persons whose usual residence is overseas. Deaths of Australian residents that occurred outside Australia may be registered by individual Registrars, but are not included in ABS deaths or causes of death statistics.
13 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 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.
14 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 State 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; and
- deaths that occurred in earlier reference periods that have not been previously registered (late registrations).
15 The scope of the statistics excludes:
- repatriation of human remains where the death occurred overseas;
- deaths overseas of foreign diplomatic staff (where these are able to be identified);
- stillbirths/fetal deaths (these are included in perinatal counts (see Explanatory Notes 16-20, below). In 2007-2009 these were published separately in Perinatal Deaths, Australia (cat. no. 3304.0), but are now included in this publication.
Scope of perinatal death statistics
16 The scope of the perinatal death statistics includes all registered fetal deaths (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 fetal deaths are consistent with the legislated requirement for all state and territory Registrars of Births, Deaths and Marriages to register all fetal deaths 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 less and birth weight of 399 grams or fewer). This scope was adopted for the 2007 Perinatal Deaths collection, and was applied to historical data for 1999-2006. For more information on the changes in scope rules see Perinatal Deaths, Australia, 2007 (cat. no. 3304.0) Explanatory Notes 18-20. These rules have been applied to all perinatal data presented in this publication.
17 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, or body length of 25 centimetres from crown to heel. A summary table based on the WHO definition of perinatal deaths is included in the perinatal data cube in this release. See Explanatory Note 81, below, for more details on the interpretation of this table for 2018.
18 Fetal deaths are registered only as a stillbirth, and are not in scope of either the Births, Australia (cat. no. 3301.0) or Deaths, Australia (cat. no. 3302.0) collections. Fetal deaths are part of the Perinatal collection, but not the Causes of Death collection. Neonatal deaths are in scope of the Deaths, Causes of Death and Perinatal collections.
19 This publication only includes information on registered fetal and neonatal deaths. Registered deaths are sourced through jurisdictional Registries of Births Deaths and Marriages (see Explanatory note 6). This scope differs from other Australian data sources on perinatal deaths. For this reason alternative datasets are not directly comparable and caution should be taken when using multiple sources for analysis.
20 Perinatal death data reported by the ABS are not comparable with the National Perinatal Mortality Data Collection (NPMDC) coordinated by the AIHW. As outlined in Explanatory note 19 the ABS data are sourced from state and territory registrars of Births, Deaths and Marriages. This differs from the NPMDC whose data are sourced from health systems, including clinical records. The table below was published in the AIHW Stillbirths and neonatal deaths in Australia 2015 and 2016 report . The table 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.
Number of perinatal deaths reported by Australian Bureau of Statistics (ABS) and the National Perinatal Mortality Data Collection (NPMDC) by Year of Death, Australia, 2013–2016 (Sourced from AIHW, NPMDC, 2018)
NPMDC Neonatal deaths
ABS Neonatal deaths
21 A range of socio-demographic data are available from the ABS Causes of Death collection. Standard classifications used in the presentation of causes of death statistics include age, sex, and Aboriginal and Torres Strait Islander status. Statistical standards for social and demographic variables have been 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.
22 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, causes of death statistics are coded to Statistical Area 2 (SA2) level, and are presented at the state/territory and national level in this publication.
23 The Standard Australian Classification of Countries (SACC) groups neighbouring countries into progressively broader geographic areas on the basis of their similarity in terms of social, cultural, economic and political characteristics. ABS causes of death statistics are coded using the SACC, as the collection includes overseas residents whose death occurred while they were in Australia.
24 For further information, refer to the Australian Statistical Geography Standard (ASGS): Volume 1 - Main Structure and Greater Capital City Statistical Areas, July 2016 (cat. no. 1270.0.55.001) and the Standard Australian Classification of Countries (SACC), 2011 (cat. no. 1269.0).
International Classification of Diseases (ICD)
25 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.
26 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; and
27 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.
28 For further information about the ICD refer to WHO International Classification of Diseases (ICD).
29 The versions of the ICD 10th Revision are available online.
Updates to ICD-10
30 The Update and Revision Committee (URC), a WHO advisory group on updates to ICD-10, maintains the cumulative and annual lists of approved updates to the ICD-10 classification. The updates to ICD-10 are of numerous types including the addition and deletion of codes, changes to coding instructions and modification and clarification of terms.
31 From the 2013 reference year, the ABS implemented a new automated coding system called Iris. The 2013-2017 data coded in the Iris system applied an updated version of the ICD-10 (2013 version for 2013 data, and 2015 version for 2014-2017 data) when coding multiple causes of death, and when selecting the underlying cause of death. For details of further impacts of this change from 2013 data onwards, please see the ABS Implementation of the Iris Software: Understanding Coding and Process Improvements Technical Note, in the Causes of Death, Australia, 2013 (cat. no. 3303.0) publication.
32 The 2018 reference year cause of death data presented in this publication was coded using version 5.4.0 of Iris software. This system replaced Iris version 4.4.1 which was used to code the 2013-2017 cause of death data. Version 5.4.0 of the Iris software applied the WHO ICD updates (2016 version) which have resulted in changes to output. For more information see Technical Note Updates to Iris coding software: Implementing WHO updates and improvements in coding processes, in the Causes of Death, Australia, 2018 (cat. no. 3303.0) publication.
33 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.
34 The cumulative list of ICD-10 updates can be found online.
2013 - 2018 mortality coding
35 From the 2013 reference year onwards, the cause of death data presented in this publication was coded using the Iris coding software. This system replaced the Mortality Medical Data System (MMDS), which was used for coding cause of death data for the 1997-2012 reference years. Like MMDS, Iris is an automated coding system. Iris assigns ICD-10 codes to the diseases and conditions listed on the death certificate and then applies decision tables to select the underlying cause of death. Iris version 4.4.1 was used to code 2013-2017 deaths data. Iris version 5.4.0 was used to code 2018 data. For further details on the change to Iris coding software and associated impacts on data, please see the ABS Implementation of the Iris Software: Understanding Coding and Process Improvements Technical Note, in the Causes of Death, Australia, 2013 (cat. no. 3303.0) publication and Technical Note Updates to Iris coding software: Implementing WHO updates and improvements in coding processes, in the Causes of Death, Australia, 2018 (cat. no. 3303.0) publication.
Types of death
36 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).
External Causes of Death
37 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.
Leading Causes of Death
38 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.
39 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.
40 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 (cat. no. 3303.0). 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. Time-series data by leading causes has been published in Australia's leading causes of death, 2017 in this publication.
41 The ABS now 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 datacubes 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. Time-series data by leading causes has been published in Australia's leading causes of death, 2017 in this publication.
Years of Potential Life Lost (YPLL)
42 Years of Potential Life Lost (YPLL) measures the extent of 'premature' mortality, which is assumed to be any death between the ages of 1-78 years inclusive, and aids in assessing the significance of specific diseases or trauma as a cause of premature death.
43 Estimates of YPLL are calculated for deaths of persons aged 1-78 years based on the assumption that deaths occurring at these ages are premature. The inclusion of deaths under one year would bias the YPLL calculation because of the relatively high mortality rate for that age, and 79 years was the median age at death when this series of YPLL was calculated using 2001 as the standard year. As shown below, the calculation uses the current ABS standard population of all persons in the Australian population at 30 June 2001.
44 YPLL is derived from: where: = adjusted age at death. As age at death is only available in completed years the midpoint of the reported age is chosen (e.g. age at death 34 years was adjusted to 34.5). = registered number of deaths at age due to a particular cause of death. YPLL is directly standardised for age using the following formula: where the age correction factor is defined for age as: where: = estimated number of persons resident in Australia aged 1-78 years at 30 June 2018 = estimated number of persons resident in Australia aged years at 30 June 2018 = estimated number of persons resident in Australia aged years at 30 June 2001 (standard population) = estimated number of persons resident in Australia aged 1-78 years at 30 June 2001 (standard population).
45 The data cubes contain directly standardised death rates and YPLL for males, females and persons. In some cases the summation of the results for males and females will not equate to persons. The reason for this is that different standardisation factors are applied separately for males, females and persons.
Standardised Death Rates
46 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. However, there have been inconsistencies in the way different government agencies have calculated age-standardised death rates in the past. 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.
47 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 a total of 20 deaths have not been published due to issues of robustness.
48 For further information, see Appendix: Principles on the use of direct age-standardisation, from Deaths, Australia, 2010 (cat. no. 3302.0).
49 In this publication, age-standardised and age-specific death rates for Aboriginal and Torres Strait Islander persons for the 2009-2018 reference years have been calculated using 2016-Census-based population estimates (projections and backcasts). Non-Indigenous estimates have been derived by subtracting the 2016-census based Aboriginal and Torres Strait Island population estimates from the total 2016-Census-based estimated resident population (ERP). Rates calculated from population denominators derived from different Censuses may cause artificially large rate differences. Rate comparisons should not be made with previous publications for Aboriginal and Torres Islander data. See Estimates and Projections, Aboriginal and Torres Strait Islander Australians (cat. no. 3238.0) for more information.
State and Territory Data
50 Causes of death statistics for states and territories in this publication 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.
51 Statistics compiled on a state or territory of registration basis are available on request.
Perinatal State and Territory Data
52 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 have been aggregated for South Australia, Western Australia, Northern Territory, Australian Capital Territory and Other Territories.
53 In compiling causes of death statistics, the ABS employs a variety of measures to improve quality, which include:
- providing certifiers with certification booklets for guidance in reporting causes of death on medical certificates, see Information Paper: Cause of Death Certification Australia, 2008 (cat. no. 1205.0.55.001);
- seeking detailed information from the National Coronial Information System (NCIS); and
- editing checks at the individual record and aggregate levels.
54 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).
55 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. Generally most deaths due to external causes will be referred to a coroner for investigation; this includes those deaths which are possible instances of intentional self-harm (suicide).
56 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.
57 The specificity with which open cases are able to be coded is directly related to 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. There may also be interim findings of 'intent'.
58 The manner or intent of an injury which leads to death, is determined by whether the injury was inflicted purposefully or not. When it 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.
Revisions process and other quality improvements
59 These published outputs include 2018 and 2017 preliminary data, 2016 revised data and 2015 final data. The standard ABS revisions process has not yet been applied to the 2016 and 2017 reference years that would, in the past, be subject to revisions in this publication. Causes of death revisions data will be released in early 2020.
60 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.
61 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.
62 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 use of this additional information occurs at either 12 or 24 months after initial processing and the specificity of the assigned ICD-10 codes increase over time. As 12 or 24 months pass after initial processing, many coronial cases are closed, with the coroner having dispensed a cause of death and relevant reports become available. This allows ABS coders to assign a more specific cause of death.
Deaths of Aboriginal and Torres Strait Islander persons
63 The Aboriginal and Torres Strait Islander status of a deceased person is captured through the death registration process. It can be noted on the Death Registration Form and/or the Medical Certificate of Cause of Death. However it is recognised that not all such deaths are captured through these processes, leading to under-identification. While data is provided to the ABS for the Aboriginal and Torres Strait Islander status question for around 99% of all deaths, there are concerns regarding the accuracy of the data.
64 The ABS Death Registrations collection identifies 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 Death Registration Form (DRF). The Indigenous status is also derived from the Medical Certificate of Cause of Death (MCCD) for South Australia, Western Australia, Tasmania, the Northern Territory and the Australian Capital Territory from 2007. From 2015 data onwards, the Queensland Registry of Births, Deaths and Marriages also used MCCD information to derive Indigenous status. For New South Wales and Victoria, the Indigenous status of the deceased is derived from the DRF only. If the Indigenous status reported in the DRF does not agree with that in the MCCD, an identification from either source that the deceased was an Aboriginal and/or Torres Strait Islander person is given preference over non-Indigenous.
65 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.
66 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; and
- cultural aspects and feelings associated with identifying as Aboriginal and Torres Strait Islander Australian.
67 In addition to those deaths where the deceased is identified as an Aboriginal and Torres Strait Islander person, a number of deaths occur each year for which the Indigenous status is not stated on the death registration form. In 2018, there were 1062 deaths registered in Australia for whom Indigenous status was not stated, representing 0.7% of all deaths registered, representing a slight increase from 2017 (0.6%). This difference is largely driven by a higher number of deaths with a not stated Indigenous status registered in New South Wales (from 600 in 2017 to 731 in 2018), and Victoria (from 144 in 2017 to 173 in 2018). All other states experienced a decrease in deaths where indigenous status was not stated representing an improvement in the dataset. See Explanatory Note 63-66 for further details.
68 Data presented in this publication may therefore underestimate the level of Aboriginal and Torres Strait Islander deaths and mortality in Australia. 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.
69 Information on causes of death relating to Aboriginal and Torres Strait Islander persons is included in articles throughout this publication. Data cube 12 also provides information on causes of death for Aboriginal and Torres Strait Islander Australians. In data cube 12, numbers and rates of death are reported by jurisdiction of usual residence for New South Wales, Queensland, South Australia, Western Australia and the Northern Territory only. Data for Victoria, Tasmania and the Australian Capital Territory have been excluded in line with national reporting guidelines. For information on issues with Aboriginal and Torres Strait Islander identification, see Explanatory Notes 63-75.
70 Individual state/territory disaggregations of deaths of Aboriginal and Torres Strait Islander Australians by WHO Leading Causes (see Explanatory Notes 38-41) for the 2018 reference year are presented for New South Wales, Queensland, Western Australia and the Northern Territory only. No data are presented for South Australia, due to the small number of deaths by WHO leading causes - most causes have a count of fewer than 20 deaths, which is too small for the production of robust Standardised Death Rates (SDRs). See Explanatory Notes 46-49 for further details.
71 In this publication, age-standardised and age-specific death rates for Aboriginal and Torres Strait Islander persons for the 2009-2018 reference years have been calculated using 2016-Census-based population estimates (projections and backcasts). Non-Indigenous estimates have been derived by subtracting the 2016-census based Aboriginal and Torres Strait Island population estimates from the total 2016-Census-based estimated resident population (ERP). Rates calculated from population denominators derived from different Censuses may cause artificially large rate differences. Rate comparisons should not be made with previous publications for Aboriginal and Torres Islander data. See Estimates and Projections, Aboriginal and Torres Strait Islander Australians (cat. no. 3238.0) for more information.
72 Coronial cases are more likely to be affected by a lag in registration time, especially those which are due to external causes, including suicide, homicide and drug-induced deaths. Due to small numbers these lagged coroner-referred registrations can create large yearly variation in some causes of deaths of Aboriginal and Torres Strait Islander persons. Caution should be taken when making year to year analysis.
73 The ABS undertakes significant work aimed at improving Aboriginal and Torres Strait Islander identification. The ABS is working closely with the state and territory registries of births, deaths and marriages through the National Civil Registration and Statistics Improvement Committee (NCRSIC) to progress towards improved identification in a nationally consistent way.
74 Quality studies conducted as part of the Census Data Enhancement (CDE) project have investigated the levels and consistency of Aboriginal and Torres Strait Islander identification between the 2011 Census and death registrations. See Information Paper: Death registrations to Census linkage project - Methodology and Quality Assessment, 2011-2012 (cat. no. 3302.0.55.004).
75 An assessment of various methods for adjusting incomplete Aboriginal and Torres Strait Islander death registration data for use in compiling Aboriginal and Torres Strait Islander life tables and life expectancy estimates is presented in Discussion Paper: Assessment of Methods for Developing Life Tables for Aboriginal and Torres Strait Islander Australians, 2006 (cat. no. 3302.0.55.002), released on 17 November 2008. Final tables based on feedback received from this discussion paper, using information from the Census Data Enhancement (CDE) study, can be found in Life Tables for Aboriginal and Torres Strait Islander Australians, 2010-2012 (cat. no. 3302.0.55.003).
Deaths by type of certifier
76 For deaths in the 2018 reference year, 11.9% were certified by a coroner. There are variations between jurisdictions in relation to the proportion of deaths certified by a coroner, ranging from 8.2% of deaths certified by a coroner and registered in Queensland, to 26.1% of deaths certified by a coroner and registered in the Northern Territory. The proportion of deaths certified by a coroner in 2018 is comparable to previous years.
Issues to be considered when interpreting time-series and 2018 data
77 The 2018 publication has followed the same process of publication as the 2017 data. The 2017 publication was released six months earlier than usual, allowing for more timely access to mortality data in Australia. For further details on data considerations, see A more timely annual collection: changes to ABS processes (Technical Note), Causes of Death, Australia, 2015 (cat. no. 3303.0).
Use of Iris as a new auto-coding system and implementation of updates to ICD-10
78 From the 2013 reference year onwards, the cause of death data presented in this publication was coded using the Iris coding software. This system replaced the Mortality Medical Data System (MMDS), which was used for coding cause of death data for the 1997-2012 reference years. Like MMDS, Iris is an automated coding system. Iris assigns ICD-10 codes to the diseases and conditions listed on the death certificate and then applies decision tables to select the underlying cause of death. Iris version 4.4.1 was used to code 2013-2017 deaths data. Iris version 5.4.0 was used to code 2018 data. For further details on the change to Iris coding software and associated impacts on data, please see the ABS Implementation of the Iris Software: Understanding Coding and Process Improvements Technical Note, in the Causes of Death, Australia, 2013 (cat. no. 3303.0) publication and Technical Note Updates to Iris coding software: Implementing WHO updates and improvements in coding processes, in the Causes of Death, Australia, 2018 (cat. no. 3303.0) publication.
79 Users analysing time-series or 2018 cause of death data should take into account a number of issues, as outlined below, which are unrelated to the implementation of Iris.
Coding of perinatal deaths
80 For perinatal data output in the Causes of Death, Australia, 2013 publication, the ABS began a review of its method of coding perinatal deaths, which resulted in an interim change to how this data was output. One significant change was that neonatal deaths were not assigned an underlying cause of death when output in tables of all ages, as had previously occurred. (Details of this change can be found in the Changes to Perinatal Death Coding Technical Note in Causes of Death, Australia, 2013 (cat. no. 3303.0). Further review and consultation has now been undertaken with the national and international coding community, and has resulted in the ABS applying a new method of coding perinatal deaths. 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 the output for neonatal deaths to deaths of the general population which are certified using the Medical Certificate of Cause of Death. The change in coding method reinstates the condition arising in the mother being assigned as an underlying cause of death. This method has been applied to the 2014-2018 data, and has also been applied retrospectively to the 2013 neonatal data that is output in tables of all ages in this publication, thus enabling a consistent time-series. Please see the Changes to Perinatal Death Coding Technical Note in Causes of Death, Australia, 2014 (cat. no. 3303.0) for further details.
81 From the 2013 reference year onwards, process changes have led to a reduction in the number of both stillbirths and neonatal deaths where a 'main condition in mother' was recorded, compared to previous years. This has led to a reduction in the number of records 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 will affect data output in the Perinatal data cube of this publication only.
82 Doctor-certified neonatal deaths with no cause 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 cause 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.
83 The count of fetal deaths in scope for the World Health Organization (WHO) definition of perinatal deaths differs to those previously published for 2012 and 2015. This is due to an enhancement to birth weight and gestation information, which resulted in some deaths no longer meeting the World Health Organization definition of a fetal death (that is, a gestational age of at least 22 weeks or weighing at least 500 grams). For 2012, there are two fewer fetal deaths than previously published (1 male and 1 female). For 2015, there are 38 fewer fetal deaths than previously published (18 males, 19 females, 1 death of undetermined sex). Some corresponding death rates have also been affected. Table 14.21 in the perinatal data cube presents fetal and neonatal data according to the WHO scope. No other tables in the perinatal deaths data cube are affected by these changes.
Increased number of deaths, New South Wales
84 In September quarter 2011 the high number of death registrations in New South Wales was queried with the New South Wales Registry of Births, Deaths and Marriages. Information provided by the Registry indicates that these fluctuations may be the result of changes in processing rates. This may have contributed to the increase in the number of deaths registered in New South Wales in 2011. New South Wales deaths in 2011 (50,182) were 5.8% higher than in 2010 (47,453).
Accident to watercraft causing drowning and submersion (V90)
85 The number of deaths attributable to Accident to watercraft causing drowning and submersion (V90) increased from 26 in 2010 to 75 in 2011. This increase is primarily due to deaths resulting from an incident in December 2010 when a boat collided with cliffs on Christmas Island. These deaths were registered with the Western Australian Registry of Births, Deaths and Marriages in January 2011, resulting in an increase in the number of deaths coded to V90 in Western Australia.
Pneumonia, organism unspecified (J18)
86 As part of a collection-wide initiative by the ABS to improve specificity of cause of death coding in the 2008 and 2009 reference years, doctor-certified deaths due to Pneumonia, organism unspecified (J18) reduced substantially. This was as a result of the ABS manually interrogating conditions located in Part 2 of the Medical Certificate Cause of Death (MCCD), reallocating them to a more specific cause of death code.
87 In 2010 there was a shift in this pattern. The number of doctor-certified deaths assigned to J18 increased by 690 deaths, or 49.5%. The reason for the 2010 data movement was a more consistent use of coding software decision tables throughout both coding and quality assurance processes. These decision tables provide clear rules for when Pneumonia can be selected as an underlying cause of death, in relation to the information listed in Part 2 of the MCCD.
88 The 2010 increase represented a return to counts observed prior to 2008. In 2007, 2,293 doctor certified deaths were assigned to J18, therefore the 2010 count for this cause of death (2,085) is considered a return to the trend which existed prior to the coding of 2008 and 2009 data. The data from 2011 onwards has been consistent with this trend.
Transport Accidents (V01-V79, Y32)
89 There were 1,273 deaths attributed to road crashes (V01-V79, V892, X82, Y32) in 2018. Of these, 37 were of suicidal intent (X82) and there were a further 16 where the intent could not be determined (Y32). 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 2018 is expected to change as data is subject to the revisions process. See Explanatory Notes 59-62 and the Causes of Death Revisions, 2015 Final Data (Technical Note) in Causes of Death, Australia, 2017 for further details.
Assault (X85-Y09, Y87.1)
90 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, 2017 (cat. no. 4510.0). 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 2018 is expected to change as data is subject to the revisions process. See Explanatory Notes 59-62 and Causes of Death Revisions, 2015 Final Data (Technical Note) and 2016 Revised Data (Technical Note) in Causes of Death, Australia, 2017 (cat. no. 3303.0).
Intentional Self-Harm (Suicide) (X60-X84, Y87.0)
91 The number of deaths attributed to intentional self-harm for 2018 is expected to increase as data is subject to the revisions process. For further information, see Explanatory Notes 59-62 and the Causes of Death Revisions, 2015 Final Data (Technical Note) and 2016 Revised Data (Technical Note) in Causes of Death, Australia, 2017 (cat. no. 3303.0).
92 From 2006 onwards, the ABS implemented a revisions process for coroner-certified deaths (such as suicides), which has enabled additional suicide deaths to be identified beyond initial processing (see Explanatory Notes 54-62). It is recognised that in the four years prior to the implementation of the revisions process (2002-2005), 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.
93 In addition to the revisions process, new coding guidelines were applied for deaths registered from 1 January 2007. The new guidelines improve data quality by enabling deaths to be coded to suicide if evidence indicates the death was from intentional self-harm. Previously, coding rules required a coroner to determine a death as intentional self-harm for it to be coded to suicide. However, in some instances the coroner does not make a finding on intent. The reasons for this may include legislative or regulatory barriers around the requirement to determine intent, or sensitivity to the feelings, cultural practices and religious beliefs of the family of the deceased. Further, for some mechanisms of death it may be very difficult to determine suicidal intent (e.g. single vehicle incidents, drowning). In these cases the burden of proof required for the coroner to establish that the death was as a result of intentional self-harm may make a finding of suicide less likely.
94 Under the new coding guidelines, in addition to coroner-determined suicides, deaths may also be coded to suicide following further investigation of information on the NCIS. Further investigation of a death would be initiated when the mechanism of death indicates a possible suicide and the coroner does not specifically state the intent as accidental or homicidal. Information that would support a determination of 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. The processes for coding open and closed coroner cases are illustrated in the below diagrams (open/closed case coding decision trees).
95 Over time, the NCIS has worked with jurisdictions to improve the timeliness and completeness of information flowing from the coronial systems to the NCIS database. These improvements lead to changes in the information available to ABS coding staff. It is therefore important that data users are aware of any significant improvements in the management of coronial data to enable better interpretation of data within, and between, reference periods.
96 In 2012, the implementation of JusticeLink in the NSW coronial system significantly changed how information is exchanged between the NSW coroners courts and the NCIS. This system enables nightly uploads of all new information to the NCIS, and as a result information pertaining to NSW coronial cases is available earlier in the investigation process and the information is more complete for the purposes of coding causes of death.
97 There is evidence that the system change in NSW has improved the quality of preliminary coding in relation to deaths due to intentional self-harm. There has been an increase in the number of preliminary intentional self-harm deaths registered in NSW when comparing 2012-2017 counts (708, 694, 798, 819, 799 and 881, respectively) with those of 2011 (568), coupled with fewer cases of deaths of undetermined intent (Y10-Y34).
98 Coronial cases are more likely to be affected by a lag in registration time, especially those which are due to external causes, including suicide, homicide and drug-related deaths. Due to small numbers these lagged coroner-referred registrations can create large yearly variation in some causes of deaths of Aboriginal and Torres Strait Islander persons. Caution should be taken when making year to year analysis.
99 More broadly, change in administrative systems highlights how various factors (including administrative and system changes, certification practices, classification updates or coding rule changes) can impact on the mortality dataset. Data users should note this particular change and be cautious when making comparisons between reference periods. The change does not explain away differences between years, but is a factor to consider. It should also be noted as a factor that may influence the magnitude of any increases in suicide numbers as revisions are applied.
100 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.
Registration of Outstanding Deaths, Queensland
101 In November 2010, the Queensland Registrar of Births, Deaths and Marriages advised the ABS of an outstanding deaths registration initiative undertaken by the registry. This initiative resulted in the November 2010 registration of 374 previously unregistered deaths which occurred between 1992 and 2006 (including a few for which a date of death was unknown). Of these, around three-quarters (284) were deaths of Aboriginal and Torres Strait Islander Australians. A data adjustment is made for tables which include Aboriginal and Torres Strait Islander data for Queensland for 2010. For further information refer to Technical Notes, Registration of Outstanding Deaths, Queensland, 2010 in Deaths, Australia, 2010 (cat. no. 3302.0) and Retrospective Deaths by Causes of Death, Queensland, 2010, in Causes of Death, Australia, 2010 (cat. no. 3303.0).
102 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 fetal, neonatal and perinatal death rates shown in this publication. This Appendix also provides data on fetal deaths used in the calculation of fetal and perinatal death rates. These also enable further rates to be calculated.
103 In 2016 the NSW Registry changed the 'proof of identity' requirements for parents registering a new birth. This led to delays in registration of births for 2016 and 2017. The ABS has been working with the NSW Registry to improve the birth registration lag, The recent launch of online birth registration in 2018 by the NSW Registry appears to be improving birth registration time frames for both Aboriginal and Torres Strait Islander and non-Indigenous Australians.
104 In 2016 and 2017 there were lower than expected 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 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.
105 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 and fertility rates for the Northern Territory in recent years.
Use of Multiple Cause of Death data
106 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 cause 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 cause of death data provide a more in depth picture of mortality in Australia.
107 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 Cause 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 cause of death data.
108 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. 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. For example, in 2009, the World Health Organization (WHO) recommended introducing code J09 (Influenza due to certain identified influenza virus) to the ICD-10 in response to the worldwide epidemics of swine flu and avian flu. There were 98 people who died as a direct consequence of contracting these strains of the flu across 2009 and 2010. In addition there were 51 people who had this flu when they died and for whom this would have been a complicating factor. Additional health risk factors may also be identified. When swine or avian flu was the underlying cause of death, multiple cause data shows obesity and respiratory problems as a common associated cause. In this way, multiple cause data provides policy makers and researchers a greater insight beyond the underlying cause of death.
Confidentialisation of data
109 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.
Effects of rounding
110 Where figures have been rounded, discrepancies may occur between totals and sums of the component items.
111 The Victorian Registry of Births, Deaths and Marriages (RBDM) implemented a new registration system in February 2019. As part of this system implementation, certain policies and procedures have changed within the registry. Of note, the Victorian RBDM has changed their procedures regarding the registration of coroner-referred deaths. Previously coroner-certified deaths were not submitted to the ABS until the case was finalised in the Victorian Coroner Court. From 2019, this has changed and interim registrations (open cases) have been submitted to the ABS. This procedural change has resulted in an additional delay to registrations in 2018 and previous years, but the change to procedure is expected to lead to an increased number of coroner-referred registrations in 2019.
112 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.