Data source

Mental health-related emergency department data

All state and territory health authorities collect a core set of nationally comparable information on emergency department (ED) presentations (including mental health-related emergency department presentations) in public hospitals within their jurisdiction. The AIHW compiles this data annually to form the National Non-Admitted Patient Emergency Department Care Database (NNAPEDCD). In 2017–18, 286 of Australia’s public hospital emergency departments reported emergency department presentations to the NNAPEDCD (AIHW 2018).

Previously, diagnosis-related information was not included in the NNAPEDCD, therefore, states and territories provided the AIHW with a bespoke analysis of mental health-related emergency department presentations. Data on principal diagnosis—that is, the diagnosis chiefly responsible for occasioning the presentation to the emergency department—has subsequently been included in the NNAPEDCD. In this report, data from 2014–15 to 2017–18 are sourced from the NNAPEDCD. Data from previous years was sourced directly from jurisdictions through an annual ad-hoc data request.   

Definition of mental health-related emergency department presentations

Mental health-related ED presentations in this report are defined as presentations in public hospital EDs that have a principal diagnosis of Mental and behavioural disorders (that is, codes F00–F99) in ICD-10-AM or the equivalent codes in ICD-9-CM.

For 2017–18, diagnosis information is reported for the NNAPEDCD using the following classifications:

• Systematized Nomenclature of Medicine—Clinical Terms—Australian version, Emergency Department Reference Set (SNOMED CT-AU (EDRS))

• International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) 2nd edition

• International Classification of Diseases and Related Health Problems, 10th Revision, Australian Modification (ICD-10-AM) 6th edition, 7th edition, 8th edition, 9th edition, or 10th edition.

The AIHW undertook to map all diagnosis information to a single classification. Further information on the mapping is available in Appendix B of the AIHW’s Emergency Department Care 2017–18: Australian hospital statistics (AIHW 2018).

The Mental and behavioural disorders principal diagnosis codes may not fully capture all mental health-related presentations to EDs, such as presentations for self-harm. Diagnosis codes for intentional self-harm sit outside the Mental and behavioural disorders chapter (X60-X84). Additionally, a presentation for self-harm may have a principal diagnosis relating to the injury, for example Open wound to wrist and hand. These presentations cannot be identified as mental health-related presentations in the NNAPEDCD and are not included in this report.

Further information on NNAPEDCD is available on METeOR, the AIHW’s Metadata Online Registry.


In 2017–18, 286 of Australia’s public hospital emergency departments reported emergency department presentations to the NNAPEDCD (AIHW 2018).

Presentation of regional data

Data are reported at regional levels for the first time in this report. To report at this level, data were aggregated to SA3 and apportioned to PHN based on correspondence files published by the Australian Bureau of Statistics. This analysis was based on the correspondence files relevant to the specific collection period. For example, for years prior to 2017–18, SA2 data are based on 2011 ASGS and mapped to 2015 PHN boundaries. The 2017–18 SA2 data are based on 2016 ASGS and mapped to 2017 PHN boundaries. Comparisons of the data across time should therefore be approached with caution. Methodological approaches will be reviewed for future publication of emergency department data.


ABS  (Australian Bureau of Statistics) 2018. Estimates of Aboriginal and Torres Strait Islander Australians, June 2016. Cat. No. 3238.0.55.001. Canberra: ABS

AIHW (Australian Institute of Health and Welfare AIHW) 2018. Emergency department care 2017–18: Australian hospital statistics. Health services series no. 89. Cat. no. HSE 216. Canberra: AIHW.

Morphet J, Innes K, Munro I, O'Brien A, Gaskin CJ, Reed F et al. 2012. Managing people with mental health presentations in emergency departments—A service exploration of the issues surrounding responsiveness from a mental health care consumer and carer perspective. Australasian Emergency Nursing Journal 15:148-55.