Technical notes


This report counts and describes injury incidents that result in hospital admission and/or death.

Our counting method is different to some other AIHW reporting (such as MyHospitals), where each use of a service may be counted rather than each incident. A single incident can lead to more than one use of a service. Our exclusion method minimises the associated double counting but does not eliminate it.

If a person dies from an injury after being admitted to hospital, both the hospitalisation and the death were counted for this report.

Injury hospitalisations

The terms ‘injury hospitalisation’, ‘hospitalised injury’ and ‘hospitalised case’ in this report refer to incidents where a person was admitted to hospital with injury as the main reason. If a single incident led to an admission in more than one hospital, the incident has only been counted once.


To minimise double-counting hospitalisations for injuries, we have excluded admissions that are transfers from another hospital and admissions with rehabilitation procedures (except for acute hospital admissions).

Emergency department (ED) care is a form of non-admitted hospital care and is not counted here. See the AIHW MyHospitals topic for information on ED presentations due to injury.

Injuries caused by complications of surgery or other medical care, or injuries that are a subsequent condition caused by a previous injury, are not included in this report.

Date of admission versus separation

The seasonal differences figures and tables in this report were based on date of admission data, to approximate the dates of the injuries causing the hospitalisations. All other annual totals were based on year of separation. Separation does not necessarily occur in the same month (or year) as admission. Partly because of this, summing the counts in the seasonal differences tables would produce slightly different numbers than the annual totals. Also, the admission counts were adjusted to suit comparison between months of different length.

Australia’s Health Performance Framework indicators

Australia’s health performance framework allows for the monitoring of a broad range of population health indicators over time, and includes indicators related to rates of injury and poisoning hospitalisation. These are calculated using a scope similar to Injury in Australia, however data have not been backcast with each update. This means that the scope for injury indicator data in a given year may be slightly different to the scope of previous years. See the relevant section below for details.

Injury hospitalisations in Australia, 2021–22: about the data

The Injury in Australia report counts and describes incidents of injury that lead to hospital admission and/or death, classified by cause. This technical document describes the hospital data.

For ease of reading, cases of hospitalisation for injury are referred to in the report as ‘injury hospitalisations’. However, throughout this technical note we have referred to a ‘case’ of hospitalisation for injury. This is to differentiate our count of injury hospitalisations from the more common counting unit for hospital patients which is a ‘separation’ (the end of an episode of care). A single incident of injury may result in multiple consecutive episodes of care, which we count as one ‘case’ of hospitalisation to represent the one incident of injury.

A person may have more than one incident of injury resulting in hospitalisation in a financial year and each case of hospitalisation will be counted separately in this report. This is because we are counting incidents of injury resulting in hospitalisation, rather than the number of people who were hospitalised, in a given financial year.

Injury deaths

While death records have many of the same fields as hospital records, there are subtle differences in the way they are structured.

It is not always possible to determine the main cause of death when multiple causes are involved. For this reason, a different selection criterion must be applied to reasonably identify where injuries played a role. As a result, each death where injury played a role has been counted once in the total for this report, but in some cases counted in more than one injury cause category.

To understand the analysis in more detail, please find below:

  • Injury hospitalisations in Australia, 2021–22: about the data
  • Injury deaths in Australia, 2020–21: about the data
  • Appendix tables specifying the ICD-10 codes used for each cause category

Injury deaths in Australia, 2020–21: about the data