Notes on measuring suicide rates 2002 to 2018

There are differences between the demographic profiles of the three Australian Defence Force (ADF) service status groups and the Australian population (Box 2). Because of these differences, comparisons of numbers of suicides between the ADF service status groups and the Australian population are not straightforward.

Box 2: Differences between the ADF and Australian populations

Compared with the ADF service status groups, the Australian population is older on average and around 50% male, while the ADF service status groups are younger and around 85% male. These age and sex differences need to be accounted for when examining differences in suicide levels between these populations.

Further, the annual population size for each of the service status groups differs. While the serving and reserve populations are relatively stable over time, the ex-serving population in this study started at zero (0) on 1 January 2001 and increased each year as personnel discharge. Unlike the serving and reserve populations, the ex-serving population is also ageing over time.

To assist in making comparisons, this report presents rates of suicide and Standardised Mortality Ratios (SMRs). Suicide rates contextualise information on the number of deaths by suicide by taking into account the size of the underlying population. SMRs provide an even more meaningful comparison by controlling for the difference in age structures between the three ADF service status groups and its equivalent comparison (Australian) population. SMRs are presented as comparisons of age-adjusted rates.

Data for 2001 are not included in the calculation of rates in this report, as data for the serving and reserve populations were not available before 2002 due to a change in Defence personnel management systems at that time. Analysis of ex-serving personnel was restricted to data from 2002 onwards, in line with reporting for serving and reserve groups. For information on interpreting these results, including changes to previously published data, see Box 2 and the Technical notes.

Confidence Intervals

Confidence intervals are presented in this report to reflect some of the uncertainty in the suicide rates calculated for the three ADF service status groups and the Australian population. Confidence intervals provide one way to assess the uncertainty in estimated rates due to fluctuations that may occur in the number suicides over time. There are other sources of uncertainty, such as linkage error, that are not captured by these intervals.

As time passes and more data become available, greater confidence can be attached to any consistent observed differences in outcomes between the ADF population and the comparable Australian population.

See the Technical notes for more information on confidence intervals.

If you need help or support, please contact:

Open Arms - Veterans and Families Counselling 1800 011 046

Open Arms Suicide Intervention page

ADF All-hours Support Line 1800 628 036

Lifeline 13 11 14

Suicide Call Back Service 1300 659 467

Beyond Blue Support Service 1300 22 4636

For information on support provided by DVA see: