Is the reported increase in young female hospital-treated intentional self-harm real or artefactual?

Katie McGill; Sarah A Hiles; Tonelle E Handley; Andrew Page; Terry J Lewin; Ian Whyte; Gregory L Carter

doi:10.1177/0004867418815977

Is the reported increase in young female hospital-treated intentional self-harm real or artefactual?

Aust N Z J Psychiatry. 2019 Jul;53(7):663-672. doi: 10.1177/0004867418815977. Epub 2018 Dec 5.

Authors

Katie McGill^{1

2}, Sarah A Hiles³, Tonelle E Handley^{1

4}, Andrew Page⁵, Terry J Lewin^{1

2}, Ian Whyte^{1

6

7}, Gregory L Carter^{1

8}

Affiliations

¹ 1 School of Medicine and Public Health, Faculty of Health and Medicine, University of Newcastle, Callaghan, NSW, Australia.
² 2 MH-READ, Hunter New England Local Health District, Newcastle, NSW, Australia.
³ 3 School of Nursing and Midwifery, Faculty of Health and Medicine, University of Newcastle, Callaghan, NSW, Australia.
⁴ 4 Centre for Rural and Remote Mental Health, University of Newcastle, Callaghan, NSW, Australia.
⁵ 5 Translational Health Research Institute, Western Sydney University, Penrith, NSW, Australia.
⁶ 6 Discipline of Clinical Pharmacology and Toxicology, University of Newcastle, Callaghan, NSW, Australia.
⁷ 7 Department of Clinical Pharmacology and Toxicology, Calvary Mater Newcastle, Waratah, NSW, Australia.
⁸ 8 Department of Consultation Liaison Psychiatry, Calvary Mater Newcastle, Waratah, NSW, Australia.

PMID: 30518227
DOI: 10.1177/0004867418815977

Abstract

Background: The Australian Institute of Health and Welfare has reported an increased rate of hospital-treated intentional self-harm in young females (2000-2012) in Australia. These reported increases arise from institutional data that are acknowledged to underestimate the true rate, although the degree of underestimation is not known.

Objective: To consider whether the reported increase in young females' hospital-treated intentional self-harm is real or artefactual and specify the degree of institutional underestimation.

Methods: Averages for age- and gender-standardised event rates for hospital-treated intentional self-harm (national: Australian Institute of Health and Welfare; state: New South Wales Ministry of Health) were compared with sentinel hospital event rates for intentional self-poisoning (Hunter Area Toxicology Service, Calvary Mater Newcastle) in young people (15-24 years) for the period 2000-2012. A time series analysis of the event rates for the sentinel hospital was conducted.

Results: The sentinel hospital event rates for young females of 444 per 100,000 were higher than the state (378 per 100,000) and national (331 per 100,000) rates. There was little difference in young male event rates - sentinel unit: 166; state: 166 and national: 153 per 100,000. The sentinel hospital rates showed no change over time for either gender.

Conclusion: There was no indication from the sentinel unit data of any increase in rates of intentional self-poisoning for young females. The sentinel and state rates were higher than the national rates, demonstrating the possible magnitude of underestimation of the national data. The reported increases in national rates of hospital-treated self-harm among young females might be due to artefactual factors, such as changes in clinical practice (greater proportion admitted), improved administrative coding of suicidal behaviours or possibly increased hospital presentations of community self-injury cases, but not intentional self-poisoning. A national system of sentinel units is needed for the accurate and timely monitoring of all hospital-treated self-harm.

Keywords: Self-harm; self-poisoning; surveillance.

MeSH terms

Adolescent
Female
Hospitalization / statistics & numerical data*
Humans
Incidence
Male
New South Wales
Population Surveillance
Self-Injurious Behavior / epidemiology*
Sex Factors
Suicide, Attempted / statistics & numerical data*
Young Adult