Background: Self-harm in the UK military has variously been estimated at 1-5.6% compared with 4.9% in the general UK population.
Aims: To establish the overall prevalence of self-harm within the UK military, to establish the association between deployment and self-harm and to identify sociodemographic and social factors associated with self-harm within the UK military.
Methods: A cross-sectional postal survey of UK military personnel.
Results: There were 9803 respondents. The overall prevalence of self-harm was 2.3% in the UK military. Self-harm was not associated with deployment but was significantly associated with being discharged, separated, of lower rank, female and younger age, reporting no close friends or family, reporting fewer social activities, having spent time in local authority care as a child, and having adversity in family relationships as a child.
Conclusions: Contrary to predictions, self-harm in the UK military is not associated with deployment. It is linked to available social support in childhood and adulthood.
Keywords: Armed forces; UK.; military; self-harm.