The iceberg model of self-harm
Researchers have created a model of self-harm that shows high levels of the problem in the community, especially in young girls, and the need for school-based prevention measures.
The team from the University of Oxford used national data on suicide, together with data on hospital-presenting self-harm from five hospitals and data on self-harm in the community from a large-scale schools survey to estimate the relative incidence of fatal and non-fatal self-harm in 12–17 year-olds adolescents in England and described these in terms of an iceberg model including: fatal self-harm i.e. suicide, an overt but uncommon behaviour (the tip of the iceberg); self-harm that results in presentation to clinical services, especially general hospitals, which is also overt, but common; and self-harm that occurs in the community, which is common but largely hidden (the submerged part of the iceberg).
Estimated rates of fatal and non-fatal self-harm showed that for every adolescent who died by suicide, there were approximately 370 adolescents who presented to hospital for self-harm and 3,900 adolescents who reported self-harm in the community. These figures suggest that every year in England, about 21,000 adolescents aged 12–17 years present to hospital following self-harm and 200,000 self-harm in the community and do not present to hospital. The investigators further showed that while the incidence of suicide in adolescent males was twice that of females, the incidences of both hospital-presenting and community-occurring non-fatal self-harm were substantially higher in females than in males. Notably, the incidence of self-harm occurring in the community in younger adolescents (12-14 year-olds) was as high as that found for older adolescents (15-17 year-olds), the age at which self-harm is thought to peak.
The findings of this study, which was led by Professor Keith Hawton and Dr Galit Geulayov from the Centre for Suicide Research, are published in The Lancet Psychiatry.
"Our findings confirm that there are very high levels of self-harm in adolescents. While large numbers of adolescents present to hospital following self-harm, there are many more adolescents who self-harm in the community and do not come to the attention of clinicians," said Professor Hawton. He added: "It is clearly a particular problem in females and very young adolescents. This shows the need not only for good quality and responsive clinical services, but also for effective internet-based interventions and especially prevention at the community level, particularly through school-based initiatives."
In adolescents, non-fatal self-harm is a common reason for hospital presentation and also occurs frequently in the community without coming to clinical attention. Suicide is a leading cause of death in adolescents and is often preceded by self-harm.
Self-harm and suicide in children and adolescents have been highlighted as a key area for intervention and prevention by the National Suicide Prevention Strategy for England. This is the first study to explore the relative sizes of the populations of adolescents involved in these three levels of self-harm in England.
The full report, "Incidence of suicide, hospital-presenting non-fatal self-harm, and community-occurring non-fatal self-harm in adolescents in England (the iceberg model of self-harm): a retrospective study," is published in The Lancet Psychiatry.