Background. Reports of adolescent suicidal behaviour have generally de
rived from clinical settings but population-based studies art likely t
o provide a clearer epidemiological view. Methods. Non-fatal suicidal
behaviours were studied in 1699 Australian 15- to 16-year-old secondar
y school students at 44 schools in the state of Victoria, Australia, S
elf-reported episodes of self-harm were characterized using items from
the Beck Suicide Intent Scale. Results. The 12 month weighted prevale
nce estimate for deliberate self-harm was 5.1%. The commonest forms we
re self-laceration (1.7%), self-poisoning (1.5%) and deliberate reckle
ssness (1.8%). Self-poisoning and self-laceration were commoner in gir
ls. The prevalence of 'true suicide attempts' was 0.2%. Most self-harm
ers did not perceive death as likely, plan self-harming episodes at le
ngth or inform others of the episodes. Psychiatric morbidity had the s
trongest association with self-harm, an association which held for all
subtypes. Antisocial behaviour and substance abuse were associated wi
th self-harm in girls but not boys. Sexual activity was independently
associated with self-harm in both genders. Conclusions. Deliberate sel
f-harm was common but the great majority of episodes were not 'true su
icide attempts'. It is, therefore, possible that attributable mortalit
y and morbidity may be greater in self-harmers without definite suicid
al intent.