Geulayov, Galit et al. The Lancet Psychiatry , Published online December 2017

This review of UK data demonstrates the challenges of clinical risk assessment.  For every 12-14 year old boy that died by suicide, 109 attended hospital with self-harm and 3067 reported self-harm in the community.  For every 12-14 year old girl who died by suicide, 1255 attended hospital for self-harm and 21,995 reported self-harm in the community.  For every 15-17 year old male who died by suicide, 120 presented to hospital with self-harm and 838 reported self-harm in the community. For every 15-17 year old girl who died by suicide, 919 presented to hospital with self-harm and 6406 reported self-harm in the community.

http://www.thelancet.com/journals/lanpsy/article/PIIS2215-0366(17)30478-9/fulltext