Policy on the prevention of suicidal behaviour; one treatment for all may be an unrealistic expectation.

In the absence of clear guidelines on suicide prevention there is a pressing need to translate existing and future evidence into policy. Suicide is a behaviour, not a diagnosis, and has diverse underlying pathologies. Interventions have differential effects in specific risk groups, which may include paradoxical increases in risk. For these reasons, policy makers may need to abandon the goal of one treatment for all and focus on the distinct subgroups of patients at risk when selecting, evaluating and implementing preventive interventions. This has implications for the design of future research, but has the potential to increase the utility and cost-effectiveness of the data available, thereby benefiting policy makers, clinicians and patients.