BACKGROUND: Many countries are developing suicide prevention strategies for which
up-to-date, high-quality evidence is required. We present updated evidence for the
effectiveness of suicide prevention interventions since 2005. METHODS: We searched
PubMed and the Cochrane Library using multiple terms related to suicide prevention
for studies published between Jan 1, 2005, and Dec 31, 2014. We assessed seven interventions:
public and physician education, media strategies, screening, restricting access to
suicide means, treatments, and internet or hotline support. Data were extracted on
primary outcomes of interest, namely suicidal behaviour (suicide, attempt, or ideation),
and intermediate or secondary outcomes (treatment-seeking, identification of at-risk
individuals, antidepressant prescription or use rates, or referrals). 18 suicide prevention
experts from 13 European countries reviewed all articles and rated the strength of
evidence using the Oxford criteria. Because the heterogeneity of populations and methodology
did not permit formal meta-analysis, we present a narrative analysis. FINDINGS: We
identified 1797 studies, including 23 systematic reviews, 12 meta-analyses, 40 randomised
controlled trials (RCTs), 67 cohort trials, and 22 ecological or population-based
investigations. Evidence for restricting access to lethal means in prevention of suicide
has strengthened since 2005, especially with regard to control of analgesics (overall
decrease of 43% since 2005) and hot-spots for suicide by jumping (reduction of 86%
since 2005, 79% to 91%). School-based awareness programmes have been shown to reduce
suicide attempts (odds ratio [OR] 0.45, 95% CI 0.24-0.85; p=0.014) and suicidal ideation
(0.5, 0.27-0.92; p=0.025). The anti-suicidal effects of clozapine and lithium have
been substantiated, but might be less specific than previously thought. Effective
pharmacological and psychological treatments of depression are important in prevention.
Insufficient evidence exists to assess the possible benefits for suicide prevention
of screening in primary care, in general public education and media guidelines. Other
approaches that need further investigation include gatekeeper training, education
of physicians, and internet and helpline support. The paucity of RCTs is a major limitation
in the evaluation of preventive interventions. INTERPRETATION: In the quest for effective
suicide prevention initiatives, no single strategy clearly stands above the others.
Combinations of evidence-based strategies at the individual level and the population
level should be assessed with robust research designs. FUNDING: The Expert Platform
on Mental Health, Focus on Depression, and the European College of Neuropsychopharmacology.
