Disclosure of suicidal ideation and behaviours: A systematic review and meta-analysis of prevalence*

Disclosure of suicidal ideation and behaviours, defined as thoughts, plans, or attempts, to other people provides opportunity for intervention and prevention. This study is the first to meta-analyze all available studies to es-timate the prevalence of disclosure, to whom people disclose, and examine factors that influence disclosure. Databases were searched for studies reporting samples of people who had experienced suicidal ideation or be-haviours (including those who had died by suicide) and whether they had disclosed this. Almost 100 studies (k = 94, N participants = 1,044,629) were included in the overall prevalance analysis. The results showed less than half of people disclosed suicidal ideation or behaviour: 45.9% (95%CI 41.9-49.9%, PI 12.3-81.8%; k = 94). High heterogeneity, common to prevalence studies, was found (Q[93] = 130,584, p < .001; I2 = 99.9%). No publi-cation bias was detected. Removing outliers did not change the prevalence estimate, but provided tighter pre-diction intervals: 45.6% (95%CI 43.4-47.9%, PI 35.8-55.7%; k = 33). Disclosure was related to higher prevalence of psychiatric disorders, female gender, and a longer timeframe of suicidal ideation or behaviour. Prevalence of disclosure was lower among people who died by suicide, relative to community samples, and lower when reported verbally rather than written online. Disclosure, and proportions of disclosures, to family members, was numerically higher than to friends or professionals, but could not be directly compared. In conclusion, between 50 and 60% of people do not disclose their suicidal ideation and behaviours to other people, and therefore remain unidentified and potentially untreated.