Effectiveness of suicide means restriction: an overview of systematic reviews

Means restriction for suicide prevention at a population level typically involves policy or environmental changes to limit access to suicide methods. Several systematic reviews of suicide means restriction exist. This umbrella review aimed to synthesise their findings, assess evidence quality, quantify primary study overlap and identify evidence gaps.

Searches were conducted across Web of Science, Ovid (PsycINFO, EMBASE), Cochrane and PubMed, supplemented by reference list screening. Study quality was assessed using A MeaSurement Tool to Assess systematic Reviews-2. Study overlap was calculated using the corrected covered area.

We included 20 systematic reviews, synthesising evidence from 179 unique primary studies. Physical barriers to prevent jumping showed strong effect sizes, although primary study overlap was high. Train platform screen doors were associated with reduced site-specific suicide mortality, with no evidence of displacement to other sites, although the number of studies was small. Paracetamol pack size limitation reduced self-poisoning admissions, with mixed impacts on mortality. Bans on highly hazardous pesticides reduced suicide rates. More recent reviews suggest firearms restrictions may reduce suicides, but with small effect sizes and methodological limitations. Evidence quality ranged from high to critically low (12/20 rated as critically low). With the exception of pesticide restrictions, lower and middle-income settings were not represented.

Several means restriction approaches demonstrate effectiveness, although high study overlap and variable study quality were evident. A focus on differential impacts across sociodemographic groups, more evidence from lower and middle-income countries and evidence for suicide prevention on roads and from residential buildings is needed.

CRD42024620103.