Abstract
Crisis hotlines are direct communication systems, usually telephone-based, set up to prevent suicide. However, few studies have evaluated their effectiveness. The present study aims to perform a systematic review, using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) framework, of the effectiveness of interventions through direct communication systems to reduce the number of suicides or suicide attempts. We searched the MEDLINE, Cochrane, SciELO, and ClinicaTrials.gov databases, and used the 2011 Oxford Centre for Evidence-Based Medicine Levels of Evidence classification. The literature search yielded 267 studies, of which 35 fulfilled the selection criteria. Although significant heterogeneity was found among studies, there is evidence that direct telephone interventions are effective when included in broader preventive protocols and provided by trained staff. Despite the limitations, which included heterogeneity of samples, designs, and outcome measures, we were able to design a protocol for the use of remote services to prevent suicide and suicide attempts. A hotline or similar system could be an effective intervention for broader suicide prevention programs. However, further research is necessary to specify which protocol components are key to enhance effectiveness.