Predicting Suicide and Suicide Attempts in Adults in Acute Hospitals: a Systematic Review of Diagnostic Accuracy Evaluating Risk Scales

Abstract

Aim: To evaluate the diagnostic accuracy of suicide risk scales within hospitals and consider the best scale in predicting suicide and suicide attempt in adults. Background: Many scales are used in routine suicide screening within hospitals to predict suicide and suicide attempts. Currently, there are no systematic reviews which determine if the same scale should be used in inpatient, emergency department and combined settings. Methods: Databases searched include PubMed, Embase, ProQuest, MEDLINE, Web of Science, CINAHL, Cochrane, PsycINFO and Scopus. Grey literature databases - ProQuest Dissertations and Theses, Google Scholar and OpenSIGLE - and reference lists of all included studies were searched. Eligibility criteria included prospective cohort studies in adults with the outcome of suicide or attempted suicides. Methodological quality was assessed using QUADAS-2 and data was extracted using JBI data extraction instrument for diagnostic accuracy studies by two independent reviewers. True positives, true negatives, false positives and false negatives were calculated for sensitivity, specificity, likelihood ratios, predictive values and diagnostic ORs. Results: Thirty-three studies included in the final analysis differed widely based on methodological characteristics and scales used. Sensitivity of scales ranged from 17% to 100%, specificity ranged from 11% to 93%, positive predictive value ranged from 0.43% to 40.9%, and diagnostic OR ranged from 0.77 to 18.5. Significance of study: This systematic review contributes to existing literature by evaluating diagnostic accuracy statistics of scales to guide clinicians into choosing the best. The Manchester Self-Harm Rule and Suicide Crisis Syndrome are the best options for use in the emergency department and inpatient settings respectively, while the Suicide Intent Scale could be used if only one scale is allowed. Future research could be built on this systematic review by measuring pooled sensitivity and specificity and evaluating the different scales used in local hospitals.