Estimating Suicidality as an Outcome Measure in Clinical Trials of Suicide in Schizophrenia

A Suicide Monitoring Board (SMB) evaluated putative events of suicidal behavior to determine whether they should be counted as outcome data (endpoints) in the International Suicide Prevention Trial (InterSePT) study. The InterSePT study compared clozapine and olanzapine prospectively, on reduction of suicidality in schizophrenia and schizoaffective disorder. SMB members, blinded to patient identification, evaluated packages of clinical information and the forms used to summarize the putative events and their context. The SMB members met regularly by international teleconference to discuss ratings they found problematic and to achieve consensus. Exactly 243 of the 980 patients enrolled (24.8%) were considered to have experienced 577 suicidal events. Of these events, 483 (83.7%) were confirmed by the SMB as real or valid endpoints. Before the consensus discussions, acceptable levels of agreement (k = 0.52) were reached among the SMB members regarding ratings considered as valid suicidal events; agreement increased (k = 0.64) when consensus ratings and those of on-site psychiatrists also blinded to treatment were also included. This article discusses our experience of evaluating schizophrenia patients for suicidality in general and in particular from reviewing chart information. The process of making clinical judgments regarding the seriousness of suicidal behavior in schizophrenia patients and their suicidal risk warrants further study.