BackgroundThe Suicide Trigger Scale (STS) was designed to measure the construct of an affective ‘suicide trigger state.’ This study aims to extend the inpatient setting validation study of the original Suicide Trigger Scale version 2 to the revised Suicide Trigger Scale version 3 (STS-3) in an acute psychiatric emergency room setting.MethodsThe 42-item STS-3 and a brief psychological test battery were administered to 183 adult psychiatric patients with suicidal ideation or attempt in the psychiatric emergency room, and re-administered to subjects at 1 year follow up. Factor analysis, linear and logistic regressions were used to examine construct structure, divergent and convergent validity, and construct validity, respectively.ResultsThe STS-3 demonstrated strong internal consistency (Cronbach’s alpha 0.94). Factor analysis yielded a three-factor solution, which explained 43.4% of the variance. Principal axis factor analysis was used to identify three reliable subscales: Frantic Hopelessness, Ruminative Flooding, and Near-Psychotic Somatization (Cronbach’s alphas 0.90, 0.80, and 0.76, respectively). Significant positive associations were observed between Frantic Hopelessness and BSI depression and anxiety subscales, between Ruminative Flooding and BSI anxiety and paranoia subscales, and Near Psychotic Somatization and BSI somatization subscales. Suicidal subjects with suicide attempt history had mean scores 7 points higher than those without history of suicide attempts. Frantic hopelessness was a significant predictor of current suicide attempt when only attempts requiring at least some medical attention were considered.ConclusionThe STS-3 measures a distinct clinical entity, provisionally termed the ‘suicide trigger state.’ Scores on the STS-3 or select subscales appear to relate to degree of suicidality in terms of severity of ideation, history of attempt, and presence of substantive current attempts. Further study is required to confirm the factor structure and better understand the nature of these relations.