Evaluating Concordance Between the Suicide Crisis Syndrome Checklist (SCS-C) and Revised Suicide Crisis Inventory (SCI-2)

Background: The suicide crisis syndrome (SCS) is a proposed diagnostic construct under consideration for inclusion in DSM as a suicide-specific syndrome. The SCS is an acute affective-cognitive state, characterized by entrapment (Criterion A), affective disturbances (Criterion B1), loss of cognitive control (B2), hyperarousal (B3), and social withdrawal (B4). Suicidal ideation is not a criterion. While psychometrically valid self-report measures of SCS are well-established, the need for a psychometrically valid interview remains. A clinician-administered tool is essential for broader clinical use and dissemination. Aims: This study assesses the convergent validity of the Suicide Crisis Syndrome Checklist (SCS-C), a semistructured interview, relative to the Revised Suicide Crisis Inventory (SCI-2), a validated dimensional self-report measure. The goals of this study are: (1) to evaluate the convergent validity of the Suicide Crisis Syndrome Checklist (SCS-C) against SCI-2 and (2) to evaluate classification configurations of SCS-C criteria based on sensitivity and specificity. Method: In a sample of 217 adult psychiatric inpatients, receiver operating characteristic curve (ROC) analyses investigated each individual SCS-C criterion and configurations of criteria (e.g., inclusion of one, two, three, or all four B criteria) for concordance with SCI-2. Sensitivity and specificity values corresponded to the score with the highest Youden’s J. Results: The first four SCS-C criteria showed good concordance with corresponding subscale scores (AUC = .794 – .866) while the final criterion, B4 Social Withdrawal, showed weaker alignment (AUC = .716). A configuration of Criterion A plus three B Criteria demonstrated particularly strong concordance (AUC = .800, sensitivity = .861, specificity = .654). Limitations: Recruiting from an acute inpatient setting and administering via research assistants, potentially affecting generalizability, and not conducting further construct validity tests. Conclusions: Findings support the convergent validity of the SCS-C and suggest at present the SCS-C corresponds most closely with the SCI-2 when utilizing four of the five criteria.