The Columbia-Suicide Severity Rating Scale: initial validity and internal consistency findings from three multisite studies with adolescents and adults

Abstract

Objective: Research on suicide prevention and interventions requires a standard method for assessing both suicidal ideation and behavior to identify those at risk and to track treatment response. The Columbia-Suicide Severity Rating Scale (C-SSRS) was designed to quantify the severity of suicidal ideation and behavior. The authors examined the psychometric properties of the scale.

Method: The C-SSRS's validity relative to other measures of suicidal ideation and behavior and the internal consistency of its intensity of ideation subscale were analyzed in three multisite studies: a treatment study of adolescent suicide attempters (N=124); a medication efficacy trial with depressed adolescents (N=312); and a study of adults presenting to an emergency department for psychiatric reasons (N=237).

Results: The C-SSRS demonstrated good convergent and divergent validity with other multi-informant suicidal ideation and behavior scales and had high sensitivity and specificity for suicidal behavior classifications compared with another behavior scale and an independent suicide evaluation board. Both the ideation and behavior subscales were sensitive to change over time. The intensity of ideation subscale demonstrated moderate to strong internal consistency. In the adolescent suicide attempters study, worst-point lifetime suicidal ideation on the C-SSRS predicted suicide attempts during the study, whereas the Scale for Suicide Ideation did not. Participants with the two highest levels of ideation severity (intent or intent with plan) at baseline had higher odds for attempting suicide during the study.

Conclusions: These findings suggest that the C-SSRS is suitable for assessment of suicidal ideation and behavior in clinical and research settings.

FIGURE 1. Baseline Rates of Suicidal Ideation and Lifetime Actual Attempts in Three Studies^a

^a Study 1 was a treatment study of adolescent suicide attempters (N=124); study 2 was a medication efficacy trial in depressed adolescents (N=312); study 3 was a study of adults presenting to an emergency department for psychiatric reasons (N=237). In study 1, ideation data for “last week” were missing for 17 (13%) subjects. In study 2, ideation data at baseline were missing for 97 (31%) subjects. ^b In study 1, among patients with lifetime actual attempts, 46.8% had multiple actual attempts.

FIGURE 2. Number of Cases in Study 1 Identified on the Columbia–Suicide Severity Rating Scale (C-SSRS) Behavior Subscale and the Columbia Suicide History Form, by Type of Behavior^a

^a Total N included all those assessed with both the C-SSRS (past week and since last assessment combined) and the Columbia Suicide History Form. kappa=0.66, 95% CI=0.23–1.00.

FIGURE 3

Mean Values in Study 1 for the Severity and Intensity of Ideation Subscales of the Columbia–Suicide Severity Rating Scale (C-SSRS) and the Scale for Suicide Ideation (SSI) Total Score, by Treatment Week

FIGURE 4

Proportion of Cases in Study 1 Identified on Columbia–Suicide Severity Rating Scale Behavior Item and by the Suicide Evaluation Board