Psychometric Properties of the Modified Scale for Suicidal Ideation-Self-Report-Revised With High-Risk Adolescents

In treatment-seeking samples, approximately 40% of adolescents with suicidal ideation transition to engaging in suicidal behavior. Thus, assessment of the severity of suicidal ideation during care is critically important. However, few free, self-report, evidence-based measures that assess for severity of suicidal ideation exist. To address this need, the present study examined several psychometric properties of a revised version of the Modified Scale for Suicidal Ideation-Self Report (MSSI-SR-R) with adolescents. A sample of 284 adolescents (M_age = 15.30; SD = 1.42; range = 12-18; 62.7% White; 75.7% Non-Hispanic/Latinx) enrolled in a partial hospital program (PHP) completed the MSSI-SR-R at the beginning of treatment. The factor structure of the MSSI-SR-R was assessed using bifactor exploratory structural equation modeling. Measurement invariance across sexual identity was also examined. Internal consistency was calculated using omega. Validity was assessed by comparing scores on the MSSI-SR-R to well-validated self-report measures of suicidal thought and behaviors as well as depressive symptoms. Results supported a bifactor model with a general factor and two specific factors (i.e., Desire/Ideation and Plans/Preparation), which was invariant across sexual identity. The MSSI-SR-R total score demonstrated good reliability and was positively associated with measures of suicidal ideation and behaviors as well as depressive symptom severity. Though additional psychometric work is needed, the MSSI-SR-R demonstrated good psychometric properties. It may offer utility in clinical settings as a brief, free, and validated assessment of severity of suicidal ideation.