Development and Initial Validation of a Brief Symptom Measure

UNLABELLED: Self-report measures of psychiatric symptomatology are important components of treatment monitoring and service evaluation programs. However, the currently available measures have numerous limitations including being symptom or disorder specific, suited to a limited range of clinical settings, and having excessive burden. Consequently, there is a need for a brief and psychometrically robust measure of global symptomatology that is applicable across diverse clinical settings, therapeutic modalities and patient populations. This paper presents the development and initial validation of such a scale, the Brief Symptom Measure-25 (BSM-25). We report findings from multiple samples examining the reliability, validity, sensitivity to change and factor structure of the new instrument. The results suggest that the BSM-25 has good reliability, is suitable to multiple levels of care, sensitive to treatment induced change and has promising validity. Exploratory bifactor modelling revealed that all items loaded strongly on a general factor (bifactor) while also forming two minor group factors. Potential limitations of this study along with future research and clinical applications of the BSM-25 are discussed. KEY PRACTITIONER MESSAGE: The BSM-25 is a broad measure of symptom severity that is easy to administer and score, appropriate for divers patient populations, and suitable for monitoring progress in routine clinical practice.