Development and verification of validity and reliability of a short screening instrument to identify psychiatric morbidity

Background and Purpose: The accurate identification of minor mental disorders associated with depression and anxiety in non-psychiatric medical settings is an important component of mental health care. The present study aimed to develop a reliable and valid short screening tool to improve the identification of psychiatric morbidity. Methods: Data from the 50-item Brief Symptom Rating Scale (BSRS-50) obtained from 721 medical inpatients were used to develop a short screening tool (BSRS-5) ot identify psychiatric morbidity. The BSRS-5 comprises 5 symptom items, selected from the BSRS-50, each of which has the highest correlation with the corresponding subscale score of Anxiety, Depression, Hostility, Interpersonal Sensitivity and Additional Symptoms in the BSRS-50. Various types of reliability and validity of the BSRS-5 were assessed in different populations, including 253 human immunodeficiency virus-1 infected outpatients, 257 psychiatric outpatients, 56 psychiatric inpatients, 100 rehabilitation outpatients with chronic low back pain, 2915 university freshmen, and 1090 community members. Results: Internal consistency (Cronbach alpha) coefficients of the BSRS-5 ranged from 0.77 to 0.90. The test-retest reliability coefficient was 0.82. Concurrent validity coefficients between the sum score of BSRS-5 and the General Severity Index of BSRS-50 ranged from 0.87 to 0.95. Choosing 6+ as the cut-off score for psychiatric cases, the rate of accurate classification of BSRS-5 was 76.3% (78.9% sensitivity, 74.3 % specificity, 69.9% positive predictive value, 82.3% negative predictive value). The BSRS-5 could differentiate the severity of illness in psychiatric outpatients based on psychiatrist's ratings using the Clinical Global Impression scale, severity of psychopathology of psychiatric inpatients between admission and discharge, levels of pain indicated by 4 dimensions of the Dallas Pain Questionnaire for outpatients with chronic low back pain, and the severity of psychopathology between university students and community members with and without suicidal ideation. Conclusion: The BSRS-5 can be used to identify psychiatric morbidity in both medical practice and the community.