Reliability and validity of the brief psychosomatic symptom scale (BPSS) in patients from general hospitals

To verify the Brief Psychosomatic Symptom Scale (BPSS) among patients with psychosomatic-related disorders in general hospitals and determine the threshold of BPSS. The BPSS is a shortened 10-item version of the psychosomatic symptoms scale (PSSS). Data from 483 patients and 388 healthy controls were included for psychometric analyses. Internal consistency, construct validity, and factorial validity were verified. The threshold of BPSS in distinguishing psychosomatic patients from healthy controls were determined using receiver operating characteristic (ROC) curve analysis. The ROC curve of the BPSS was compared with that of the PSSS and patient health questionnaire-15 (PHQ-15) by using Venkatraman's method with 2000 times Monte-Carlo simulations. The reliability of the BPSS was good with Cronbach's α of 0.831. BPSS was significantly correlated with PSSS (r = 0.886, P < 0.001), PHQ-15 (r = 0.752, P < 0.001), PHQ-9 (r = 0.757, P < 0.001) and GAD-7 (r = 0.715, P < 0.001), which indicated good construct validity. ROC analyses demonstrated that the AUC of the BPSS was comparable with that of PSSS. The gender-specific threshold of BPSS was determined as ≥8 in males and ≥ 9 in females. The BPSS is a brief and validated instrument for screening common psychosomatic symptoms.