Defining negative symptoms remission in schizophrenia using the Brief Negative Symptom Scale.

Abstract:

INTRODUCTION: This study aimed to propose criteria for negative symptoms remission (NSR) in schizophrenia using the Brief Negative Symptom Scale (BNSS). MATERIAL AND METHODS: 274 participants were assessed on the Positive and Negative Syndrome Scale (PANSS), BNSS and Social and Occupational Functioning Assessment Scale (SOFAS). Two criteria for NSR on the BNSS were proposed - NSR based on the BNSS domains scores (NSRBNSS_DOMAINS) and NSR based on 5 key items of the BNSS (NSRBNSS_5ITEMS). A SOFAS score of 61 and above was considered as functional remission (FR). Logistic regressions were run to examine the association between FR and NSR. Receiver operating characteristic (ROC) curve analysis was performed for the NSR criteria on FR. Kappa agreement statistic was used to evaluate the agreement between the two NSR criteria. RESULTS: Eighty-nine (32.5%) participants fulfilled NSRBNSS_DOMAINS criterion whereas 70 (25.6%) participants fulfilled NSRBNSS_5ITEMS criterion. The two NSR criteria had substantial agreement (Kappa statistic=0.797) with each other. Sixty-one (25.3%) participants were in FR. FR was significantly associated with NSR, irrespective of the criterion used. To predict FR, the Area Under the Curve for NSRBNSS_DOMAINS and NSRBNSS_5ITEMS were 0.761 (CI: 0.696-0.826, p