Cross-cultural adaptation, reliability, and content validity of the Brief Negative Symptom Scale (BNSS) for use in Brazil

Abstract Background The Brief Negative Symptom Scale (BNSS) assesses the presence and intensity of negative symptoms in schizophrenia. Objectives This study aimed to carry out the BNSS cross-cultural adaptation to the Brazilian Portuguese language and verify its content validity and reliability. Methods This is a methodological study that followed these steps: (1) implementation of the cross-cultural adaptation and translation protocol, (2) BNSS adapted content validation, and (3) reliability assessment. Six experts participated in the adaptation process. The sample consisted of 30 indiv...