Factor structure of the Subjective Well-being under Neuroleptic treatment Scale-short form in schizophrenic outpatients: Five factors or only one?

Abstract

Backround and aim: The Subjective Well-Being under Neuroleptics Scale, short form (SWNS), is a self-report measure that evaluates the states of well-being of schizophrenia patients using antipsychotic drugs independently from psychopathology of disease. This study examined the factor structure of the Turkish version of the scale using high-level statistical analyses. Methods: The SWNS was translated into Turkish and applied to 103 schizophrenic patients. A type of multi-trait-multi-method (MTMM) confirmatory factor analysis was conducted to determine the factor structure of the Turkish version of the scale. Results: The results of factor analysis of the SWNS were incompatible with the factor structure of the original scale. A set of MTMM analyses showed distinct method effects for both positive and negative item wording in the scale. In light of these findings, the factor structure of the SWNS was determined as having a one-dimensional structure, with bias due to item wording. Conclusions: The results of the present investigation indicated that the sub-factors of the SWNS failed to emerge from the data. This study is the first to show that there is an urgent need for further examination of the factor structure of the SWNS with regard to method effects. This issue has important implications for the use of sub-factors by both researchers and practitioners.