Psychometric Properties and Transcultural Adaptation of Turkish Version of the Basel Assessment of Adherence to Immunosuppressive Medication Scale

Abstract

Objectives: This study aimed to translate BAASIS (Basel Assessment of Adherence to Immunosuppressive Medication Scale) into Turkish and to test the psychometric properties of the translated Turkish version of the instrument. Materials and Methods: In this single-center crosssectional study, we included 100 kidney transplant recipients in a university hospital in a western city of Turkiye. The Translation and Cultural Adaptation Report from Professional Society for Health Economics and Outcomes Research was used for the transcultural adaptation of BAASIS to Turkish. We tested the validity of the BAASIS Turkish version by the level of evidence according to the American Educational Research Association guidelines: content validity, internal structure, and relations to other variables. We calculated item-total correlations of the BAASIS Turkish version to examine internal consistency reliability. Results: The content validity index score of BAASIS was calculated as 1.00, indicating agreement between the experts. Exploratory factor analysis evaluated the internal structure of BAASIS, and the coefficients for inter-item correlations ranged from 0.170 to 0.395. The Immunosuppressive Treatment Adherence Scale and the BAASIS nonadherent scores were significantly correlated (r = 0.673, P < .001). The coefficients for item-total correlation analyses ranged from 0.160 to 0.470. Conclusions: The BAASIS Turkish version has acceptable psychometric properties. The scale can be used in clinical practice and research projects in transplantation to assess immunosuppressive medication adherence.