학술논문

Cross-cultural adaptation of the Beliefs about Medicines Questionnaire into Portuguese
Document Type
article
Source
Sao Paulo Medical Journal. January 2013 131(2)
Subject
Psychometrics
Questionnaires
Medication adherence
Reproducibility of results
Portugal
Language
English
ISSN
1516-3180
Abstract
CONTEXT AND OBJECTIVES The Beliefs about Medicines Questionnaire (BMQ-Specific) has proven useful for measuring patients' beliefs and associating them with non-adherence to treatment in several illness groups. The aim was to cross-culturally adapt the BMQ-Specific into Portuguese for the general population of medicine users. DESIGN AND SETTING Cross-sectional study conducted among users of public hospitals and outpatient clinics in Guarda and Covilhã, Portugal. METHODS The BMQ-Specific was translated using international recommendations for performing cross-cultural adaptation and was administered to 300 patients. An initial principal component analysis (PCA) was conducted with the extraction criterion of eigenvalue > 1.0, followed by a second PCA with restriction to two components. Reliability was assessed by calculating Cronbach's alpha coefficient. RESULTS The mean scores obtained for the Necessity and Concerns subscales of the Portuguese BMQ-Specific were 19.9 (standard deviation, SD = 2.8) (range 10 to 25) and 17.7 (SD = 3.9) (range 6 to 30), respectively. The first PCA produced an unstable three-component structure for the Portuguese BMQ-Specific. The final PCA solution yielded a two-component structure identical to the original English version (a five-item Necessity and a six-item Concerns subscale), and explained 44% of the variance. Cronbach's alpha for the complete Portuguese BMQ-Specific was 0.70, and 0.76 and 0.67 for the Necessity and Concerns subscales, respectively. CONCLUSION A cross-culturally adapted Portuguese version of the BMQ-Specific questionnaire for use among the general population of medicine users was obtained, presenting good internal consistency and component structure identical to the original English version.