The Brazilian version of the DOS for the detection of orthorexia nervosa: transcultural adaptation and validation among dietitians and Nutrition college students

Abstract

Purpose Orthorexia nervosa has been receiving considerable attention and several tools have been developed to assess it, for instance, the “Düsseldorf Orthorexie Scale” (DOS). Such scale is a validated test to measure orthorexic eating behavior and it has shown good psychometric properties. Therefore, this study aimed to transculturally adapt and validate the Brazilian version of the DOS (DOS-BR). Methods DOS-BR was obtained using the back-translation process after two reviews done by a focus group and after running a pilot-test (n = 64). A self-report questionnaire was administered to a sample of Brazilian dietitians and Nutrition college students (n = 486). To examine the factor structure of the DOS-BR, exploratory factor analysis and confirmatory factor analysis were conducted. The ordinal alpha was examined. Test–retest reliability was evaluated in a sub-sample (n = 159). Convergent validity was assessed by conducting correlation analyses between the DOS-BR and other theoretically related tools (EAT-26 and OCI-R) within the sub-sample. Results A three-factor structure was revealed for the DOS-BR properly fitted (KMO = 0.787). The test showed good internal consistency with an ordinal alpha of 0.795, and it also had excellent test–retest reliability of 0.776. DOS-BR median score was 17 (14–22) in Measurement 1 and 19 (17–22) in Measurement 2. The total score had a positive and moderate correlation with eating disorders symptoms (0.488) and a positive and weak correlation with obsessive–compulsive symptoms (0.224). Conclusion The DOS-BR was culturally and psychometrically adequate for the samples of Brazilian Nutrition-related subjects. The tool is indicated as a reliable alternative to evaluate orthorexia nervosa in Brazilian scenery. Level of evidence Descriptive (cross-sectional) study, Level V.