Validation and Polish Adaptation of the Authorized Bratman Orthorexia Self-Test (ABOST): Comparison of Dichotomous and Continuous Likert-Type Response Scales

PURPOSE: Although research on orthorexia nervosa (ON) has developed in recent years, there exists a continuous need to develop valid tools to assess ON risk, according to strict diagnostic criteria. The present study aims to conduct Polish adaptation and validation of the Authorized Bratman Orthorexia Self-Test (ABOST), through a comparison of dichotomous and continuous Likert response scales. PARTICIPANTS AND METHODS: This cross-sectional study involved 472 people with mean age of 27 years (ranging between 18 and 78 years, M = 26.88, SD = 10.40). The survey included demographic questions and measures of orthorexia (the ABOST and ORTO-15), eating disorders (EAT-26), body mass index (BMI), obsessive–compulsive disorder (OCI-R), anxiety (GAD-7), and depression (PHQ-9). The following statistical tests were performed to explore the psychometric properties of the ABOST: descriptive statistics, Student’s t-test, Pearson’s correlation, Cronbach’s α reliability, exploratory factor analysis (EFA), and confirmatory factor analysis (CFA). RESULTS: The ABOST using a five-point Likert scale for responses demonstrated good psychometric properties. The CFA goodness-of-fit indices confirmed the one-factor solution. Positive correlations were found between the ABOST and the ORTO-15, EAT-26, OCI-R, GAD-7, and PHQ-9. Women scored higher in the ABOST than men, while BMI was unrelated to the ABOST. CONCLUSION: The ABOST using the Likert scale provides a reliable and valid instrument to assess ON risk, as indicated by the face, structural, and convergent validity results. However, more research in various countries is needed, in order to verify the results of this study.