The reliability and validity of the dichotomous thinking in eating disorders scale.

The Dichotomous Thinking in Eating Disorders Scale (DTEDS) is a short, self-report measure that can be used to assess the presence of a rigid, "black-and-white" cognitive thinking style. It was originally developed for use in a study of psychological predictors of weight regain in obesity. The DTEDS consists of two subscales. Items on the Eating subscale assess dichotomous thinking with regards to eating, dieting or weight, and items on the General subscale assess dichotomous thinking more generally. This study aimed to examine the factor structure and psychometric properties of the DTEDS in a sample of treatment-seeking eating disordered (N=87) and overweight/obese (N=111) women. Confirmatory factor analysis demonstrated that a two-factor model provided a better fit to the data than a one-factor model. The psychometric properties of the final scale were excellent, with evidence being provided for the reliability and validity of the two subscales. Overall, the results indicated that the DTEDS is a reliable instrument that can be used to assess eating-specific as well as more general aspects of dichotomous thinking.