Weight Bias Internalization Scale discriminates obese and overweight patients with different severity levels of depression: the Italian version of the WBIS

We have investigated the psychometric properties of the Italian version of the weight bias internalization scale (WBIS) in overweight and obese patients who were attending weight loss programs. Participants were 386 overweight and obese patients admitted in two medical centers specializing in the treatment of obesity. All the patients were administered the WBIS, and measures of binge eating, depression, self-esteem, and body dissatisfaction. Confirmatory factor analysis failed to confirm the fit of the original 11-item unidimensional model. Item analysis and exploratory factor analysis indicated that 9 items included in the original measure (the items 1 and 9 were excluded because low item-total correlations) formed a reliable unidimensional measure of internalized weight bias (WBIS-9). The WBIS-9 was significantly correlated with convergent measures and was able to categorize individuals with different severity levels of depression (sensitivity of 0.72 and specificity of 0.70). The WBIS-9 may be useful in clinical practice to discriminate patients with more severe psychopathology, comorbid disordered eating patterns, and risk for poor outcomes.