Factor structure and psychometric properties of the TFEQ in morbid obese patients, candidates to bariatric surgery.

BACKGROUND To analyze the factor structure and psychometric properties of the TFEQ in a morbid obese Spanish sample of bariatric surgery candidates. METHOD Multi-trait/ multi-item analyses and alpha coefficients were conducted to test the convergent /discriminant validity and the internal consistency reliability. Principal components analyses (varimax) were used to explore the factor structure. Sub-group factor analyses by gender, age and body mass index (BMI) were conducted to identify unstable items. RESULTS The internal structure of the original TFEQ factors was unsatisfactory, especially the Disinhibition Scale. Most Disinhibition and Hunger items were grouped on one factor labeled “Dysregulation Eating”. Cognitive Restraint was split into two factors. The first one, related to the behavioral component of Restraint, labeled “Restrained Behaviour” and the second one related to weight and eating concerns called “Predisposition to Restraint”. CONCLUSIONS The original factor structure of the TFEQ was not replicated. A revised 23-item instrument, representing the three new derived factors is offered as a valid screening instrument for severely obese patients.