Construct validation of the portuguese version of the restraint scale

Abstract

The main purpose of this study was to adapt the Restraint Scale (RS) to Portuguese and examine its psychometric properties, specifically its construct validity. Method: In this study, 238 normal-weight adults (82% women; Mean age = 36.6, SD = 15.0) participated in an online survey containing measures of Restraint Scale, Three Factor Eating Questionnaire, Dutch Eating Behaviour Questionnaire, and Body Dissatisfaction and Drive for Thinness scales. Results: Exploratory factor analyses corroborated the two-factors structure found in previous studies, in particular when three items without clear factorial assignment and low correlation were excluded. A final two-factors version of the RS containing seven items presented a very good fit to the measurement model and good internal consistency. Confirmatory factor analysis of the 7-items RS in relation to a three-factor model of overeating, dieting and body dissatisfaction measures revealed that the RS was the only restraint measure loading in all three factors. Conclusion: This suggests that the 7-items Portuguese version of the RS has good psychometric properties and unique features that lend it appropriate to identify and study unsuccessful chronic dieters.