Assessment of Dietary Restraint: Psychometric Properties of the Revised Restraint Scale in Hong Kong Adolescents

BACKGROUND The psychometric properties of the Revised Restraint Scale (RRS) have been well established in western populations but not in Chinese adolescents. PURPOSE This study investigated the psychometric properties of RRS and its validity in different subgroups for Hong Kong Chinese adolescents. METHOD In 2007, 909 Hong Kong students aged 12 to 18 years (55.3% boys) completed a questionnaire including demographic items, RRS, Eating Attitudes Test (EAT-26), and Motivation for Eating Scale (MFES)-physical. Moreover, subjects' height and weight were measured. To examine the factor structure of RRS, the whole sample was randomly split into two groups (sample 1: N=454 and sample 2: N=455) for exploratory factor analysis (EFA) and confirmatory factor analysis (CFA), respectively. Convergent and discriminant validity of RRS were investigated by correlating the RRS with EAT-26 and MFES-physical. Multigroup CFA was conducted to test the three-factor model of RRS in different sex, age, and weight status subgroups. RESULTS Results of EFA for sample 1 revealed three strongly correlated factors for the RRS construct, and were supported by the CFA results in sample 2. Multigroup CFA further suggested that the three-factor model of RRS was stable across sex, age, and weight status subgroups. CONCLUSIONS A new three-factor model is proposed for Hong Kong adolescents in this study. In general, RRS is a reliable and valid measure of restrained eating for adolescents, regardless of sex, age, and weight status.