Psychometric properties and construct validity of the Weight-Related Eating Questionnaire in a diverse population.

This study evaluates the 16-item, four-factor Weight-Related Eating Questionnaire (WREQ), which assesses theory-based aspects of eating behavior, across diverse, nonclinical subgroups. A total of 621 men and women aged 18-81 years (34.3 ± 16.4) with a mean BMI of 25.7 ± 6.1 kg/m(2) (range 15.5-74.1 kg/m(2)) were recruited from general education classes at the University of Hawai'i, Manoa and an online survey panel of Hawai'i residents to complete a web-based survey. Participants were predominantly white (23%), Asian/Asian-mix (42%), or Native Hawaiian/Pacific Islander (18%). The WREQ's factor structure was successfully replicated by confirmatory factor analysis (CFA) for the entire sample and by weight status, gender, age, and race with strong internal consistency. Four-week test-retest reliability (n = 31) for the subscales was excellent with interclass correlations of 0.849-0.932. Tests of population invariance confirmed the generalizability of the WREQ across all subgroups having provided no evidence that the factor structure, factor loadings, or indicator intercepts varied significantly between the groups. Multivariate regression analyses showed that emotional eating was independently associated with BMI (β = 0.272, P < 0.001) as well as moderate- and long-term weight change rates (weight gain) in young adults (β = 0.152, P = 0.042) and adults (β = 0.217, P = 0.001). Compensatory restraint was negatively associated with weight gain in adults (β = -0.133, P = 0.039). Routine restraint and emotional eating were highest among dieters. All associations remained significant after accounting for gender, age, and race. The hypothesized WREQ measurement model demonstrated very good construct validity, confirming the unbiased generalizability of the WREQ measure across sex, age, race, and BMI subgroups, and excellent criterion-related validity with respect to current BMI, weight change, and weight control status.