Measurement invariance of the Intuitive Eating Scale-2 across country, ethnicity, sex, and sexual orientation: A cross-cultural study between Brazil and the U.S.

Intuitive eating is defined as being connected to internal hunger, satiety, and appetitive cues and flexibly using these cues to determine when, what, and how much to eat. The Intuitive Eating Scale-2 (IES-2) is a widely used measure of facets of intuitive eating. However, the scale has shown unstable factor structure in several validation studies and there is a lack of studies investigating the measurement invariance of the IES-2 beyond sex. We aimed to evaluate the psychometric properties of the IES-2, testing several factor structures among Brazilian and U.S. samples of men and women; to test measurement invariance across country of origin, ethnicity, sex, and sexual orientation; and to evaluate its internal consistency. Three models of the latent structure of the IES-2 were tested using confirmatory factor analyses (CFA) in a total of 1072 young adults (452 Brazilians and 620 Americans), aged 18-35 years. Results demonstrated that only a 3-factor solution with 11 items of the IES-2 showed adequate fit to the data for both countries. This model demonstrated scalar invariance across sex and sexual orientation, but only configural invariance was found across country of origin and ethnicity. Good internal consistencies were found for both the Brazilian and American samples. The present study provides support for a 3-factor solution with 11 items of the IES-2, to Brazilian and American samples. The study also offers evidence of internal consistency, and invariance between sex (i.e., male and female) and sexual orientation (i.e., heterosexual participants and sexual minority participants).