The food amount rating scale: Development, reliability, and validity

Objective: Implied in measures of binge eating is the assumption that individuals agree on what comprises a large amount of food. However, whether individuals estimate food amounts similarly or whether estimation of food amounts varies as a function of personal characteristics is unknown. The Food Amount Rating Scale (FARS) is a standardized set of stimuli for assessing individuals' judgment of food amounts. Research Methods and Procedures: Two versions of the FARS were developed, and their psychometric properties were assessed. These versions are the same in all respects except that the rater is instructed to rate various food amounts for the average woman on Form W and for the average man on Form M. Results: Content validity was confirmed by 14 researchers and research assistants in the field of eating disorders. The FARS is a 24-item inventory with adequate test-retest reliability (Form W = 0.85; Form M = 0.87) and split-half reliability (Form W = 0.90; Form M = 0.89). Convergent validity is suggested by the finding that ratings for the average woman (Form W) were significantly higher than ratings for the average man (Form M). Discussion: The FARS is a psychometrically sound tool for use in basic research focused on identifying whether the subjective judgment of food amounts varies as a function of personal characteristics and in clinical research where it may be important to know how individuals judge food amounts.