Development and validation of the eating pathology symptoms inventory (EPSI)

Many current measures of eating disorder (ED) symptoms have 1 or more serious limitations, such as inconsistent factor structures or poor discriminant validity. The goal of this study was to overcome these limitations through the development of a comprehensive multidimensional measure of eating pathology. An initial pool of 160 items was developed to assess 20 dimensions of eating pathology. The initial item pool was administered to a student sample (N = 433) and community sample (N = 407) to determine the preliminary structure of the measure using exploratory and confirmatory factor analyses. The revised measure was administered to independent samples of patients recruited from specialty ED treatment centers (N = 158), outpatient psychiatric clinics (N = 303), and students (N = 227). Analyses revealed an 8-factor structure characterized by Body Dissatisfaction, Binge Eating, Cognitive Restraint, Excessive Exercise, Restricting, Purging, Muscle Building, and Negative Attitudes Toward Obesity. Scale scores showed excellent convergent and discriminant validity; other analyses demonstrated that the majority of scales were invariant across sex and weight categories. Eating Pathology Symptoms Inventory scale scores had excellent internal consistency (median coefficient alphas ranged from.84 -.89) and reliability over a 2- to 4-week period (mean retest r =.73). The current study represents one of the most comprehensive scale development projects ever conducted in the field of EDs and will enhance future basic and treatment research focused on EDs.