Examining the structure of eating pathology through scale construction

Eating disorders are alarmingly prevalent and potentially lethal. The proper assessment of eating disorder symptoms is therefore crucial for the early identification and treatment of those suffering from these serious illnesses. Current measures of eating disorder symptoms are either very narrow in scope (e.g., assess only one aspect of disordered eating, such as bingeing) and/or have one or more serious limitations, such as inconsistent factor structures and/or poor discriminant validity. Because several of the existing measures of eating disorders were created over 20 years ago, many of these limitations are the direct result of out-dated scale development methods and testing.The goal this study was to determine the structure underlying the symptoms of eating disorders and develop a multidimensional measure of eating pathology based on this structure. To accomplish this goal, an initial item pool was developed to assess 20 dimensions of eating pathology. The initial item pool of 160 items 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 then administered to independent samples of psychiatric patients (N=190) and students (N=227). Exploratory and confirmatory factor analyses revealed a 7-factor structure that showed excellent convergent and discriminant validity. The final measure was also internally consistent (median coefficient alphas ranged from .84-.89) and reliable over a two- to four-week period (r's ranged from .70-.84). The current study represents one of, perhaps, the most comprehensive scale development project ever conducted in the field of eating disorders and is expected to improve future basic and treatment research focused on eating disorders.