Invariance of the Eating Disorder Inventory-Drive for Thinness Subscale Across University and Community Samples

• Published in: Psychological assessment 2022-04, Vol.34 (4), p.341-352
• Main Authors: Rancourt, Diana, Choquette, Emily M., Ahlich, Erica, Lang, Brittany M., Verzijl, Christina L., Palermo, Madeline, Belzak, William C. M.
• Format: Article
• Language: English
• Subjects: Age Differences; Body Mass Index; College Students; Colleges & universities; Communities; Differential Item Functioning; Eating behavior; Eating Disorders; Female; Human; Human Sex Differences; Impact analysis; Inventories; Male; Measurement; Measurement Invariance; Motivation; Quantitative psychology; Test Validity
• ISSN: 1040-3590; 1939-134X
• DOI: 10.1037/pas0001095

The Eating Disorder Inventory-Drive for Thinness (EDI-DT) subscale is commonly used in research and as an eating disorder screening measure, but extant evidence is scant regarding its psychometric properties. University and community samples often are treated as interchangeable in terms of research conclusions. Given established demographic differences between these two populations, the present study tested measurement invariance of the EDI-DT across these two sample types. Two large samples of university students (n = 537; 50% female, 67% White; n = 584; 52% female, 67% White) and community participants (n = 535; 57% female, 81% White; n = 533; 63% female, 82% White) completed the EDI-DT online. Multiple group confirmatory factor analyses tested configural, metric, scalar, and strict invariance by sample type. The EDI-DT subscale was not invariant across university and community samples. Post-hoc-regularized multiple nonlinear factor analyses suggested potential item bias associated with sample type, age, and body mass index on six of the seven items. Item bias, however, appeared to be associated with minimal clinical impact. Collectively, results suggest that the EDI-DT may be functionally invariant and appropriate for use with broad populations. Public Significance Statement The Eating Disorder Inventory-Drive for Thinness (EDI-DT) subscale is commonly used in research and clinical work. Though how individuals interpret the items on the EDI-DT differs by age and body mass index (BMI), this did not appear to impact clinical conclusions. Researchers and clinicians can use the EDI-DT with populations of diverse age, BMI, and sex.