Guidelines for Rigorous and Reproducible Research on Other Specified Feeding or Eating Disorder: Commentary on Dang et al. (2024).

Dang et al.'s review concludes that atypical anorexia nervosa (atypical AN), purging disorder (PD), and night eating syndrome (NES) are clinically significant and severe eating disorders (EDs). However, findings are unlikely to alter their status in future editions of the DSM due to limitations in the literature to date. Guidelines are offered to promote rigorous and reproducible research on other specified feeding or eating disorder OSFED. First, published research diagnostic criteria for atypical AN, PD, and NES should be consistently used to ensure findings across studies reflect the same conditions. Second, operational definitions are recommended for "recurrent" as at least twice within a 3-month period, minimum duration as at least 1 month, and "significant weight loss" as >5% BMI reduction within 1 month. Third, Thomas's and Gydus's trumping scheme for differential diagnosis of OSFED subcategories is endorsed but should prioritize identifying treatment targets based on medical morbidity over mirroring existing diagnostic algorithms. Fourth, a systematic approach for establishing clinical significance is recommended that explicitly notes medical risk associated with malnutrition, purging and nonpurging behaviors, and relevance of marked distress related to binge eating and body image disturbance. Adoption of these guidelines will facilitate necessary research on clinical utility.