To be diagnosed with OSFED, an individual meets some, but not all of the criteria for a subtype of an eating disorder. People with Atypical Anorexia Nervosa, fit all the criteria for Anorexia Nervosa but are within a normal weight range. People who fit all the criteria for binge eating disorder or bulimia nervosa but the symptoms of their disorder are not frequent enough to fit the criteria may be diagnosed with OSFED instead.
A person who purges without binge eating does not meet the criteria for the other subcategories of eating disorders and will often be diagnosed with Purging Disorder OSFED type. Night Eating Syndrome is another Other Specified Feeding and Eating Disorder that occurs in individuals who repeatedly eat after waking up from sleep or eat large amounts of food after dinner.