The transition from DSM-IV to DSM-5 relaxed diagnostic criteria for anorexia nervosa and bulimia nervosa, and recognised a third eating disorder, binge eating disorder. However, a large proportion of cases remain in the ill-defined category of 'other specified feeding and eating disorders'. We sought to investigate the utility of a proposed solution to classify this group further, subdividing based on the dominant clinical feature: binge eating/purging or restraint. Cluster analysis failed to identify clusters in a treatment-seeking sample based on symptoms of restraint, binge eating, purging and over-evaluation of shape and weight. Further investigation of this highly heterogeneous group is required.