DSM-5 reduces the proportion of EDNOS cases: evidence from community samples.

OBJECTIVE: Eating Disorder Not Otherwise Specified (EDNOS) constitute the most common eating disorder among those seeking treatment at eating disorder facilities; they are even more common among persons with eating disorders the community. This study compares the impact of applying the revised diagnostic criteria proposed by the DSM-5 workgroup, and the broad categories for the diagnosis of eating disorders (BCD-ED) proposed by Walsh and Sysko on the prevalence of EDNOS.
METHOD: In two nationwide epidemiological studies the prevalence of eating disorders among female high school (n = 2,028) and university students (n = 1,020) was examined using DSM-IV criteria. We used a two-stage design, administering a questionnaire in the first stage and an interview in the second stage.
RESULTS: In the combined samples 118 cases of eating disorders (DSM-IV) were detected, of which 86 were diagnosed as EDNOS (72.9%). Application of the DSM-5 criteria reduced the number of EDNOS cases to 60 (50.8%) or to 52 (44%), when using a BMI <18.5 as cutoff for "significantly low weight" criterion in AN; with the use of BCD-ED criteria, only 5 (4.2%) cases of EDNOS remained. DISCUSSION: Proposed criteria set for DSM-5 substantially reduce the number of EDNOS cases. However, the BCD-ED scheme further reduces its proportion, almost eliminating it.