Predictive Validity of Purging Disorder: A 10-Year Follow-Up Study Comparing Prevalence and Psychosocial Outcomes for...

Specific diagnostic criteria for purging disorder (PD) are not currently provided in the DSM-5. The current study aims to compare point prevalence estimates and evidence of predictive validity for four alternative criteria sets for PD for men and women.

Survey data collected in college (N = 3291) and at 10-year follow-up (n = 2223) were used in analyses. Point prevalence was assessed at both time points and compared in men versus women as well as in college versus at 10-year follow-up. Predictive validity was assessed using multiple linear regressions to determine prospective associations for each PD definition versus no eating disorder across external validators.

Point prevalence was greater in women than in men in college across all definitions of PD, and no sex differences were found at follow-up. Point prevalence was greater in college than at follow-up in all but the narrowest definition of PD which required purging, on average, twice per week. Predictive validity was supported for PD defined by self-induced vomiting, laxative or diuretic misuse, with evidence of lower satisfaction with work and career at follow-up.

Together, findings support defining PD through self-induced vomiting, laxative use, or diuretic use to influence body shape or weight, on average, at least once per week. Specifying diagnostic criteria for PD that demonstrate evidence of concurrent and predictive validity will contribute to improved diagnostic reliability, screening, assessment, and support future research efforts to improve treatment.