The Effect of Sorority Membership on Eating Disorders, Body Weight, and Disordered-Eating Behaviors.

Eating disorders are currently the deadliest mental disorder in the United States, affecting an estimated 12%-25% of all college women. Previous research has found a positive correlation between sorority membership and eating disorders, but the causal link has not been firmly established. We contribute to the literature by investigating a possible causal link among sororities and diagnosed eating disorders, measurable weight outcomes, and disordered-eating behaviors using data from the American College Health Association Survey. We handle the potential endogeneity of sorority membership using propensity score matching and instrumental variable methods to determine whether joining a sorority is a cause of the weight-related outcomes we study. We find that sorority members exhibit worse weight-related outcomes than those not in a sorority. However, our propensity score matching and instrumental variable results suggest that, other than BMI, this is merely a correlation, and there is little evidence that sorority membership is a cause of the outcomes we study.