Behavioral functions underlying NSSI and eating disorder behaviors.

Abstract

This study examined whether the psychological functions motivating eating disorder (ED) and nonsuicidal self-injury (NSSI) behaviors are similar, thereby representing shared mechanisms accounting for their high co-occurrence. Self-report data assessing NSSI, ED symptoms, and behavioral functions were collected from 676 adults with recent NSSI (past 6 months; n = 333) or disordered eating ( n = 343). Measurement invariance analyses revealed the same function-factor structure for ED and NSSI behaviors for 8 out of 13 scales. Comparisons of scalar latent means showed that some functions, while relevant to both behaviors, were rated as subjectively more salient to engaging in either ED or NSSI behavior. Similar functions have relevance to understanding engagement in NSSI and ED, but important differences exist in the subjective salience of each function. Treatments focusing on the shared functions of NSSI and ED may have greater success in simultaneously decreasing engagement in these behaviors.