Abstract
BACKGROUND: Among people receiving residential treatment for a substance use disorder (SUD), premature treatment termination predicts poor post-treatment outcomes. We examined the utility of the alternative model for personality disorders (AMPD) for predicting premature residential SUD treatment termination, including interactions with age and gender. METHODS: Participants (N = 374) were receiving residential treatment for SUD and enrolled in a clinical trial with two conditions: Skills for Improving Distress Intolerance (SIDI) and Supportive Counseling (NCT01741415). Participants were assessed at intake on AMPD traits using the Personality Inventory for DSM-5 (PID-5) and tracked longitudinally. After establishing gender and age measurement invariance, we used competing risk models to predict treatment completion versus premature termination using interactions of PID-5 scores with age and gender. FINDINGS: Disinhibition and Negative Emotionality domains and facets predicted premature treatment termination, particularly among younger, male participants. There were positive effects of SIDI on treatment completion for participants with high levels of domain and facet Negative Emotionality. A small proportion (≈ 12 %) of the PID-5 items showed differential item functioning by age or gender; however, the aggregate impact on test-level total scores was negligible. CONCLUSIONS: Participants (particularly young men) displaying poor self-control and emotional regulation are at risk for premature termination. These findings, together with minimal aggregate differential item functioning at the scale level, suggest that the PID-5 is a practically useful, construct-valid, non-proprietary measure, aspects of which can be used for screening in residential SUD treatment. Furthermore, among those with high negative emotionality, SIDI may be effective in preventing premature treatment termination.