Which Domain of the PSY-5 Is Most Relevant to Substance Use?

Substance use has generally been related to lower levels of agreeableness and conscientiousness, but has evidenced relationships with other personality trait domains as well, including impulsivity. This study was conducted to determine which trait domain of personality is most related to substance use from the perspective of the Personality Psychopathology Five model (Harkness & McNulty, 1994). Archival data were used from 2 clinical settings: 1 outpatient community mental health center and 1 inpatient Veteran's Affairs hospital. The outpatient sample was mostly female (58.9%), White (78.7%), and had a mean age of 33.01 (SD = 10.26). The inpatient sample was entirely male, predominantly White (91.5%), and had a mean age of 48.03 (SD = 13.88). Correlations were conducted to identify the Minnesota Multiphasic Personality Inventory-2-Restructured Form Personality Psychopathology Five scales (Ben-Porath & Tellegen, 2008; Harkness etal., 2013) that were significantly related to variables measuring substance use. Subsequent regression analyses revealed that Disconstraint was the only significant predictor in the majority (89%) of analyses. In the event Disconstraint was not the only significant predictor, it continued to exhibit the largest unique predictive impact in the regression models. These results suggest that Disconstraint is the Personality Psychopathology-Five dimension most relevant to substance use.