Date of Award


Document Type

Open Access Thesis

Degree Name

Doctor of Psychology (PsyD)



First Advisor

James Theisen, PhD, LP

Second Advisor

Marcia Bennett, PhD, LP

Third Advisor

Abby Hughes-Scalise, PhD, LP


Posttraumatic growth (PTG) has gained considerable research and clinical attention for the past three decades. While the impact of PTG has been well-researched in relation to trauma exposure, medical ailments, or mood related conditions, there are still a number of mental health conditions requiring further analysis. The current study examined the relationship between PTG and key substance use significance indicators, including diagnostic severity of the use disorder and number of previous substance use treatment attempts, among a sample (N = 136) of adult men who were enrolled in a mental illness/chemical dependency (MICD) intensive outpatient program (IOP). This study also examined how posttraumatic stress disorder (PTSD) symptoms may serve as a moderator of the relationship between PTG and substance use indicators. Results showed that PTG was significantly negatively correlated with both substance use severity and the number of previous substance use treatments. PTSD symptom severity was found to moderate the relationship between PTG and substance use severity for both moderate and high levels of PTSD symptoms, but not for participants with low PTSD symptoms. Specifically, those with high PTSD symptoms showed a significantly more negative relationship between PTG and substance use severity as compared to moderate PTSD symptoms. This same moderation effect of PTSD was not found between the number of previous treatments and PTG. Findings suggest that substance use and trauma exposure appear to correlate with the level of resilience in homeless populations. Findings provide a number of important clinical implications around the importance of addressing substance use concerns with populations who experienced trauma, and the role of mental health care in shelter settings. Future directions based on the present study emphasize the continued need for the inclusion of both positive and negative PTG ratings.


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