Psychology ETDs

Publication Date

Fall 9-6-2021


Background: Few studies have examined a reciprocal parallel process longitudinal trajectory of adolescent substance use and mental health problems simultaneously, and none have described this parallel process for adolescents receiving outpatient substance use treatment. No studies have examined how social support may account for deviations outside the overall trajectories for substance use or mental health problems. Method: Secondary data analysis examined a longitudinal parallel process latent growth model between mental health and substance use problems among adolescents who received outpatient substance use treatment. Results: Findings suggest that mental health and substance use problems are associated both initially and longitudinally, and the effects are reciprocal in nature. Covariates differentially influence the associations between these parallel processes. The reciprocal parallel process was strongest in the combined co-morbid group compared to the other co-morbid groups. Social support significantly predicted mental health problem deviations from the overall trajectory at intake and the 6-month follow-up timepoint. Discussion: This study appears to be the first to identify a reciprocal parallel process relationship between mental health and substance use disorders within a diverse adolescent substance use treatment sample. The combined co-morbid group demonstrated the strongest parallel process relationship. Social support played a minimal role in predicting deviations from the overall trajectory for mental health problems. This study highlights the importance of not assuming that treatment of one disorder should be prioritized over the other, as well as the need for an integrated approach to intervention that begins with adequate screening and assessment of co-occurring problems.

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First Committee Member (Chair)

Jane Ellen Smith, PhD

Second Committee Member

Sarah Erickson, PhD

Third Committee Member

Davood Tofighi, PhD

Fourth Committee Member

Teresa Lafromboise, PhD



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Per instructions from Mayra Estrada on 9/14/21, I have made minor revisions and I am uploading a revised version of the manuscript with the corrected changes to the title and abstract page.