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Date of Award

Fall 11-11-2018

Degree Type

Dissertation (On-Campus Access Only)

Degree Name

Doctor of Psychology (PsyD)

Committee Chair

Paul G. Michael, PhD


Attention-Deficit/Hyperactivity Disorder (ADHD) is commonly identified as a neurodevelopmental disorder occurring in children with symptoms attenuating as they mature into adulthood. However, impairing symptoms persist into adulthood for substantial portion of them. The research on psychological treatments for adult ADHD is not as robust as it is for children. Prior to the conception of this study, one prior meta-analysis of 12 psychotherapy studies had been published, in 2011. In order to provide further insight regarding effective psychological treatment for adults with ADHD, the current study is an up-to-date meta-analytic review of 26 studies with N participants, examining psychotherapeutic interventions for adults with ADHD. Between-group effect sizes for treatment vs. no treatment, waitlist controlled treatment, or treatment as usual were large (d = 1.02, 95% CI = 0.69 - 1.35) across eight study-level effect sizes. Between-group comparisons for different treatment protocols was not possible due to scarcity of study-level effect-size data. Within-group effect sizes using pre- and post-treatment data were medium to large (d = 0.82, 95% CI = 0.68 - 1.01). All effect sizes used either self- or clinician-reported ADHD symptoms. Insufficient data were available to thoroughly conduct analyses of peripheral difficulties related to ADHD (i.e. functional abilities, organizational skills, or productivity). Effects related to treatment orientation produced meaningful distributions for Manualized CBT, Cognitive Remediation, Manualized DBT, and Mindfulness, and Clinical Management; however, there was no evidence to suggest significant differences between the various manualized treatments developed for adult ADHD. Total number of sessions, length of sessions, or length of treatment did not explain variability in treatment outcomes. Participant characteristics such as age gender, or ethnicity did not significantly moderate outcomes. Implications for future research and clinical practice are discussed.