Date of Award


Degree Name

Doctor of Philosophy



First Advisor

Drake, Chad


The science of psychotherapy is reliant on various research designs to provide evidence for and bolster the efficacy of therapeutic interventions, techniques, and packages. Among the therapeutic orientations with ample evidence of support is Acceptance and Commitment Therapy (ACT; Hayes et al., 1999). The creators of ACT propose targeting psychological flexibility, broadly defined as engaging with personal values with no regard of the presence of unwanted and undesired experiences. The Life Skills Modules protocol was developed to provide graduate student trainees with a simple and accessible tool to provide effective ACT treatment clients from the local community seeking treatment at the Southern Illinois University Clinical Center. The results of the study indicates that the clients improved in psychological flexibility, inflexibility, and symptoms of anxiety and depression, though this improvement is not explained by number of sessions nor completion of the protocol. Additionally, improvement in flexibility and inflexibility accounted for a significant portion of the variance in the improvement in symptoms as well. Flourishing did not improve within the clients. This study, while being marred with significant limitations, supports the ACT model of change of targeting psychological flexibility and inflexibility as being important towards improvement in treatment. The results of the study do not indicate the use of the protocol is the explicit cause of improvement. Discussion of the results and limitations are provided.




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