Date of Defense


Date of Graduation




First Advisor

Scott Gaynor

Second Advisor

Callum Smith

Third Advisor

John Spitsbergen


Depression and anxiety are among the most commonly diagnosed mental health issues in the United States and across the world. Given the increasing prevalence of both diagnoses, the science community has emphasized research in the treatment of disorders, including therapies. Two common treatments used are Cognitive Behavioral Theory (CBT) and Acceptance and Commitment Therapy (ACT). ACT operates on the theory of psychological flexibility as its core construct. CBT uses repetitive negative thoughts and worry as its core constructs. The overall purpose of the study is to determine how well ACT variables compared to CBT variables explain the variation in depression and anxiety. The hypothesis is that a least one ACT process variable will be statistically significant above all competing CBT process variables for predicting psychological distress. Participants in the study were undergraduate or graduate students at Western Michigan University who were at least 18 years of age. The study used a cross-sectional design with process and outcome variables. The ACT process variables were represented by scores on the AAQ-II, Psy-Flex, CFQ, VQ-Obstruction, and VQ-Progression. The CBT process variables were represented by scores on the PSWQ-16 and PTQ. The outcome variable was represented by the DASS-21 Total. Students were asked to take a survey that included these questionnaires via a web-based survey application. Data analysis included a bivariate correlation model and multiple hierarchical multiple regression models. The results of the bivariate correlations demonstrated that every correlation between the outcome and process variables was significant to either the 0.05 or 0.01 parameter. In a multiple linear regression using ACT process variables, the r-squared was 0.454. The same regression using CBT process variables had an r-squared of 0.346. The results of the study demonstrated that while every predictor variable was statistically significant, the ACT process variables consistently had higher predictive utility for the DASS-21 Total compared to the CBT variables.

Access Setting

Honors Thesis-Open Access

PowerPoint.pdf (449 kB)
Defense Presentation

Included in

Psychology Commons