Date of Award


Degree Name

Master of Science


Behavior Analysis and Therapy

First Advisor

Dixon, Mark


Psychological flexibility has been identified as an important construct within Relational Frame Theory and the examination of third-wave behavioral therapies. While psychological flexibility is defined within the context of relational responding, there is no research that directly assesses its relationship to measures of equivalence. The current study examined the relationship between PEAK Equivalence Pre-Assessment and scores of psychological inflexibility (via the AFQ-Y) in school-aged children with disabilities. Pearson correlations were utilized to examine the relationships between scores on PEAK and the AFQ-Y, as well as to examine the correlations among PEAK subtests. A large negative and statistically significant correlation (r =-.64, p < .05) was found between measures of psychological inflexibility and PEAK equivalence scores. Correlations among PEAK Equivalence Pre-Assessment subtests were line with previous research by Dixon, Belisle, & Stanley (in review), providing additional information for the relationship among measured components of equivalence. These findings have implications for guiding educational and therapeutic intervention, as well as provide additional evidence of the utility of the PEAK Equivalence Module.




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