The objective of this study is to evaluate the differential efficacy between Mindfulness-Based Cognitive Therapy (MBCT) and Cognitive Behavioral Therapy (CBT). A quasi-experimental design of repeated measures before and after the test (n = 57) was used with a non-equivalent control group from a previous cohort treated with CBT (n = 105). The t-test revealed significant differences in subjective quality of life for the MBCT group, and in quantity, optimum, and adequate sleep for the CBT group. The pre-post effect size comparison mostly showed slightly larger effect sizes in the MBCT group. CBT and MBCT had comparable efficacies, although a slight trend towards larger effect sizes in MBCT was found. Likewise, CBT seemed to improve sleep-related variables, while MBCT was associated with improvements in pain and quality of life.
Keywords: CBT; MBCT; chronic pain; differential efficacy; effect sizes.