KMAN Publication Inc. (KMANPUB) KMAN Counseling & Psychology Nexus 3041-9026 In Press 2027 01 01 Comparison of the Effectiveness of Rumination-Focused Cognitive Behavioral Therapy and Classical Cognitive Behavioral Therapy on Rumination and Positive Beliefs About Rumination in Individuals With Obesity: A Single-Case Multiple-Baseline Study Comparison of the Effectiveness of Rumination-Focused Cognitive Behavioral Therapy and Classical Cognitive Behavioral Therapy on Rumination and Positive Beliefs About Rumination in Individuals With Obesity: A Single-Case Multiple-Baseline Study 1 14 EN Journal Article 2026 06 10 <p>The present study aimed to compare the effectiveness of rumination-focused cognitive behavioral therapy and classical cognitive behavioral therapy in reducing rumination and positive beliefs about rumination among individuals with obesity. The study employed a single-case experimental design using a multiple-baseline design across participants. Following screening, six adults with obesity were randomly assigned to two treatment conditions, with three participants in each condition. Baseline phases included four to six measurement points, the intervention phase included eight measurement points, and the follow-up phase included four measurement points. Both interventions were delivered in ten weekly 60-minute sessions; the eight assessment occasions during the intervention phase did not correspond one-to-one with the ten treatment sessions. Rumination was assessed using the Ruminative Responses Scale, and positive beliefs were assessed using the nine-item Positive Beliefs About Rumination Scale. Data were analyzed using visual analysis, percentage improvement, and the Nonoverlap of All Pairs (NAP) and Tau-U indices. The mean of the final two baseline data points in both groups was 76 for rumination and 32 for positive beliefs. At posttreatment, the percentage improvement in rumination was 24.6% in classical cognitive behavioral therapy and 52.7% in rumination-focused cognitive behavioral therapy; at follow-up, these values were 21.7% and 51.8%, respectively. For positive beliefs, posttreatment improvement was 23.9% and 61.5% for the two approaches, respectively, and follow-up improvement was 20.3% and 59.4%, respectively. In comparisons of baseline with intervention, NAP for rumination was near the ceiling in both treatments, whereas Tau-U slightly favored classical cognitive behavioral therapy. In contrast, both indices for positive beliefs favored rumination-focused cognitive behavioral therapy. Individual graphs indicated that reductions in positive beliefs began earlier in the rumination-focused condition and were followed shortly thereafter by an accelerated reduction in rumination. Final score levels, improvement percentages, and visual patterns in this sample favored rumination-focused cognitive behavioral therapy, particularly for positive beliefs about rumination. However, the limited inconsistency in the Tau-U index for rumination indicates that conclusions should be based on convergence across multiple indicators and interpreted cautiously.</p> https://www.journals.kmanpub.com/index.php/psychnexus/article/download/6157/11738