KMAN Publication Inc. (KMANPUB) Journal of Adolescent and Youth Psychological Studies (JAYPS) 2981-2526 7 Serial Number 46 2026 07 10 Development of a Model of Obsessive–Compulsive Symptoms Based on Thought–Action Fusion and Emotion Regulation: The Mediating Role of Intolerance of Uncertainty among University Students in Kermanshah Development of a Model of Obsessive–Compulsive Symptoms Based on Thought–Action Fusion and Emotion Regulation: The Mediating Role of Intolerance of Uncertainty among University Students in Kermanshah 1 13 10.61838/ EN Journal Article 2025 12 14 <table> <tbody> <tr> <td> <p><strong>Objective:</strong>  This study aimed to examine a structural model of obsessive–compulsive symptoms based on thought–action fusion and emotion regulation strategies, with the mediating role of intolerance of uncertainty.</p> <p><strong>Methods and Materials: </strong>The study employed an applied, descriptive–correlational design with a cross-sectional approach. The statistical population comprised all students enrolled in universities in Kermanshah during the second semester of the 2024–2025 academic year. A total of 200 students were selected using convenience sampling. Data were collected using the Padua Inventory for obsessive–compulsive symptoms, the Thought–Action Fusion Questionnaire, the Emotion Regulation Questionnaire (cognitive reappraisal and expressive suppression), and the Intolerance of Uncertainty Scale. Data analysis was conducted using SPSS (version 21) and SmartPLS (version 3). Partial least squares structural equation modeling was applied to evaluate the measurement and structural models, assess model fit, and test direct and indirect relationships among the study variables.</p> <p><strong>Findings: </strong>The results indicated a positive and significant direct effect of thought–action fusion on obsessive–compulsive symptoms (β = 0.17, p &lt; .05) and a negative and significant direct effect of cognitive reappraisal on obsessive–compulsive symptoms (β = −0.26, p &lt; .01). Intolerance of uncertainty showed a strong positive direct effect on obsessive–compulsive symptoms (β = 0.39, p &lt; .01). Mediation analyses revealed that intolerance of uncertainty significantly mediated the relationship between thought–action fusion and obsessive–compulsive symptoms (β = 0.15, p &lt; .01), as well as the relationship between expressive suppression and obsessive–compulsive symptoms (β = 0.12, p &lt; .01). The overall structural model demonstrated acceptable fit and predictive relevance.</p> <p><strong>Conclusion: </strong>The findings support an integrative cognitive–emotional model in which maladaptive thought–action fusion beliefs and emotion regulation patterns contribute to obsessive–compulsive symptoms directly and indirectly through intolerance of uncertainty.</p> </td> </tr> </tbody> </table> <p> </p> https://www.journals.kmanpub.com/index.php/jayps/article/download/5080/10163