en رويكرد شناختي رفتاري Cognitive behavioral پژوهشي Original Research Article <p style="text-align: justify;"><strong>Objective:</strong>This study aimed to differentiate illness anxiety and generalized anxiety by the role&nbsp;of metacognition and intolerance of uncertainty.<br> <strong>Methods:</strong> This research was a descriptive-correlational study with an ex post facto design. The&nbsp;study population included all students of Yazd University, and the study sample comprised 400&nbsp;healthy adult university students (Mean age=23.3 years, SD=4.9) who were selected using&nbsp;the convenience sampling method. Participants were asked to fill out 4 self-report measures:<br> short health anxiety inventory, intolerance of uncertainty scale, metacognitions questionnaire, and Penn State Worry questionnaire. Finally, 338 questionnaires were statistically analyzed by&nbsp;SPSS 20, using ANOVA and discriminant function analysis.<br> <strong>Results:</strong> The results showed that there were significant differences between different groups&nbsp;with respect to most studied variables and that intolerance of uncertainty cannot discriminate&nbsp;between 2 disorders. We can argue that this factor is a significant risk factor in both illness&nbsp;anxiety and generalized anxiety disorders.<br> <strong>Conclusion:</strong> In general, transdiagnostic factors such as intolerance of uncertainty and cognitive&nbsp;beliefs have significant roles in emotional disorders, and can be considered as therapeutic&nbsp;targets.</p> Metacognition, Comorbidity, Anxiety disorders, Diagnosis 57 65 http://jpcp.uswr.ac.ir/browse.php?a_code=A-10-319-1&slc_lang=en&sid=1 Amin Khaje Mansoori maryamkamie@gmail.com No Department of School Psychology, Faculty of Psychology and Education, University of Tehran, Tehran, Iran. Parvaneh Mohammadkhani No Department of Clinical Psychology, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran. Mahdi Mazidi No Department of Clinical Psychology, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran. Maryam Kami maryamkamie@gmail.com Yes Department of Clinical Psychology, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran. Mojgan Bakhshi Nodooshan No Department of Clinical Psychology, Faculty of Humanities, Yazd Branch, Islamic Azad University, Yazd, Iran. Shokooh Shahidi No Department of Clinical Psychology, Faculty of Medicine, Kashan University of Medical Science, Kashan, Iran.