Tehran University of Medical Sciences Iranian Journal of Psychiatry 1735-4587 11 3 2016 10 09 133 139 EN Hamid Zarrabipoor Department of Psychiatry, Tehran University of Medical Sciences, Roozbeh Hospital, Tehran, Iran. Mehdi Tehrani-Doost Department of Psychiatry, Tehran University of Medical Sciences, Roozbeh Hospital, Tehran, Iran.Research Center for Cognitive and Behavioral Sciences, Tehran University of Medical Sciences, Tehran, Iran Zahra Shahrivar Department of Psychiatry, Tehran University of Medical Sciences, Roozbeh Hospital, Tehran, Iran.Research Center for Cognitive and Behavioral Sciences, Tehran University of Medical Sciences, Tehran, Iran 2016 08 23 2016 08 23 Objective: This study evaluated the theory of mind (ToM) in adolescents diagnosed with bipolar disorder ‎‎(BD) during their euthymic period compared to a typically developing (TD) group.‎ Method: The BD group consisted of thirty 11-18 year old inpatients in euthymic phase. The TD ‎group included 30 age, gender, and IQ matched volunteer students. To assess the diagnosis and ‎comorbid disorders, we performed the semi-structured interview of the Kiddie Schedule for Affective Disorders ‎and Schizophrenia-Present and Lifetime Version (K-SADS-PL) for the BD adolescents. To ‎evaluate the severity of attention deficit hyperactivity disorder (ADHD) and mania, Conner's ‎Parent Rating Scale-Revised version (CPRS-R), and Young Mania Rating Scale (YMRS) were ‎used, respectively. Ravens Progressive Matrices was conducted to evaluate intellectual ability in ‎the both groups. Happe Strange Stories test was performed to assess ToM in the participants. Data were ‎analyzed using the independent t-test, analysis of covariance, and Pearson Correlation analysis.‎ Results: The two groups did not show any differences in comprehending the stories; however, the BD ‎group’s mentalizing scores were significantly weaker than the TD group (p<0.05).‎‎ Conclusion: The ToM impairments in adolescents with BD may be explained as a trait marker which may lead ‎to continuation of social problems even during remission‏.‏ https://ijps.tums.ac.ir/index.php/ijps/article/view/771 https://ijps.tums.ac.ir/index.php/ijps/article/download/771/563