Tehran University of Medical Sciences Iranian Journal of Psychiatry 1735-4587 5 3 2010 09 15 88 92 Mitra Hakim Shooshtary Department of Psychiatry, Iran University of Medical Sciences, Institute of psychiatry, Mental Health Research Center Narges Chimeh Family Research Institute, assistant professor of Shahid Beheshti University Mostafa Najafi Behavioral Science Research Center, Isfahan University of Medical Sciences Mohammad Reza Mohamadi Psychiatry and Psychology Research Center, Tehran University of Medical Sciences Reza Yousefi-Nouraie Psychiatry and Psychology Research Center, Tehran University of Medical Sciences Afarin Rahimi-Mvaghar Health Research Methodology Graduate Program, Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada 2015 10 14 Objectives: Attention-deficit/hyperactivity disorder (ADHD) is the most common neurobehavioral disorder of childhood. Children with ADHD may experience significant functional problems. Our objective was to examine the prevalence of ADHD and its subtypes in Iran. Methods: Pubmed, ISI web of science, psychinfo, Iranpsych, Iranmedex, Irandoc were searched. Irandoc, Iranmedex and Iranpsych are Iranian databases of which the last one is especially for psychiatry and psychology literature. INCLUSION CRITERIA WERE: conducting studies by random sampling, using valid instruments to assess ADHD diagnosis or symptoms,and presenting a prevalence of ADHD or attention deficit and / or hyperactivity symptoms. Results: After quality assessment, 16 studies were accepted. Their estimation of prevalence was different as different scales were used. Hyperactive type was more prevalent in boys, and inattentive type was more prevalent in girls. Conclusion: Being aware of the epidemiology of ADHD in Iran helps us to make improvements in planning the allocation of funds for mental health services. Using one instrument in studying the prevalence of ADHD in a population may lead to more precise estimations. https://ijps.tums.ac.ir/index.php/ijps/article/view/367 https://ijps.tums.ac.ir/index.php/ijps/article/download/367/363