en Psychology Psychology Original Research: Clinical Science Original Research: Clinical Science <p> <strong> Background: </strong>The effect of psychosocial work environment on personal and organizational aspects of employees is well-known and it is of fundamental importance to have valid tools to evaluate them. This study aims to evaluate the reliability and validity of the Persian version of Copenhagen Psychosocial Questionnaire (COPSOQ). </p><p> <strong> Methods </strong>: The questionnaire was translated into Persian and then back translated into English by two translators separately. The wording of the final Persian version was established by comparing the translated versions with the original questionnaire. One hundred three health care workers completed the questionnaire. Chronbach’s alpha was calculated, and factor analysis was performed. </p><p> <strong> Results </strong>: Factor analysis revealed acceptable validity for the five contexts of the questionnaire. Cronbach’s alpha ranged from 0.73 to 0.82 in different contexts. </p><p> <strong> Conclusion </strong>: This study revealed that the Persian version of COPSOQ is a reliable and valid instrument for measuring psychosocial factors at work. </p><p>  </p> Occupational Health, Validity, Reliability, Iran, Psychosocial Work Environment. 498 502 http://mjiri.iums.ac.ir/browse.php?a_code=A-10-1-845&slc_lang=en&sid=1 Omid Pournik pournik.o@iums.ac.ir 200319475328460016789 200319475328460016789 No Department of Community Medicine, School of Medicine, Iran University of Medical Sciences, Tehran, Iran. Leila Ghalichi ghalichi.l@iums.ac.ir 200319475328460016790 200319475328460016790 Yes Mental Health Research Center, Iran University of Medical Sciences, Tehran, Iran. Alireza Tehrani Yazdi alireza_tehraniy@aut.ac.ir 200319475328460016791 200319475328460016791 No Medical Radiation Department, Faculty of Energy Engineering and Physics, Amirkabir University of Technology, Tehran, Iran. Seyed Mohammad Tabatabaee mtjabali@yahoo.com 200319475328460016792 200319475328460016792 No Department of Nutrition, School of Public Health, Iran University of Medical Sciences, Tehran, Iran. Mostafa Ghaffari mostafa.ghaffari@medsci.uu.se 200319475328460016793 200319475328460016793 No and Occupational Medicine Research Center, School of Medicine, Iran University of Medical Sciences, Tehran, Iran, & Occupational and Environmental Medicine, Department of Medical Sciences, Uppsala University Hospital, S-751 85 Uppsala, Sweden. Eva Vingard eva.vingard@medsci.uu.se 200319475328460016794 200319475328460016794 No Occupational and Environmental Medicine, Department of Medical Sciences, Uppsala University Hospital, S-751 85 Uppsala- Sweden.