fa عمومى General پژوهشي Research <strong>Introduction</strong>: The aim of this study was to evaluate the sensitivity and specificity of history and physical examination in the diagnosis of pneumothorax and hemotorax in blunt chest trauma patients.<br> &nbsp;<br> <strong>Methods</strong>: This was a descriptive-analytical study. Physical examination results were compared with findings of chest CT, X-ray, and ultrasound diagnostic methods using ROC curves in SPSS software.<br> &nbsp;<br> <strong>Findings</strong>: Three (3.03) patients with pneumothorax and 7 (7.07) patients with hemotrax were found among 99 patients with mean age of 33.4&plusmn;19.43. The highest sensitivity was due to chest scraping for pneumothorax (66.67%) and hemothorax (100%). The highest specificity was for abnormal lung sounds (Crackle), with 96.88% specificity for pneumothorax and 98.89% specificity for hemothorax. In the study of pneumothorax, the highest PPV and NPV were related to pulmonary sound reduction (12.5% and 98.7%, respectively). In the hemothorax evaluation, the highest PPV was related to chest tenderness (37.5%) and the highest NPV to pulmonary sound reduction (96.3%). The highest accuracy for pneumothorax was for pulmonary sound reduction and abnormal pulmonary sounds for hemothorax. A heart rate above 98.5 was associated with pneumothorax with a sensitivity of 17.6% and a specificity of 66.7%. Diastolic blood pressure below 70.5 with 46.9% sensitivity and 85.7% specificity and respiratory rate below 6.5 with 92.6% sensitivity and 57.1% specificity were associated with hemothorax.<br> &nbsp;<br> <strong>Conclusion: </strong>Proper physical examination and history taking can help to diagnose hemothorax and pneumothorax with high sensitivity and specificity complementarity to CT scan or X-ray results. Physical Examination, Pneumothorax, Hemothorax 60 68 http://intjmi.com/browse.php?a_code=A-10-1-294&slc_lang=fa&sid=1 Samaneh Abiri 10031947532846003366 10031947532846003366 Yes Department of Emergency Medicine, Jahrom University of Medical sciences, Jahrom, Iran. Naser Hatami 10031947532846003367 10031947532846003367 No Student Research Committee, Jahrom University of Medical Sciences, Jahrom, Iran. Seyed Reza Habibzadeh 10031947532846003368 10031947532846003368 No Department of Emergency Medicine, Faculty of Medicine, Mashhad University of Medical sciences, Mashhad, Iran. Neema John Mehramiz 10031947532846003369 10031947532846003369 No Department of Psychiatry Neurology. Banner university medical center, Tucson, AZ, USA. Hossein Yaghoubian 10031947532846003370 10031947532846003370 No Department of Emergency Medicine, Mashhad University of Medical sciences, Mashhad, Iran. Navid Kalani 10031947532846003371 10031947532846003371 No Anesthesiology, Critical care and pain management research center, Jahrom University of Medical Sciences, Jahrom, Iran. Mojtaba Ghaedi 10031947532846003372 10031947532846003372 No Assistant Professor of Surgery, Department of Surgery, School of Medicine, Jahrom University of Medical Sciences, Jahrom, Iran.