1. Department of General Surgery, Clinical Research and Development Center at Shahid Modarres Hospital; Shahid Beheshti University of Medical Sciences; Tehran Iran
2. Critical Care Quality Improvement Research Center; Shahid Beheshti University of Medical Sciences; Tehran Iran
3. Department of Epidemiology and Biostatistics; Tehran University of Medical Sciences; Tehran Iran
4. Non-Communicable Research Center; Alborz University of Medical Sciences; Karaj Iran