1. Research Institute for Infectious Diseases of Digestive System; School of Medicine; Ahvaz Jundishapur University of Medical Sciences; Ahvaz Iran
2. Department of Epidemiology and Biostatistics; Faculty of Health; Ahvaz Jundishapur University of Medical Sciences; Ahvaz Iran
3. Department of Internal Medicine; Imam Khomeini Hospital; Ahvaz Jundishapur University of Medical Sciences; Ahvaz Iran