1. Non‐Communicable Diseases Research Center, Endocrinology and Metabolism Population Sciences Institute Tehran University of Medical Sciences Tehran Iran
2. Department of Biostatistics University of Social Welfare and Rehabilitation Sciences Tehran Iran
3. Division of Gastroenterology, Department of Medicine Duke University Durham North Carolina USA
4. Endocrinology and Metabolism Research Center, Endocrinology and Metabolism Clinical Sciences Institute Tehran University of Medical Sciences Tehran Iran