[1] Univ Tehran Med Sci, Sch Publ Hlth, Dept Epidemiol & Biostat, Tehran, Iran
[2] Shahid Beheshti Univ Med Sci, Res Inst Endocrine Sci, Cellular & Mol Res Ctr, Tehran, Iran
[3] Univ Tehran Med Sci, Osteoporosis Res Ctr, Endocrinol & Metab Clin Sci Inst, Tehran, Iran
[4] Univ Tehran Med Sci, Endocrinol & Metab Res Inst, Tehran, Iran
[5] Bushehr Univ Med Sci, Persian Gulf Biomed Sci Res Inst, Persian Gulf Marine Biotechnol Res Ctr, Bushehr, Iran
[6] Imperial Coll London, Sch Publ Hlth, Dept Biostat & Epidemiol, MRC PHE Ctr Environm & Hlth, London, England