[1] Univ Nacl Autonoma Mexico, Fac Med, CMN Siglo 21, IMSS,Clin Epidemiol Unit, Mexico City 11000, DF, Mexico
[2] Unidad Diagnost Osteoporosis, Mexicali, Baja California, Mexico
[3] Hosp Los Angeles, Puebla, Mexico
[4] CEDOES Diagnost & Pesquisa Vitoria ES, Rio Piedras, Brazil
[5] Univ Puerto Rico, Dept Med, Div Endocrinol Diabet & Metab, San Juan, PR 00936 USA
[6] Univ Salvador, Fac Med, Inst Invest Metab, Buenos Aires, DF, Argentina
[7] Univ Libre Bruxelles, Fac Med, Hosp Metropolitano, Barranquilla, Colombia
[8] Univ Calif San Francisco, Dept Epidemiol & Biostat, San Francisco, CA 94143 USA
[9] UAEMex, Ctr Invest Ciencias Med, CMN Siglo 21, IMSS,Clin Epidemiol Unit, Mexico City, DF, Mexico
[10] Cosme Argerich Hosp, Dept Rheumatol, Buenos Aires, DF, Argentina
[11] Hosp Aranda Parra, Osteoporosis Unit, Leon, Spain
[12] Inst Mexicano Seguro Social, Unidad Invest Epidemiol, Mexico City, DF, Mexico
[13] Hosp Gen Zona Numero 15, Inst Mexicano Seguro Social, Reynosa, Tamaulipas, Mexico
[14] Univ Puerto Rico, Grad Sch Publ Hlth, Dept Biostat & Epidemiol, San Juan, PR 00936 USA
[15] Calif Pacific Med Ctr, Res Inst, San Francisco Coordinating Ctr, San Francisco, CA USA
[16] Univ Calif San Francisco, San Francisco, CA 94143 USA
[17] Sch Med, CIRO Med Ctr, Buenos Aires, DF, Argentina
[18] Inst Mexicano Seguro Social, Serv Salud, Mexico City, DF, Mexico