1. United Nations (2008) World population prospects: the 2008 revision. Population Division of the Department of Economic and Social Affairs of the United Nations Secretariat. Available at ( http://esa.un.org/unpp/ )
2. Gullberg B, Johnell O, Kanis JA (1997) World-wide projections for hip fractures. Osteoporos Int 7:407–413
3. Cooper C, Campion G, Melton LJ (1992) Hip fractures in the elderly: a worldwide projection. Osteoporos Int 2:285–289
4. Borges-Yanez A (1993) Transición demografica en México. Situación de la población anciana. [Demographic transition of Mexico. Situation of elderly population]. Bol Mens Epidemiol 8:81–88
5. Boletin de Informacion Estadistica (2002) Principales causas de egresos hospitalarios. Principales causas de egresos hospitalarios. 2002 Boletin de Informacion Estadistica II