Silver Book Fact
A study that looked at a combination of calcium and Vitamin D found that hip fractures were reduced by around 43%.
Chapuy M, Arlot M, Duboeuf F, Brun J, et al. Vitamin D3 and Calcium to Prevent Hip Fractures in the Elderly Women. NEJM. 1992; 327(23): 1637-42. http://content.nejm.org/cgi/content/abstract/327/23/1637