1. Ebrahim S, Kalache A, eds. Epidemiology of Old Age. London: British Medical Journal Publications; 1995.
2. U.S. Department of Health & Human Services. Health United States, 1992. Hyattsville, MD: USDHHS; 1993.
3. Boult C, Dowd B, McCaffrey D, et al. Screening elders for risk of hospital admission. J Am Geriat Soc. 1993;41: 811–817.
4. Wolinsky FD, Johnson RJ. The use of health services by older adults. J Gerontol Soc Sci. 1991; 46 (6): S345 - S357.
5. Narain P, Rubenstein LZ, Wieland D, et al. Predictors of. immediate and 6-month outcomes in hospitalized elderly patients: the importance of functional status. J Am Geriatr Soc. 1988; 36: 775–783.