Table 1.

Demographics and other Characteristics of the Medicare Elderly Population

Characteristic	Total (%) N = 1,493,441	CDI Cases N = 174,903 n (%)	Controls N = 1,318,538 n (%)
Age (mean, SD)	77.5 (7.9)	80.5 (8.0)	77.1 (7.7)
Female	925,316 (62.0)	112,251 (64.2)	813,065 (61.7)
Race
White	1,301,397 (87.1)	153,857 (88.0)	1,147,540 (87.0)
Black	110,870 (7.4)	13,801 (7.9)	97,069 (7.4)
Other race	81,174 (5.4)	7,245 (4.1)	73,929 (5.6)
Prior LTCF residence	95,775 (6.4)	40,143 (23.0)	55,632 (4.2)
Dually eligible for Medicare and Medicaid	271,128 (18.2)	56,376 (32.2)	214,752 (16.3)
Acute care hospitalization in past year	404,227 (27.1)	148,066 (84.7)	256,161 (19.4)
Short-term skilled nursing facility encounter in past year	183,539 (12.3)	93,595 (53.5)	89,944 (6.8)