Table 2.

Descriptive statistics of variables in the LACE (Length of stay, Acuity of the admission, Comorbidity of the patient, and Emergency department use) readmission model (patient encounter level).

Variable	Frequent cohorta, mean (SD)	Standard cohortb, mean (SD)	Geriatrics cohortc, mean (SD)	Combined cohortd, mean (SD)
Age (years)	72.94 (13.24)	67.07 (15.98)	77.62 (8.09)	67.51 (15.87)
Gender (1: Male, 0: Female)	0.50 (0.50)	0.55 (0.50)	0.50 (0.50)	0.54 (0.50)
Length of stay (days)	6.73 (13.18)	5.47 (10.15)	6.65 (10.81)	5.57 (10.41)
Charlson Comorbidity Index	0.47 (1.39)	0.41 (1.18)	0.49 (1.38)	0.42 (1.20)
Emergency department admission (1: Yes, 0: No)	0.50 (0.50)	0.57 (0.50)	0.58 (0.49)	0.56 (0.50)
Intensive care unit stay (1: Yes, 0: No)	0.03 (0.17)	0.05 (0.22)	0.04 (0.21)	0.05 (0.22)
Emergency department visits in last 6 months	2.86 (3.07)	1.39 (2.77)	1.47 (2.44)	1.50 (2.82)

^aPatients identified by the hospital as frequent readmission patients.

^bSample of a typical hospital patient.

^cSubset of patients in the “Standard” sample who are 65 years of age or older.

^dCombination of the “Frequent” and “Standard” samples.