TABLE 3.

Analysis B: summary of parameters examined for all DRG-matched patients in study and control groups

Parameter	Control group	Study group	Difference between study and control groupsa	SD for study group/ SD for control group	P value	95% confidence interval
No. of patients	190	188	Not applicable
HCFA severity rating	2.5	2.2	0.3	1.9/2.9	0.198	−0.82 to −0.17
Age (yr)	65.6	66.1	+0.5	16.4/19.4	0.764	−3.1 to 4.2
Mortality rate (crude rate) (%)	10.0	11.2	+1.2	Not applicable	0.741	Not applicable
Average length of stay (days)	13.7	11.0	−2.7	10.2/14.0	0.035	−5.1 to −0.19
Average total cost ($)	18,601	13,294	−5,308	14,197/23,625	0.008	−9,248 to −1,368
Average variable cost ($)	8,515	5,889	−2,626	6,714/11,851	0.008	−4,573 to −679
Average variable cost in pharmacy ($)	1,702	1,227	−475	2,151/3,343	0.104	−1,040 to 98
Average variable cost in radiology ($)	328	233	−95	324/495	0.043	−185 to −3

^aNegative and positive numbers indicate a decrease and an increase compared with the value for the study group, respectively.