Table 5. Antibiotics given by Case/Control status*.

	Case	Control	P-value* ‡
Average total days of antibiotic therapy	32.3	23.6	0.08‡
Average number of different antibiotics patients received	2.9	2.9	-
Number of patients receiving vancomycin	46	52	0.73*
Number of patients receiving vancomycin in first 5 days	41	39	0.29
Average Total days of vancomycin therapy	14.5	8.4	0.07 ‡
Number of patients receiving cefazolin or nafcillin	12	32	0.004 adjusted
Number of patients receiving cefazolin or nafcillin in first 5 days	8(15.7%)	13(23.2)	0.46

* The differences in proportions between cases and controls were tested among patients receiving vancomycin, vancomycin in the first five days, cefazolin or nafcillin, and cefazolin or nafcillin in the first five days using a chi-square test across the four treatment groups and one control group. The number of cases receiving cefazolin or nafcillin were significantly less than the number of controls, padj 0.004, 95% CI [-0.53,-0.14], adjusting for multiple comparisons. The days of antibiotic therapy among cases and controls were tested as counts using a negative binomial regression model‡ with treatment groups entered as a set of dummy (0,1) variables with the control group as the reference. No statistical difference in days of therapy was found (all p-values > 0.05).