Table 1.

Vancomycin MICs for Staphylococcus aureus by Etest at Alfred I. DuPont Hospital for Children, 1 April 2000 to 31 March 2008

Years	Values for:
	All isolates			MSSA			MRSA
	n	Geometric mean MIC (μg/ml) (±SD) (P = 0.146a)	Mode (μg/ml)	n (%)	Geometric mean MIC (μg/ml) (±SD) (P = 0.364b)	Mode (μg/ml)	n (%)	Geometric mean MIC (μg/ml) (±SD) (P = .425c)	Mode (μg/ml)
2000–2001	46	1.04 (±0.36)	1	43 (94)	1.05 (±0.36)	1	3 (6)	1.4 (±0.38)	0.75
2001–2002	55	1.04 (±0.37)	1	50 (91)	1.02 (±0.35)	1	5 (9)	1.35 (±0.41)	1
2002–2003	73	1.17 (±0.32)	1	68 (93)	1.2 (±0.31)	1	5 (7)	1.35 (±0.41)	1
2003–2004	50	0.98 (±0.29)	1	40 (80)	1 (±0.29)	1	10 (20)	0.86 (±0.26)	0.75
2004–2005	59	1.32 (±0.3)	1.5	51 (86)	1.3 (±0.29)	1.5	8 (24)	1.45 (±0.37)	1.5
2005–2006	56	0.78 (±0.37)	1	42 (75)	0.74 (±0.32)	0.5	14 (25)	0.9 (±0.46)	1
2006–2007	51	1.04 (±0.42)	1	35 (69)	0.98 (±0.42)	1.5	16 (31)	1.19 (±0.39)	1
2007–2008	46	1.44 (±0.37)	1.5	34 (74)	1.45 (±0.34)	1.5	12 (26)	1.4 (±0.46)	1.5
Total	436	1.08 (±0.39)	1	363 (93)	1.1 (±0.38)	1	73 (17)	1.2 (±0.44)	1

^aSlope (SE) = 2.012 (0.008).

^bSlope (SE) = 2.008 (0.009).

^cSlope (SE) = 2.018 (0.022).