Table 2.

Results of qualitative cultures of the external graft surface and quantitative sonication cultures of the internal graft surface after 72 h of incubation (Experiment 1).

Experiment number	MRSA		Escherichia coli
	External surface	Internal surfacea,b	External surface	Internal surfacea,b
1	0	2.9 × 105	0	1.23 × 105
2	0	6.4 × 103	0	3.1 × 106
3	0	7 × 104	0	1.5 × 107
4	0	5.9 × 103	0	7 × 106
5	0	2.2 × 104	0	3.5 × 105
6	0	1.6 × 104	0	1.9 × 105

^aEach observation represents the median colony count for three sections of a unique graft.

^bTwo-sided Fisher’s exact test p < 0.01 for comparison of bacterial colony counts obtained from the internal and the external graft surfaces.