Table 1.

RCT comparing prophylaxis versus nonprophylaxis antibiotics in inguinal hernia surgery

Author	Prophylaxis Total n	Infection prophy laxis (%)	Nonprophylaxis Total n	Infected nonprophylaxis (%)	RRA CI 95%	NNT	Level of evidence
Open hernia surgery included in Cochrane
Evans et al. (1973) [16]	48	2.1	49	4.1	2 (−4.9, 8.9)	50	3b
Anderson et al. (1980) [17]	137	3.6	150	4	0.4 (−4.1, 4.7)	285	2b
Platt et al. (1990) [18]	301	1.3	311	1.9	0.6 (−1.4, 2.6)	167	1b
Lazhortes et al. (1992) [19]	155	0	153	4.6	4.6 (1.2, 7.9)	22	2b
Taylor et al. (1997) [20]	283	8.8	280	8.9	0.1 (−4.6, 4.7)	1057	1b
Morales et al. (2000) [21]	237	1.7	287	2.1	0.4 (−1.9, 2.7)	248	1b
Yerdel et al. (2001) [22]	136	0.7	133	9	8.3 (3.2, 13.4)	12	2b
Oteiza et al. (2004) [23]	124	0.8	123	0	−0.8 (−2.4, 0.7)	124	2b
Aufenacker et al. (2004) [24]	475	1.7	472	1.9	0.2 (−1.5, 1.9)	449	1b
Celdan et al. (2004) [25]	50	0	49	8.1	8.2 (0.5, 15.8)	12	2b
Pessaux et al. (2005) [5]	2008	3.4	394	5.1	1.7 (−0.6, 4)	59	2b
Perez et al. (2005) [26]	174	1.7	176	3.4	1.7 (−1.6, 5)	59	2b
Total	4,128	2.9	2577	3.9	1.1 (0.2, 2)	92
Laparoscopic hernia surgery not included in Cochrane
Schwetling and Bärlehner (1998) [14]	40	0	40	0	ns		2b
Open hernia surgery not included in Cochrane
Tzovaras et al. (2007) [15]	193	2.6	193	4.4	p = 0.4		2b