Study	Reason for exclusion
Abo‐Rahmy 1998	NOT RANDOMIZED. A total of 1524 consecutive hernia patients, divided in 3 groups: A) 606 with ceftriaxone, B) 408 with pefloxacine, C) 510 with several cefalosporins or quinolones different from the A and B groups. One single patient with infection was observed (0,06%).
Angio 2001	UNCONTROLLED TRIAL. Single arm with antibiotic prophylaxis. 112 patients submitted to prosthetic hernioplasty by anterior approach (94 cases) and by transabdominal preperitoneal laparoscopy (18 cases), received levofloxacin 500 mg IV 30 minutes before the surgical operation and 500 mg os in seven days following. Infection rate was zero.
Barreca 2000	RETROSPECTIVE. Study developed in two hospitals, one arm by hospital. Administers cefotaxime 2 gr IV 30' before surgery. A total of 147 patients, 63 with prophylaxis and 84 without; 87% with hernioplasty . Both hospitals show an infection rate of zero.
Dazzi 1994	UNCONTROLLED TRIAL. Single arm with antibiotic prophylaxis. Patients with several pathologies; can be identified 189 hernia patients (100 herniorraphy, 89 hernioplasty), prophylaxis with teicoplanin. Infection rate: zero.
Deysine 2005	UNCONTROLLED TRIAL. Single arm with antibiotic prophylaxis in ventral and inguinal herniorrhaphies. The patients received cefazolin 1 hour before surgery plus frequent wound irrigations with a solution of 80 mg of gentamycin sulphate dissolved in 250 ml of normal saline solution. Infection rate: 0.11% in over 4.000 herniorrhaphies.
Dixon 2006	DOES NOT INCLUDE HERNIA PATOHOLOGY.
Escartín 1999	RETROSPECTIVE. Study with 475 patients. In 277 prosthetic material is used: 144 with antibiotic prophylaxis (3 infected) and 133 with placebo (10 infected). In 198 patients no prosthetic material was used: 14 with antibiotic prophylaxis (0 infected) and 184 with placebo (13 infected). They recommend prophylaxis when using prosthetic material.
Esposito 2006	INCOMPLETE DATA. Prospective randomised trial. The objective of the study is prophylaxis in hernia repair and breast surgery. There were 350 patients underwent to hernia repair, 168 y 162 patients in the prophylaxis and placebo group. Data of infected patients undergoing hernia repair are not provided by the author.
Gervino 2000	UNCONTROLLED TRIAL. Single arm with antibiotic prophylaxis. 1254 patients intervened with prosthetic material, received ceftriaxone IV 2 gr before surgery. Infection rate assessed retrospectively: zero .
Gilbert 1993	RETROSPECTIVE. Large series, that presents methodologic handicaps. Infection rate: a)primary herniorraphy: 1.1% without prophylaxis and 1.3% with prophylaxis; b) primary hernioplasty: 0.34% without prophylaxis and 0.98% with prophylaxis; c) herniorraphy for recurrent hernia: 0% in both groups; d) hernioplasty for recurrent hernia: 2.2% without prophylaxis and 0.43% with prophylaxis. They do not recommend antibiotic prophylaxis on surgery for hernia repair.
Gilmore 1977	PROPHYLAXIS WITH ANTISEPTIC TREATMENT.
Hair 2000	RETROSPECTIVE. Multicentric trial where 71% of 5.506 patients received antibiotic prophylaxis. Global infection rate: 8%, without significant differences between patients with and without antibiotic prophylaxis (RR 0.9, IC95% 0.7 ‐ 1.1). Individualized infection rate is not provided for each group. They recommend not to administer antibiotic prophylaxis.
Hedawoo 1995	REVIEW. In a study of clean surgical techniques, 134 hydroceles and hernias are included, without antibiotic prophylaxis. Infection rate 3,6%.
Houck 1989	INCOMPLETE DATA. The objective of the study is prophylaxis in incisional hernia and patients with inguinal hernia constitute the control group. Data for these patients is not provided.
Karran 1992	INCOMPLETE STUDY. No results provided.
Kuzu 2005	BOTH STUDY ARMS RECEIVED PROPHYLAXIS. A total of 408 patient were enrolled in a prospective randomised study which compare the efficacy of oral versus parenteral prophylactic amoxicillin‐clavulanic acid in open mesh hernia repair. Infections rates: 0,5% and 1,5%, respectively.
Lewis 1995	INCOMPLETE DATA. Prospective, randomised, well‐designed study on clean surgical techniques. A total of 165 patients had hernia repair (86 receiving cefotaxime 2 gr IV prior to surgery and 79 receiving placebo), but there's no information on the number of infections on these patients. INCOMPLETE DATA. Prospective, randomised, well‐designed study on clean surgical techniques. A total of 165 patients had hernia repair (86 receiving cefotaxime 2 gr IV prior to surgery and 79 receiving placebo), but there's no information on the number of infections on these patients.
Massaioli 1995	UNCONTROLLED TRIAL. Single arm of antibiotic prophylaxis with vancomycin on patients with incisional hernia or inguinal hernia repair with prosthetic material. Infection rate: 1/40 patients (2,5%).
Musella 2001	BOTH STUDY ARMS RECEIVED PROPHYLAXIS. Both groups received prophylaxis with a systemic antibiotic. Intervention group, additionally, is administered a collagen sponge impregnated with gentamicin. Infection rate: 6/284 patients on control group and 1/293 patients on prophylaxis group (OR=0.16; IC95% 0.02‐1.33).
Nundy 1983	INCOMPLETE DATA. Study on clean surgical techniques, not possible to obtain data of patients with hernia repair. Prophylaxis is penicillin 2 to 12 hours prior to the surgery.
Platt 1992	NOT RANDOMISED. Study developed with the patients not included on the published 1990 trial. A total of 1221 patients with herniorraphy. Infection rate: 2/239 patients on prophylaxis, and 15/982 patients without prophylaxis (OR 0.54; IC95% 0,06‐2,07; P= 0.4). They recommend prophylaxis only for high risk patients.
Praveen 2009	BOTH STUDY ARMS RECEIVED PROPHYLAXIS. A single blinded prospective randomised trial with locally applied gentamicin against systemic gentamicin in 202 patients underwent to Lichtenteins tension free repair. There were seven SSI in each arm.
Reggiori 1996	BOTH STUDY ARMS RECEIVED PROPHYLAXIS. Prospective randomised trial, well designed, administering a single dose of ampicillin 2 gr IV at induction of anaesthesia in one arm and fortified procaine 1,2 megaunits/24 hr IM daily for seven days starting about 3 hr after surgery on the other arm. Infection rate: 0/123 patients on ampicillin and 8/106 patients on penicillin (OR = 0,05; IC 95% 0,0 ‐ 0,82).
Ryan 1967	NOT RANDOMISED. Non homogeneous groups: control group with majority of patients on local anaesthesia, prophylaxis group with majority of patients on general anaesthesia. Children are included on the trial. Control group is sequential in time to the intervention group. Each group is intervened in a different hospital. Infection rate: 82/5335 patients in control group, 2/1183 patients in penicillin group. (OR 0.11; IC95% 0.03‐0.44)
Shwed 1991	BOTH STUDY ARMS RECEIVED PROPHYLAXIS. Study of several surgical techniques to evaluate the efficacy of a new antibiotic compared to an already established one. A total of 128 patients, 5 of whom had hernia repair.
Spallitta 1999	UNCONTROLLED TRIAL. Single arm of 100 patients receiving antibiotic prophylaxis and prosthetic material.
Sultan 1989	BOTH STUDY ARMS RECEIVED PROPHYLAXIS.
Terzi 2005	BOTH STUDY ARMS RECEIVED PROPHYLAXIS. Prospective randomised study which compare the efficacy of oral ciprofloxacin versus parenteral cefazolin in open mesh hernia repair. Infections rates: 2% in both arms.
Van‐Damme 1981	NOT RANDOMISED. Technical review using different types of antibiotics, both intravenous and topical.
Vara 1993	MISBALANCES IN TREATMENT BETWEEN GROUPS: Patients with hernioplasty received prophylaxis while patients with herniorraphy received placebo . Patients infected: 2/141 patients on prophylaxis and 9 /137 patients on placebo. They recommend antibiotic prophylaxis to all patients.
Wantz 1996	RETROSPECTIVE SERIE. Serie of 1076 patients followed for 6 years. Administers local anaesthesia and prosthetic material (Lichtentein and Gilbert), without antibiotic prophylaxis. One single patient with infection (0,09%).