Study designs of evaluations included in the review
Randomised controlled trials (RCTs) were eligible for inclusion in the review. In the included studies, the duration of follow-up ranged from 10 days to 6 weeks.
Specific interventions included in the review
Studies that compared pre-operative antibiotics with placebo were eligible for inclusion. Studies could also use post-operative prophylactic antibiotics. The included studies evaluated a variety of peri-operative antibiotics (cefonicid, cefazolin, azithromycin and amoxicillin-clavulanate); in one study, antibiotics were also given post-operatively.
Participants included in the review
Studies of adults (older than 18 years) undergoing breast surgery for benign or malignant disease were eligible for inclusion. Data for eligible patients undergoing breast surgery were extracted from studies that included patients undergoing other types of surgery. Most (85%) of the participants in the included studies were undergoing surgery for malignant disease. The patients were undergoing a variety of operations, such as lumpectomy and mastectomy with and without axillary lymph node dissection.
Outcomes assessed in the review
Studies that assessed wound infection or adverse reactions to the antibiotics were eligible for inclusion in the review.
How were decisions on the relevance of primary studies made?
Two reviewers independently selected studies for inclusion.