In a study of the duration of antibiotic prophylaxis in elective surgery, 466 procedures were surveyed over a four-year period. It is difficult to prove the efficacy of antibiotic prophylaxis when the rate of infection is so low, and, although not statistically significant, there is no difference in the infection rate whether the antibiotics are given intraoperatively only or for 48 hours, three days, or seven days. Per 100,000 patients, the cost savings of giving antibiotics intraoperatively rather than for 48 hours would have been $7,700,000; with the reduction from seven days to one-dose antibiotics, the savings would have been $29,700,000.