Antibiotic prophylaxis for transperineal prostate biopsy? An unanswered question

• Published in: The Lancet infectious diseases Vol. 22; no. 12; p. 1662
• Main Authors: Singhal, Udit, Qi, Ji, Daignault-Newton, Stephanie, George, Arvin K
• Format: Journal Article
• Language: English
• Published: United States Elsevier Ltd 01.12.2022; Elsevier Limited
• Subjects: Anti-Bacterial Agents - therapeutic use; Antibiotic Prophylaxis; Antibiotics; Biopsy; Chi-square test; Disease prevention; Humans; Infections; Infectious diseases; Male; Prophylaxis; Prostate; Prostate - pathology; Prostatic Neoplasms - diagnosis; Prostatic Neoplasms - drug therapy; Prostatic Neoplasms - pathology; Retrospective Studies; Sepsis; Statistical tests
• ISSN: 1473-3099; 1474-4457; 1474-4457
• DOI: 10.1016/S1473-3099(22)00738-1

Because rates of infection were similar in men with and without prophylaxis in this trial population, the authors concluded that omission of antibiotic prophylaxis might be reasonable. Furthermore, a necessary feature of non-inferiority studies is that the non-inferiority limit cannot exceed the smallest effect size of an active treatment that would be expected compared with a placebo control.3 Given the low infection rates without antibiotic prophylaxis post-transperineal biopsy in the literature (0·1–0·5%),2 selection of a margin of 4% for demonstration of non-inferiority with antibiotic prophylaxis in this setting is further invalidated and leaves the current study substantially underpowered. [...]although the authors use Pearson's χ2 test for testing non-inferiority of two proportions, the recommended statistical test in this scenario is the Farrington-Manning test,4 which further subjects the study to sample size underestimation.