Kaplan-Meier curves and estimates of survival are the most common way to present survival data in medicine, especially for cohorts with different lengths of follow-up. Moreover, Kaplan-Meier curves present a frequently used general graphic approach to display time-to-event outcomes. A solid understanding of how Kaplan-Meier curves are generated and how they should be analyzed and interpreted is of great importance to appraise urological literature in daily clinical practice. This article describes the basic principles of Kaplan-Meier analysis, possible variants and pitfalls. Improved knowledge of Kaplan-Meier analysis can help to improve Evidence-based urology and its application in patient care.
