Prostatectomy or Watchful Waiting in Prostate Cancer

Abstract
In their article comparing prostatectomy with watchful waiting, Holmberg et al. (Sept. 12 issue)1 present their analysis according to the intention-to-treat principle, but the true treatment effect might be larger than that observed because of noncompliance with the protocol.2 Presentation of information on the outcome in the participants who did not comply with the protocol and an additional per-protocol analysis could give more insight into the real treatment effect.