Why clinical trials?

The question "Why clinical trials in surgery?" (or "Why not more clinical trials in surgery?") appears to have an answer so simple as to make one hesitate to mention it: the well-designed and well-executed clinical trial is a sieve for innovations in treatment. We must always be prepared to accept occasional mistakes and we must remember, "to err is human." Depending on the characteristics of the design, there is a larger or smaller chance of not identifying an improvement in treatment or of mistakenly identifying a treatment as an improvement. In contrast to "expert judgement," in a proper clinical trial the probability or frequency of committing such errors can be evaluated and, within budget limitations, can be controlled by the investigator(s). The clinical trial removes the need for authority or expert opinion and replaces such expertise with a method. This method has been tested by experience, and it undergoes continual reexamination and improvement. Furthermore, when the expert--however excellent--is gone, so is the expertise; with a method we have a tool that is not ephemeral, but is permanently available.