Well informed uncertainties about the effects of treatments

How should clinicians and patients respond?

Uncertainties about the effects of treatments are inevitable. Whatever the basis for judgments about the likely effects of treatments in individual patients, there is no escape from the reality that every such judgment initiates a clinical trial in which there can be no certainty that an individual patient will benefit. Sometimes the judgment will draw on the patient's past experience of the treatment, more usually on the clinician's experience of treating other patients. Increasingly, clinicians and patients are taking account of collective experience—the results of formal evaluations of treatments.1 Maybe this is because they recognise that treatments can sometimes do more harm than good, sometimes on a devastating scale.

What should happen if, after weighing the best available evidence from collective experience and taking account of patients' preferences, residual uncertainty remains about which treatment options should be chosen? Should the clinician and patient simply press ahead with yet another poorly controlled clinical trial? It is surprising that such questions seem to have been addressed relatively rarely. One attempt to do so was published in this journal three years ago by a medical ethicist. “If we are uncertain about the relative intrinsic merits of [different] treatments,” he wrote, “then …