Number Unnecessarily Treated in Relation to Harm: A Concept Physicians and Patients Need to Understand.

Physicians are legally and ethically compelled to present their patients with available evidence on the potentially beneficial and harmful effects of a proposed medical or surgical treatment. This, however, is only half the story. It does not offer the patient a clear view of the pros and cons of one treatment option versus another, or even versus no treatment at all. Explicitly stating the number of patients who will not benefit from the proposed treatment, in combination with the risk of a complication, may better inform patients and help them determine and express their treatment preference. This may also help standardize the informed consent procedure.