At the coalface--medical ethics in practice. First, do no harm

When a physician acts as both doctor and researcher conflicts can develop. When a doctor does not know whether a patient is taking active drug or placebo, any new medical problems can result in a dilemma. Is the patient's suffering a side effect of the medication or is this a new medical problem? Mrs W's case demonstrates the problem that can occur when the physician is blinded in the name of research.