The principle of parity: the 'placebo effect' and physician communication.

The use of 'placebos' in clinical practice is a source of continued controversy for physicians and medical ethicists. There is rarely any extensive discussion on what 'placebos' are and how they work. In this paper, drawing on Louhiala and Puustinen's work, the author proposes that the term 'placebo effect' be replaced in clinical contexts with the term 'positive care effect'. Medical treatment always takes place in a 'context of care' that encompasses all the phenomena associated with medical intervention it includes the particular method of treatment, the interpersonal relationships between medical staff and the patient and other factors, including physicians' and patients' beliefs in the power of the treatment. Together, these phenomena can result in a full spectrum of therapeutic effects to the patient--from no effects, to small effects, to large effects. In cases where there are significant therapeutic benefits to the patient, 'positive care effects' may be spoken of. Since the ethical codes of the General Medical Council and the American Medical Association demand transparency with respect to patient treatment and insist on complete openness in 'placebo' usage, the author argues that, as a matter of conceptual rigour and consistency, if the term 'placebo effect' is replaced by 'positive care effect', these ethical codes appear to insist on transparency about all such beneficial components of treatment. Given that this appears to be a counterintuitive obligation, the author concludes the paper with some comments on the clinical consequences of this conceptual revision, including a brief discussion of how this important debate might develop.