A special issue of Philosophical Transactions of the Royal Society B, a publication of the UK’s national academy of science, recently examined the science and theory behind the placebo effect in addition to its future role in health care.
The placebo effect is a beneficial health outcome resulting from a person’s anticipation that an intervention—pill, procedure, or injection, for example—will help them. A clinician’s style in interacting with patients also may bring about a positive response that is independent of any specific treatment.
Themes discussed in the issue included:
- Previous research has found that empathy and social learning, emotion and motivation, and spirituality and the healing ritual may be important factors for understanding the placebo effect. Information about these factors as well as other well-studied placebo mechanisms will help to build further research about the biology of placebo and how the body uses it to heal itself.
- A focus on translational (“bench-to-bedside”) research, particularly for placebo studies, is to develop strategies for using placebo response interventions in clinical settings. Because much of placebo research has been done on humans, there is potential for using some of this scientific evidence in the field of patient care. Although recommending and prescribing placebo treatments remains controversial, the researchers explore the current scientific literature to better understand how, when, and why placebo treatments might be used in health care.
- Conditioning and expectancy are two of the most accepted theories in placebo response research. For example, a doctor’s visit in which both the process of being treated (conditioning) as well as the physician’s verbal suggestions that a treatment may be beneficial (expectancy) may promote a placebo response. The researchers suggest that by examining placebo research from the perspective of these different learning and verbal mechanisms, studies can be designed to investigate the effect of the placebo response on medical care.
Based on the evaluation of placebo research found in this issue, the researchers concluded that more rigorously designed studies are needed in order to better understand the complexities of the placebo effect and how it can be adapted for a clinical setting.
Meissner K, Kohls N, Colloca L. Introduction to placebo effects in medicine: mechanisms and clinical implications. Philosophical Transactions of the Royal Society B.;366:1783–1789.2011
Colloca L, Miller FG. How placebo responses are formed: a learning perspective. Philosophical Transactions of the Royal Society B.;366:1859–1869.2011
Colloca L, Miller FG. Harnessing the placebo effect: the need for translational research. Philosophical Transactions of the Royal Society B.;366:1922–1930.2011