Focus on Alternative and Complementary Therapies
www.pharmpress.com/fact
Focus Alternat Complement Ther©2005 Pharmaceutical Press
Focus Altern Complement Ther 2003; 8: 279–80
Reviewed by K Schmidt, Exeter, UK
Researchers from different scientific backgrounds have been trying for decades to crack the nut of the so-called ‘placebo effect’. In a workshop organised in November 2000 by the National Institutes of Health and the National Center for Complementary and Alternative Medicine in Bethesda, Maryland, USA, and involving staff of the National Institute of Diabetes, Digestive and Kidney Diseases, the basis for and potential applications of the ‘placebo effect’ were explored. Researchers from a wide range of disciplines examined the definition and history of the field, social and cultural aspects of the placebo effect, biological and ethical aspects and issues related to the use of placebo in clinical trials. This book summarises the results of this workshop. The main goal of the book is to develop recommendations for future research to further elucidate, to account for and to develop clinical applications of the placebo effect. The issues discussed are ‘more-than-ever’ topical and as relevant to CAM as to conventional medicine.
In the introductory chapter the delegates of the conference express their experiences with the placebo and its effect and point out that many of these experiences differ from what Hrobjartsson and Gotzsche found in their analysis.1 The main fallacies regarding the interpretation of the placebo being discussed are, for example, that a placebo is often mistaken for a sham and that some researchers still see the placebo effect as ‘noise’ in a randomised controlled trial. Moerman brings forward his idea of the ‘meaning response’: in a patient–practitioner interaction the meaning response consists of language, procedures, settings and the processing of information.
Various explanations for the psychosocial mechanism of the placebo effect have previously been suggested, such as personality factors, therapeutic relationship, expectations, hope and classical conditioning. However, scientists all over the world still argue whether it is more important to test the efficacy of the placebo effect or its mechanism of action. In the next chapter, a historical perspective is being taken to lead the reader through the changes in attitudes and perceptions of the placebo effect over the last decades. It is observed that not everyone sees the placebo effect as (in theory) functioning as a therapy.
Chapter 3 discusses ethical issues of the placebo effect and weighs the benefits for individual patients from placebo use against possible risks for patients, health professionals and society as a whole. In Chapter 4 the meaning response as consisting of physiological and/or psychological effects of meaning in the treatment of illnesses is discussed in more detail and Chapter 5 seeks explanations for mechanisms, such as cognition, personality and social learning.
Regression to the mean is explained in Chapter 7 and it is suggested that it likely explains much of what has been described as the placebo effect but that it cannot explain all of the reported placebo effects. Further to previous discussions, in Chapters 8 and 9 it is argued that the placebo effect represents a phenomenon linking belief to well-being that can be analysed systematically to prove insights into how beliefs might affect immune responses and disease expression or severity.
The second part of the book – Chapters 10–14 – provide a discussion of the use of placebos in clinical trials and the pros and cons of equivalence trials. Finally, in Chapter 15 priorities for future research and different research ideas that need to be further developed by healthcare professionals are discussed.
To summarise the content of the book, some of the aspects of the placebo and the placebo effect are admittedly being repeated throughout the chapters. However, the book gives the reader a valuable insight into the process of developing ideas about the phenomena collected by researchers with various medical backgrounds.
