Is the placebo effect a fact or a myth


The placebo effect - a critical evaluation

The so-called placebo effect has been a scientific fact for 50 years since Henry K. Beecher published his groundbreaking article "The Powerful Placebo" in 1955. Since then it has been considered a kind of natural constant that the desired therapeutic success can be brought about in a third of all patients simply by the suggestive administration of a sugar pill. In recent times, the assumed extent has grown even further: the placebo effectiveness is estimated at an average of 70% for almost all diseases. These claims have been popularized in all major medical journals, but have never been critically challenged.
Placebos are important in medicine today in three ways:
  1. Since - as suspected - any drug effect, including an undesired one, can be imitated by the administration of placebos, mandatory blinding is required in all drug studies. In placebo-controlled studies, the true drug effect results from subtracting the placebo effect from the drug effect.
  2. Because of the supposedly high rate of therapeutic placebo successes and the conceivable cost savings at the same time, it is discussed to use placebos more therapeutically.
  3. Therapy successes whose specific mode of action cannot be explained with common concepts (e.g. complementary medicine, psychotherapies from different schools) are often declared as placebo effects.
The mere suggestion of the therapy, the deliberate deception of the patient - the "healing lie" - is in diametrical contrast to the concept of empowerment, the decision-making autonomy and self-determination or co-determination of the patient. Therefore, before the principle of deception is integrated into therapy, a critical review is necessary.
800 placebo papers were analyzed to determine whether, as claimed, a therapeutic effect of the placebo administration was convincingly demonstrated. The result was surprising. Contrary to popular claims, none of the studies analyzed contained a convincing demonstration of a therapeutic placebo effect. Rather, there are a number of different factors that can simulate placebo effects: Spontaneous course of the disease, spontaneous fluctuations in symptoms, regression to the mean, accompanying therapeutic measures, courtesy information, experimental subordination, serious methodological deficiencies in the studies, irrelevant test criteria, incorrect citation, etc.1,2,3 Overall, the widespread literature on the size and frequency of the placebo effect are unfounded and largely exaggerated, if not entirely wrong.
These results were compared with one of the Nordic Cochrane group im New England Journal of Medicine published meta-analysis4 verified and confirmed: 114 randomized studies with placebo groups and untreated groups did not show any superiority of placebo treatment compared to zero treatment, except possibly for pain treatment, which may also be study artifacts.

literature
  1. Kienle GS, Kiene H. The Powerful Placebo Effect. Fact or fiction? Journal of Clinical Epidemiology 1997; 50 (12): 1311-1318.
  2. Kienle GS. The so-called placebo effect - illusion, facts, reality. Stuttgart: Schattauer Verlag; 1995, 95 pp.
  3. Kienle GS, Kiene H. Placebo effect and placebo concept. A critical methodological and conceptual analysis of data on the extent of the placebo effect. Researching complementary medicine 1996; 3 (3): 121-138.
  4. Hróbjartsson A, Gøtzsche P. Is the placebo powerless? An analysis of clinical trials comparing placebo with no treatment. The New England Journal of Medicine 2001; 344 (21): 1594-1602.
Further publications on the topic
  1. Kienle GS. The placebo effect - a myth between self-healing and self-deception. In: Perl F, Beckerman M (Eds). Gynecology and Obstetrics. Basel: Schwabe Verlag Basel; 2004. pp. 131-141.
  2. Kienle G, Kiene H. A critical reanalysis of the concept, magnitude and existence of placebo effects. In: Peters D (Ed), Understanding the Placebo Effect in Complementary Medicine. Theory, Practice and Research. Edinburgh: Churchill Livingstone; 2001. pp. 31-51.
  3. Kienle GS. The placebo effect - a critical evaluation. Documentation volume of the 18th university course in health economics, 5.-7. October 1998, Bildungshaus Kloster Neustift near Brixen / South Tyrol. Institute for Public Finance at the University of Innsbruck. Austrian Society for Health Economics; 1999, pp. 1-17.
  4. Kiene H, Kienle GS. The placebo effect: a scientific critique. Complementary Therapies in Medicine 1998; 6: 14-24.
  5. Kienle GS, Kiene H. Placebo effect and placebo concept. A critical methodological and conceptual analysis of data on the extent of the placebo effect. The gynecologist 1998; 39 (4): 571-585.
  6. Kienle GS. The placebo effect - a critical evaluation. Deutsche Apotheker Zeitung 1998; 138 (30): 33-41.
  7. Kienle GS, Kiene H. The Placebo Effect - A Persistent Rumor (II). Raum & Zeit 1998; 91: 67-72.
  8. Kiene H, Kienle GS. Placebo effect and religion. Research Complementary Medicine 1997; 5: 296.
  9. Kienle GS. Methodological criticism of the so-called placebo effect. In: Baur MP, Fimmers R, Blettner M (eds). Health informatics, biometrics and epidemiology GMDS '96. 41st Annual Meeting of GMDS, Bonn, September 1996. Munich: MMV; 1997. pp. 365-369.
  10. Kienle GS. Critical analysis of the scientific basis of the so-called placebo effect. Significance of the placebo argument for empirical medicine. Empirical Medicine 1997; 5: 298-307.
  11. Kienle GS, Kiene H. Placebo effect and placebo concept. A critical methodological and conceptual analysis of data on the extent of the placebo effect. The Rod of Mercury 1997; 50 (3): 137-156.
  12. Kienle GS. Methodological criticism of the so-called placebo effect. Circular letter for the staff of the Medical Section at the Goetheanum around the world 1997; 22: 81-85.
  13. Kienle GS, Kiene H. The Placebo Effect - A Persistent Rumor (I). Raum & Zeit 1997; 90: 63-70.
  14. Kienle GS. The Placebo Effect - Reality or Illusion ?. In: Hornung J (ed.). Research methods in complementary medicine. About the need for a methodological renewal. Stuttgart: Schattauer Verlag; 1996. pp. 204-213.
  15. Kienle GS, Kiene H. Placebo Effect and Placebo Concept: A Critical Methodological and Conceptual Analysis of Reports on the Magnitude of the Placebo Effect. Alternative Therapies in Health and Medicine 1996; 2 (6): 39-54.