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Psychother Psychosom Med Psychol 2002; 52(8): 332-342
DOI: 10.1055/s-2002-33077
Originalarbeit
© Georg Thieme Verlag Stuttgart · New York

Plazebo und Plazeboeffekte - Eine Bestandsaufnahme

Placebo and Placebo Effects - A ReviewHarald  Walach1 , Catarina  Sadaghiani1
  • 1Universitätsklinikum Freiburg, Institut für Umweltmedizin und Krankenhaushygiene
Further Information

Publication History

Eingegangen: 14. November 2000

Angenommen: 8. Februar 2002

Publication Date:
31 July 2002 (online)

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Zusammenfassung

Plazebogruppen in klinischen Studien dienen dazu, eine Reihe „unspezifischer” Effekte zu kontrollieren, um diesen die spezifischen Effekte der untersuchten Medikation gegenüberzustellen. Die Betonung spezifischer Effekte in der klinischen Forschung ist verständlich, geht es ihr um die Entdeckung neuer und wirksamer Arzneien. Diese Beschränkung in der klinischen Forschung vermittelte jedoch den Eindruck, die unspezifischen oder Plazeboeffekte seien therapeutisch wenig relevant. Im Folgenden wird der Plazebobegriff neu beleuchtet und es werden einige empirische Befunde dargestellt, die die Bedeutung von Plazeboeffekten unterstreichen. Die Befunde legen nahe, dass ein wertvoller therapeutischer Bestandteil jeglicher Intervention der Effekt ist, der auf die subjektive Bedeutung zurückgeht, die die Intervention für einen Patienten hat. Es werden einige Beispiele besprochen, wie solche unspezifischen Effekte therapeutisch maximiert werden können und welche Konsequenzen diese Betrachtungsweise für die Evaluation therapeutischer Maßnahmen hat.

Abstract

Placebo controls in clinical trials are usually employed to filter out undesired, psychological or non-specific effects from „true” therapeutic effects. Although this is useful in the context of clinical trials for the purpose of proving pharmacological efficacy, it is misleading to generalize this strategy to therapy as a whole. This would imply that placebo effects are irrelevant. Precisely this opinion is criticized in this paper. After some consideration about an appropriate notion of placebo, some empirical evidence is reviewed which underlines the importance of placebo effects. It is likely that the unspecific effects due to the individual meaning of an intervention are an important factor of any therapeutic approach. It would be therapeutically desirable to maximize these factors. This point of view would also have consequences on how interventions have to be evaluated.

Key words

Placebo - Placebo effect - Non-specific effects - Meaning

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PD Dr. Dr. phil. Harald Walach

Universitätsklinikum Freiburg · Institut für Umweltmedizin und Krankenhaushygiene

Hugstetterstraße 55

79106 Freiburg

Email: walach@ukl.uni-freiburg.de

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