title: Matched-pair study showed higher quality of placebo-controlled trials in Western phytotherapy than conventional medicine.
abstract: OBJECTIVE
  Herbal medicine (phytotherapy) is widely used, but the evidence for its effectiveness is a matter of ongoing debate. We compared the quality and results of trials of Western phytotherapy and conventional medicine.
  
  
  METHODS
  A random sample of placebo-controlled trials of Western phytotherapy was identified in a comprehensive literature search (19 electronic databases). Conventional medicine trials matched for condition and type of outcome were selected from the Cochrane Central Controlled Trials Register (issue 1, 2003). Data were extracted in duplicate. Trials described as double-blind, with adequate generation of allocation sequence and adequate concealment of allocation were assumed to be of higher methodological quality.
  
  
  RESULTS
  Eighty-nine herbal medicine and 89 matched conventional medicine trials were analyzed. Studies of Western herbalism were smaller, less likely to be published in English, and less likely to be indexed in MEDLINE than their counterparts from conventional medicine. Nineteen (21%) herbal and four (5%) conventional medicine trials were of higher quality. In both groups, smaller trials showed more beneficial treatment effects than larger trials.
  
  
  CONCLUSIONS
  Our findings challenge the widely held belief that the quality of the evidence on the effectiveness of herbal medicine is generally inferior to the evidence available for conventional medicine.
authors.affiliation: Department of Social and Preventive Medicine, University of Bern, Berne, Switzerland.
authors.forename: Linda
authors.initials: L
authors.lastname: Nartey
authors.forename: Karin
authors.initials: K
authors.lastname: Huwiler-Müntener
authors.forename: Aijing
authors.initials: A
authors.lastname: Shang
authors.forename: Katharina
authors.initials: K
authors.lastname: Liewald
authors.forename: Peter
authors.initials: P
authors.lastname: Jüni
authors.forename: Matthias
authors.initials: M
authors.lastname: Egger
mesh_terms: D015510:Clinical Medicine / Q000592:standards*; D018849:Controlled Clinical Trials as Topic / Q000592:standards*; D006801:Humans; D016555:Matched-Pair Analysis; D008517:Phytotherapy / Q000592:standards*; D011643:Publishing; D036301:Qualitative Research; D012107:Research Design / Q000592:standards; D016896:Treatment Outcome