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Recommendations for reporting randomized controlled trials of herbal interventions: explanation and elaboration

  • Joel J. Gagnier
    Correspondence
    Corresponding author. 5955 Ontario Street, Unit #307, Windsor, Ontario, Canada, N8S1W6. Tel.: +1-519-974-9690; fax: +1-519-258-2396.
    Affiliations
    Department of Health Policy, Management and Evaluation, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada

    Canadian College of Naturopathic Medicine, Toronto, Ontario, Canada
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  • Heather Boon
    Affiliations
    Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada
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  • Paula Rochon
    Affiliations
    Department of Health Policy, Management and Evaluation, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada

    Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada
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  • David Moher
    Affiliations
    Children's Hospital of Eastern Ontario Research Institute, Ottawa, Canada

    Department of Pediatrics, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada

    Department of Epidemiology & Community Medicine, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
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  • Joanne Barnes
    Affiliations
    Centre for Pharmacognosy & Phytotherapy, School of Pharmacy, University of London, London, United Kingdom
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  • Claire Bombardier
    Affiliations
    Department of Health Policy, Management and Evaluation, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada

    Institute for Work & Health, Toronto, Ontario, Canada
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  • for the CONSORT Group
    Author Footnotes
    1 Members of this group are listed in Section 8.
  • Author Footnotes
    1 Members of this group are listed in Section 8.

      Abstract

      Controlled trials that use randomized allocation are the best tool to control for bias and confounding in trials testing clinical interventions. Investigators must be sure to include information that is required by the reader to judge the validity and implications of the findings in the reports of these trials. In part, complete reporting of trials will allow clinicians to modify their clinical practice to reflect current evidence toward the improvement of clinical outcomes. The consolidated standards of reporting trials (CONSORT) statement was developed to assist investigators, authors, reviewers, and editors on the necessary information to be included in reports of controlled clinical trials. The CONSORT statement is applicable to any intervention, including herbal medicinal products. Controlled trials of herbal interventions do not adequately report the information suggested in CONSORT. Recently, reporting recommendations were developed in which several CONSORT items were elaborated to become relevant and complete for randomized controlled trials of herbal medicines. We expect that these recommendations will lead to more complete and accurate reporting of herbal trials. We wrote this explanatory document to outline the rationale for each recommendation and to assist authors in using them by providing the CONSORT items and the associated elaboration, together with examples of good reporting and empirical evidence, where available, for each. These recommendations for the reporting of herbal medicinal products presented here are open to revision as more evidence accumulates and critical comments are collected.

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