Literature DB >> 12468480

Informing participants of allocation to placebo at trial closure: postal survey.

Zelda Di Blasi1, Ted J Kaptchuk, John Weinman, Jos Kleijnen.   

Abstract

OBJECTIVES: To assess whether and how investigators of placebo controlled randomised trials inform participants of their treatment allocation at trial closure and to assess barriers to feedback.
DESIGN: Postal survey with a semistructured questionnaire. PARTICIPANTS: All investigators who published a placebo controlled randomised trial in 2000 in five leading medical journals, and a random sample of 120 trials listed in the national research register database. MAIN OUTCOME MEASURES: Number of investigators who informed participants of their treatment allocation at trial closure, methods for delivering the information, and barriers to unmasking treatment.
RESULTS: 45% of investigators informed either all or most participants of their treatment allocation, and 55% did not inform any participant or only informed those who asked. The main reasons for not informing participants were that the investigators never considered this option (40%) or to avoid biasing results at study follow up (24%).
CONCLUSION: Further research is required to examine sensitive ways to communicate treatment information to trial participants.

Entities:  

Keywords:  Biomedical and Behavioral Research; Empirical Approach

Mesh:

Substances:

Year:  2002        PMID: 12468480      PMCID: PMC137805          DOI: 10.1136/bmj.325.7376.1329

Source DB:  PubMed          Journal:  BMJ        ISSN: 0959-8138


  14 in total

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3.  Consumers are helping to prioritise research.

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Review 4.  Is the placebo powerless? An analysis of clinical trials comparing placebo with no treatment.

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5.  Involving consumers in designing, conducting, and interpreting randomised controlled trials: questionnaire survey.

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Journal:  Stat Med       Date:  1982 Oct-Dec       Impact factor: 2.373

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9.  Influence of context effects on health outcomes: a systematic review.

Authors:  Z Di Blasi; E Harkness; E Ernst; A Georgiou; J Kleijnen
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10.  Placebo-controlled trials and active-control trials in the evaluation of new treatments. Part 1: ethical and scientific issues.

Authors:  R Temple; S S Ellenberg
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  17 in total

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6.  Participants' experiences of being debriefed to placebo allocation in a clinical trial.

Authors:  Felicity L Bishop; Eric E Jacobson; Jessica Shaw; Ted J Kaptchuk
Journal:  Qual Health Res       Date:  2012-06-06

7.  Feedback of trial results to participants: a survey of clinicians' and patients' attitudes and experiences.

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8.  Reactions to treatment debriefing among the participants of a placebo controlled trial.

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9.  Unblinding in Randomized Controlled Trials: A Research Ethics Case.

Authors:  Ayesha Bhatia; Paul S Appelbaum; Katherine L Wisner
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Review 10.  Providing trial results to participants in phase III pragmatic effectiveness RCTs: a scoping review.

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