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Empirical evidence against placebo controls
1University of Alabama at Birmingham School of Medicine, Birmingham, Alabama, USA.
Journal of Medical Ethics
|August 11, 2017
Summary
Clinical researchers infrequently use placebo-controlled trials when effective therapies exist, suggesting ethical concerns outweigh methodological justifications. This practice challenges the Declaration of Helsinki
Area of Science:
- Medical Ethics
- Clinical Research Methodology
- Evidence-Based Medicine
Background:
- The Declaration of Helsinki permits placebo-controlled trials (PCTs) even with established therapies if methodologically justified.
- This allowance raises ethical concerns regarding beneficence, as it may involve withholding known effective treatments.
- A hypothesis was formed that researchers avoid PCTs when established therapies exist due to ethical considerations.
Purpose of the Study:
- To investigate the actual use of PCTs in clinical practice when established therapies are available.
- To explore the discrepancy between ethical guidelines and researcher behavior regarding PCTs.
- To provide evidence for potential reconsideration of the Declaration of Helsinki.
Main Methods:
- A systematic search was conducted for PCTs published in 2015.
- The search focused on the five highest-impact general medical journals.
- Identified PCTs were analyzed to determine if established effective therapies existed for the studied indications.
Main Results:
- A total of 70 PCTs were identified.
- 66 of these PCTs were for conditions lacking established effective therapies.
- Only four PCTs utilized placebo controls despite the availability of effective treatments.
Conclusions:
- The infrequent use of PCTs with established therapies indicates a gap between the Declaration of Helsinki and ethical acceptability in practice.
- Clinical researchers appear hesitant to employ PCTs when effective treatments are available, prioritizing patient beneficence.
- The findings suggest a need to re-evaluate and potentially revise the Declaration of Helsinki based on current clinical research practices.
Keywords:
placebo
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