Abstract
When reported in publications, sample size calculations and statistical methods were often explicitly discrepant with the protocol or not pre-specified. Such amendments were rarely acknowledged in the trial publication. The reliability of trial reports cannot be assessed without having access to the full protocols.
Keywords
Sample size determinationProtocol (science)InterimClinical trialSample (material)MedicineMissing dataResearch designStatisticsOutcome (game theory)Medical physicsSubgroup analysisData collectionComputer scienceData miningConfidence intervalAlternative medicineInternal medicineMathematicsPathologyGeography
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Publication Info
- Year
- 2008
- Type
- article
- Volume
- 337
- Issue
- dec04 1
- Pages
- a2299-a2299
- Citations
- 195
- Access
- Closed
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Cite This
A.-W. Chan,
A. Hrobjartsson,
Karsten Juhl Jørgensen
et al.
(2008).
Discrepancies in sample size calculations and data analyses reported in randomised trials: comparison of publications with protocols.
BMJ
, 337
(dec04 1)
, a2299-a2299.
https://doi.org/10.1136/bmj.a2299
Identifiers
- DOI
- 10.1136/bmj.a2299