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Published on: January 22, 2013
Control of false positives in randomized phase III clinical trials
Changyu Shen1, Ziyue Liu1, Huiping Xu1
1a Department of Biostatistics, School of Medicine, Richard M. Fairbanks School of Public Health , Indiana University , Indianapolis , IN , USA.
This study estimates the proportion of null or negative efficacy (PNN) in U.S. Phase III clinical trials. The findings suggest a low PNN, indicating a small number of false positive results from these critical medical intervention evaluations.
Area of Science:
- Biostatistics
- Clinical Trials
- Pharmaceutical Research
Background:
- Randomized Phase III clinical trials are the gold standard for evaluating medical interventions.
- The number of false positives generated by numerous industry-sponsored Phase III trials in the U.S. is not well understood.
- Estimating the proportion of null or negative efficacy (PNN) is crucial for controlling false positives.
Purpose of the Study:
- To estimate the proportion of null or negative efficacy (PNN) in U.S. Phase III clinical trials.
- To assess the potential number of false positive findings in this trial population.
Main Methods:
- A novel Bayesian deconvolution method was employed to estimate PNN.
- Data from clinicaltrials.gov and other sources were used, focusing on trials completed between 2008-2012.
- 1393 trials meeting study criteria were identified, with results analyzed for 1221 trials.
Main Results:
- Among 1221 analyzed trials, 64.6% showed statistically significant intervention superiority.
- 45.9% of these significant trials had a two-sided p-value < 0.001.
- The estimated PNN was found to be no more than 7-9%.
Conclusions:
- The study estimates that 18-22% of trials may have at least one null or negative efficacy comparison.
- This suggests an expectation of no more than 6-8 trials with false positives over a 5-year period.
- The findings contribute to understanding the reliability of Phase III clinical trial outcomes.
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