Impact of Clinician Beliefs on Sample Size Calculation in Clinical Trials
Author Information
Author(s): Fayers P M, Cuschieri A, Fielding J, Craven J, Uscinska B, Freedman L S
Primary Institution: Cancer Division, MRC Clinical Trials Unit
Hypothesis
How do clinician beliefs affect sample size calculations in clinical trials?
Conclusion
The study highlights that relying solely on the beliefs of a small group of enthusiastic clinicians can lead to significant miscalculations in sample size requirements for clinical trials.
Supporting Evidence
- The initial survey suggested a survival improvement of 9.4%.
- The second survey indicated a more realistic difference of 9.5%.
- Revised calculations suggested that between 800 and 1200 patients would have been required based on updated opinions.
Takeaway
Doctors' opinions about how well a treatment works can change how many patients are needed in a study, and if too few doctors are asked, it can lead to mistakes.
Methodology
The study involved surveys of surgeons' opinions on expected survival rates before and after a clinical trial.
Potential Biases
There is a risk of bias if sample size calculations are based on the opinions of a small group of enthusiastic clinicians rather than a broader expert consensus.
Limitations
The study's findings may not apply to all clinical trials, as it focused on a specific trial and a limited group of surgeons.
Participant Demographics
Surgeons experienced in treating gastric carcinoma.
Digital Object Identifier (DOI)
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