Abstract
The determination of the appropriate sample size is an important aspect of planning a clinical trial. In recent years, procedures for estimation of a nuisance parameter to adjust the sample size if necessary have been examined. Here, it is assumed that the clinical trial is conducted for the comparison of two treatments, where the observations are assumed to have normal distributions with a common unknown variance. For sample size determination, the variance is assumed known and the resulting sample size is sensitive to misspecification of the variance. An estimate of the variance, obtained while the clinical trial is ongoing, can often be used to assess the appropriateness of the assumed variance. The use of a blinded estimate of the variance to potentially adjust the sample size is examined.
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Based upon a poster presentation at the DIA Annual Meeting, June 2000, San Diego, California.
This research was conducted while the first author was employed at Pfizer Global Research and Development, Ann Arbor MI.
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Bristol, D.R., Shurzinske, L. Blinded Sample Size Adjustment. Ther Innov Regul Sci 35, 1123–1130 (2001). https://doi.org/10.1177/009286150103500409
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DOI: https://doi.org/10.1177/009286150103500409