A NOTE ON SAMPLE SIZE CALCULATION FOR MEAN COMPARISONS BASED ON NONCENTRAL t-STATISTICS
- 12 January 2002
- journal article
- Published by Taylor & Francis in Journal of Biopharmaceutical Statistics
- Vol. 12 (4) , 441-456
- https://doi.org/10.1081/bip-120016229
Abstract
One-sample and two-sample t-tests are commonly used in analyzing data from clinical trials in comparing mean responses from two drug products. During the planning stage of a clinical study, a crucial step is the sample size calculation, i.e., the determination of the number of subjects (patients) needed to achieve a desired power (e.g., 80%) for detecting a clinically meaningful difference in the mean drug responses. Based on noncentral t-distributions, we derive some sample size calculation formulas for testing equality, testing therapeutic noninferiority/superiority, and testing therapeutic equivalence, under the popular one-sample design, two-sample parallel design, and two-sample crossover design. Useful tables are constructed and some examples are given for illustration.Keywords
This publication has 2 references indexed in Scilit:
- On Sample Size Calculation in Bioequivalence TrialsJournal of Pharmacokinetics and Pharmacodynamics, 2001
- A Note on Sample Size Determination for Bioequivalence Studies with Higher-Order Crossover DesignsJournal of Pharmacokinetics and Biopharmaceutics, 1997