BACKGROUND Central to the design of a randomised controlled trial is the calculation of the number of participants needed. This is typically achieved by specifying a target difference and calculating the corresponding sample size, which provides reassurance that the trial will have the required statistical power (at the planned statistical significance level) to identify whether a difference of...

Kanji Hioka Graduate School of Science and Engineering, Yamaguchi University 1677-1 Yoshida, Yamaguchi 753-8512, Japan [email protected] Yoshimasa Miwa Graduate School of Science and Engineering, Yamaguchi University 1677-1 Yoshida, Yamaguchi 753-8512, Japan [email protected] Chen Li Human Genome Center, University of Tokyo 4-6-1 Shirokanedai, Minatoku, Tokyo 108-8639, Ja...

A sample size calculation for logistic regression involves complicated formulae. This paper suggests use of sample size formulae for comparing means or for comparing proportions in order to calculate the required sample size for a simple logistic regression model. One can then adjust the required sample size for a multiple logistic regression model by a variance inflation factor. This method re...

Exact power and sample size calculation for bioequivalence studies with high order crossover designs using statistical software nQuery are presented. Such calculation can be very easily performed, and thus provides a convenient tool for practical usage.

In clinical research, parameters required for sample size calculation are usually unknown. A typical approach is to use estimates from some pilot studies as the true parameters in the calculation. This approach, however, does not take into consideration sampling error. Thus, the resulting sample size could be misleading if the sampling error is substantial. As an alternative, we suggest a Bayes...

background and purpose: sample size and its determination is one of the most important problems in health researches. calculating sample size for prevalence studies is one of the common questions of sample size topics. minimum sample size with least complexity is desirable in order to achieve the basic goal of these studies. this study aims to compare two formulas of sample size calculation for...

We present a concise review of the recent theoretical progress concerning the standard model calculation of the inclusive radiative B̄ → Xsγ decay. Particular attention is thereby devoted to the calculations of the next-to-next-to-leading order fixed-order O(αs) contributions, non-local O(αsΛ/mb) power corrections, and logarithmic-enhanced O(αs) cut-effects to the decay rate. The current status ...

The equations of motion for a massive spin2 Rarita-Schwinger field in a finite-range, central, Lorentz scalar potential are developed. It is shown that the resulting density may not be everywhere positive definite.