Useful R packages

This task view gathers information on specific R packages for design, monitoring and analysis of data from clinical trials. It focuses on including packages for clinical trial design and monitoring in general plus data analysis packages for a specific type of design. Also, it gives a brief introduction to important packages for analyzing clinical trial data. Please refer to task views ExperimentalDesign, Survival, Pharmacokinetics, Meta-analysis for more details on these topics.

precisely is a study planning tool to calculate sample size based on precision rather than power. Power calculations are focused on whether or not an estimate will be statistically significant; calculations of precision are based on the same principles as power calculation but turn the focus to the width of the confidence interval.

The basic idea of calculating power or sample size with functions in the pwr package is to leave out the argument that you want to calculate. If you want to calculate power, then leave the power argument out of the function. If you want to calculate sample size, leave n out of the function. Whatever parameter you want to calculate is determined from the others.