Each project has a frame. Time, Money, Objectives, Risks, Chances are tailored to the needs of our costomer.
The most important question: How many subjects do we need, how great is the study?
To produce reliable data (have sufficient study power) - the required number of participants (observations, cases) can be calculated from preliminary data. This saves time and money. Either data are available before start, or we realize a pilot phase and perform an interim analysis.
Each project plan should be optimized by "statistical sample size".
We calculate the required sample sizes,
either with previous data from a pilot project or based on an estimate !