Pilot Power

Assumed Parameters

in standard deviation units

Design Choices

Simulation Settings

Initial simulation runs with default settings. Click above to update simulation with new parameters.

Please be patient: Calculations take some time and sometimes have dependencies leading to multiple steps being completed at once.

PilotPower on GitHub
Pilot Power simulates the use of pilot studies in planning randomized controlled trials under different user-specified conditions.
Based upon our simulated data, the below table lists how often across simulations we would proceed to a full trial when applying the below decision rules to our simulated pilot study results.

We now do a power analysis to determine the sample size required to detect effects of a certain size in a full trial. This is done in two ways: once using the pre-determined practically significant effect size, and once using the effect size observed in the simulated pilot study. The table below shows, across all simulations, the average sample size needed to detect effects in a full trial.


We now make conclusions about the effectiveness of the intervention based upon our full trial.

CSV File

The below data are from simulations where all sizes are made to be large enough to detect the observed pilot study effect size.

CSV File

The below data are from simulations where all sample sizes are large enough to detect the practically significant effect size.