With respect to power, for the parameter values assumed here, a sample size of around 300 case/mother duos seemed to be required to give reasonable power for detection of effects.
A randomised control trial may take at least four years for a single surgeon to recruit enough patients for a trial of reasonable power to compare two different dressings (estimated 140 patients in each group).
Although using all the data generated by the exon pilot project has reasonable power to detect association of low frequency variants under the dominant, additive and multiplicative models with typical genotype relative risks, the power of the potential Pilot 14 M array to detect association of low frequency variants is low.
They also suggest adequate control of Type I error and reasonable power to detect direct effects of sufficient magnitude.
Specifically, based on a simulation study, our investigation had limited power to detect a relative effect modification of 2 but reasonable power to detect a relative effect modification of 3.
This procedure has reasonable power for a wide range of pregnancy subsets that might be at increased risk of miscarriage, albeit with less power than the standard test with the subset at increased risk specified correctly (see supplemental tables 1a-1e in appendix 6 on bmj.com).
In case that the study period does not allow us to include more than 100 participants, the study would still have a reasonable power to detect a mean change of 0.5 DAS28-CRP units; a sample size of 100 pairs has a power of 80% (0.797).
This high-quality study had sufficient size and follow-up to have reasonable power for detecting an excess of leukemia, but it did not report on peak exposures or the risk of myeloid leukemia specifically.
Given that our average inter-marker distance (density) is 35 kb, we expect to have reasonable power to identify common variants of large effect associated with agronomic traits in association mapping.
