Importantly, these statistics are based on different characteristics of the data and are powered to identify different types of selective sweeps.
However, it's unclear whether either study will be sufficiently powered to identify multivariable predictors of ESRD because those analyses depend on the number of events, not the number of patients.
We plan to recruit 120 participants and we have designed this study to be sufficiently powered to identify a prolongation of pregnancy.
For example, blood levels of TH vary among individuals (Andersen et al. 2002, 2003), which will affect the number of samples required for such a study to be sufficiently powered to identify associations of interest.
In particular, we chose not to stratify patients into smaller subgroups, such as individual Hunt-Hess scores, because the resulting groups would then be inadequately powered to identify reasonable differences in outcomes.
While the proposed sample size is small, the repeated measures design ensures our study is sufficiently powered to identify medium effects on our primary outcome variable, and provide preliminary assessment of the mechanisms of change.
Changes in antimicrobial drug resistance during the 1-year period might have been lower than the level of detection that this study was statistically powered to identify.
Nonetheless it still only screened <15% of the human genome, and was only powered to identify moderately large genetic effects compared with the magnitude of genetic associations that are typically found in common diseases.
Although sarcoma histology is recognized as a prognostic factor, most studies of retroperitoneal sarcomas report results combining multiple histologies and are inadequately powered to identify prognostic factors specific to a particular histology.
Hundreds of these were not identified by local-eQTL analyses in our F2 and HMDP cohorts, even though these approaches were sufficiently powered to identify the majority of such effects.
