We present a simple sample-size formula for weighted log-rank statistics applied to clustered survival data with variable cluster sizes and arbitrary treatment assignments within clusters. This ...

Power analyses and sample size calculations are important parts of many research projects. Often, before data are even collected, it is necessary to calculate and justify the required sample size for ...

Back in the day, we learned in statistics that you need a sample size of at least 2% of the size of population to make statistically significant conclusions about the behavior of the population. In ...

Investigator: Right, here is the data set. What is the P value? Statistician: Oh, hello again. Look, I have some concerns about how the endpoint was assessed... Investigator: Fine, I'll add a sentence ...

Precedents set in the historic Barr case continue to raise questions over suitable sample-size criteria. The sample size needed to investigate an out-of-specification (OOS) result continues to be a ...

Reviewed by Eric Estevez It's possible to calculate the standard error in MATLAB by running a one-line command. Standard ...

In two-stage adaptive treatment strategies, patients receive an induction treatment followed by a maintenance therapy, given that the patient responded to the induction treatment they received. To ...