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 ...

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 ...

Define statistical power List the potential consequences of doing a study that has low power, and also a study that has too much power. Explain what a type 1 and type ...

Cluster randomized trials in health care may involve three instead of two levels, for instance, in trials where different interventions to improve quality of care are compared. In such trials, the ...

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 ...

Precedents set in the historic Barr case continue to raise questions over suitable sample-size criteria. "... the number of retests performed before a firm concludes that an unexplained out of ...

Jason Fernando is a professional investor and writer who enjoys tackling and communicating complex business and financial problems. Erika Rasure is globally-recognized as a leading consumer economics ...