Was the study big enough? Two "cafe" rules

Glasziou, Paul; Doll, Helen
November 2007
ACP Journal Club;Nov/Dec2007, Vol. 147 Issue 3, pA8
Academic Journal
The authors' offer their opinion on the magnitude of clinical studies. They opine that small studies do not provide a statistically significant effect. They state that smaller studies are more susceptible to random errors, as compared to longer studies and have tighter CIs. They also discuss the power of research works and describe the sample size requirements for different types of studies.


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