Considerations on sample size and power calculations in randomized clinical trials.
Many studies in orthopaedics and sports medicine have not considered sample size or statistical power as important issues in study design. This article addresses the importance of a sample size calculation in randomized clinical trials and the components of the calculations that researchers must consider in their preliminary planning of an investigation. The types of data being collected, level of significance, types I and II errors, and power are also addressed.
Karlsson
Jon
J
Sahlgrenska University Hospital/Ostra, Gothenburg, Sweden.
Engebretsen
Lars
L
Dainty
Katie
K
D006801:Humans; D016032:Randomized Controlled Trials as Topic / Q000706:statistics & numerical data*; D012107:Research Design; D018401:Sample Size