title: Considerations on sample size and power calculations in randomized clinical trials.
abstract: 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.
authors: Sahlgrenska University Hospital/Ostra, Gothenburg, Sweden.
authors: Jon
authors: J
authors: Karlsson
authors: Lars
authors: L
authors: Engebretsen
authors: Katie
authors: K
authors: Dainty
mesh_terms: D006801:Humans; D016032:Randomized Controlled Trials as Topic / Q000706:statistics & numerical data*; D012107:Research Design; D018401:Sample Size