title: Sample size matters: A guide for urologists.
abstract: Understanding sample size calculation is vitally important for planning and conducting clinical research, and critically appraising literature. The purpose of this paper is to present basic statistical concepts and tenets of study design pertaining to calculation of requisite sample size. This paper also discusses the significance of sample size calculation in the context of ethical considerations. Scenarios applicable to urology are utilized in presenting concepts.
authors.affiliation: Division of Urology, University of Texas Medical School at Houston, Houston, Texas, USA.
authors.forename: Peter
authors.initials: P
authors.lastname: Hinh
authors.forename: Steven E
authors.initials: SE
authors.lastname: Canfield