title: Sample size considerations for clinical research studies in nuclear cardiology.
abstract: Sample size calculation is an important element of research design that investigators need to consider in the planning stage of the study. Funding agencies and research review panels request a power analysis, for example, to determine the minimum number of subjects needed for an experiment to be informative. Calculating the right sample size is crucial to gaining accurate information and ensures that research resources are used efficiently and ethically. The simple question "How many subjects do I need?" does not always have a simple answer. Before calculating the sample size requirements, a researcher must address several aspects, such as purpose of the research (descriptive or comparative), type of samples (one or more groups), and data being collected (continuous or categorical). In this article, we describe some of the most frequent methods for calculating the sample size with examples from nuclear cardiology research, including for t tests, analysis of variance (ANOVA), non-parametric tests, correlation, Chi-squared tests, and survival analysis. For the ease of implementation, several examples are also illustrated via user-friendly free statistical software.
authors.affiliation: Department of Biostatistics, Mailman School of Public Health, Columbia University, New York, NY, USA. cc3780@cumc.columbia.edu.
authors.forename: Cody
authors.initials: C
authors.lastname: Chiuzan
authors.affiliation: Department of Biostatistics, Mailman School of Public Health, Columbia University, New York, NY, USA.
authors.forename: Erin A
authors.initials: EA
authors.lastname: West
authors.affiliation: Department of Biostatistics, Mailman School of Public Health, Columbia University, New York, NY, USA.
authors.forename: Jimmy
authors.initials: J
authors.lastname: Duong
authors.affiliation: Department of Biostatistics, Mailman School of Public Health, Columbia University, New York, NY, USA.
authors.forename: Ken Y K
authors.initials: KY
authors.lastname: Cheung
authors.affiliation: Division of Cardiology, Departments of Medicine and Radiology, Columbia University Medical Center and New York-Presbyterian Hospital, New York, 10032, USA.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Einstein
mesh_terms: D002309:Cardiology / Q000639:trends*; D002986:Clinical Trials as Topic / Q000379:methods*; D003198:Computer Simulation; D003627:Data Interpretation, Statistical; D015233:Models, Statistical; D009683:Nuclear Medicine / Q000379:methods*; D012107:Research Design; D018401:Sample Size
keywords: Sample size; clinical research; nuclear cardiology