TY - JOUR
T1 - Sample Size Calculations
AU - Noordzij, M.
AU - Dekker, F.W.
AU - Zoccali, C.
AU - Jager, K.J.
PY - 2011
Y1 - 2011
N2 - The sample size is the number of patients or other experimental units that need to be included in a study to answer the research question. Pre-study calculation of the sample size is important; if a sample size is too small, one will not be able to detect an effect, while a sample that is too large may be a waste of time and money. Methods to calculate the sample size are explained in statistical textbooks, but because there are many different formulas available, it can be difficult for investigators to decide which method to use. Moreover, these calculations are prone to errors, because small changes in the selected parameters can lead to large differences in the sample size. This paper explains the basic principles of sample size calculations and demonstrates how to perform such a calculation for a simple study design. Copyright (C) 2011 S. Karger AG, Basel
AB - The sample size is the number of patients or other experimental units that need to be included in a study to answer the research question. Pre-study calculation of the sample size is important; if a sample size is too small, one will not be able to detect an effect, while a sample that is too large may be a waste of time and money. Methods to calculate the sample size are explained in statistical textbooks, but because there are many different formulas available, it can be difficult for investigators to decide which method to use. Moreover, these calculations are prone to errors, because small changes in the selected parameters can lead to large differences in the sample size. This paper explains the basic principles of sample size calculations and demonstrates how to perform such a calculation for a simple study design. Copyright (C) 2011 S. Karger AG, Basel
U2 - https://doi.org/10.1159/000322830
DO - https://doi.org/10.1159/000322830
M3 - Article
C2 - 21293154
SN - 1660-2110
VL - 118
SP - C319-C323
JO - Nephron. Clinical practice
JF - Nephron. Clinical practice
IS - 4
ER -