Retrospective Study
Copyright ©The Author(s) 2023.
World J Orthop. Mar 18, 2023; 14(3): 146-154
Published online Mar 18, 2023. doi: 10.5312/wjo.v14.i3.146
Figure 1
Figure 1 Minimum sample size calculation. A: Formula; B: Calculation process for this study. p1, p2: Proportion (incidence) of groups #1 and #2; Δ = |p2-p1| = absolute difference between two proportions; n1: Sample size for group #1; n2: Sample size for group #2; α: Probability of type I error; β: Probability of type II error; z: Critical Z value for a given α or β; K: Ratio of sample size for group #2 to group #1.