关键词: 样本量; 统计功效; 临床研究; 研究设计

Abstract: Appropriate sample size estimation was an important issue in clinical research design that clinical researchers pay attention to. Study objectives, study design, data type of the primary outcome, effect of interest, variability of the outcome measurement, type I error and power of test were key issues related to estimation of sample size in clinical studies. The main pitfalls of sample size estimation in clinical research design included direct determination of sample size without calculation, incompatibility between sample size estimation method and study design and objectives, and unreasonable parameter setting, etc.

Key words: Sample size; Statistical power; Clinical research; Study design