Sample sizes based on three popular indices of risks

• 作者: Bokai Wang Changyong Feng Hongyue Wang Jinyuan Liu Xin M Tu
• 来源期刊: 综合精神医学(英文)
• 学科: 医学
• 关键词: SIZE SAMPLE DERIVE indices
• 年，卷（期）: zhjsyxyw_2018,（6）
• 页码范围: 150-152
• 页数: 3页
• 分类号: R

摘要

Sample size justification is a very crucial part in the design of clinical trials. In this paper, the authors derive a new formula to calculate the sample size for a binary outcome given one of the three popular indices of risk difference.The sample size based on the absolute difference is the fundamental one, which can be easily used to derive sample size given the risk ratio or OR.