阈值效应分析的应用和R软件实现  

The threshold effect analysis:application and implementation in R software

作　　者：盛松 张艳虹[1] 环璐瑶 郭曼萍 马杭琨 高洪阳 赵阳[5] 黄烨[1] Sheng Song;Zhang Yanhong;Huan Luyao;Guo Manping;Ma Hangkun;Gao Hongyang;Zhao Yang;Huang Ye(Emergency Department,Xiyuan Hospital,China Academy of Chinese Medical Science,Beijing 100091,China.;不详)

机构地区：[1]中国中医科学院西苑医院急诊科,北京100091 [2]北京中医药大学研究生院,北京100029 [3]中国中医科学院博士后流动站,北京100700 [4]亚宝药业集团股份有限公司博士后工作站,运城044000 [5]中国中医科学院西苑医院临床药理研究所,北京100091

出　　处：《中国循证心血管医学杂志》2025年第2期161-163,174,共4页Chinese Journal of Evidence-Based Cardiovascular Medicine

基　　金：中国中医科学院科技创新工程课题(CI2021A02905);中国中医科学院西苑医院“青师计划”(2022QS-14)。

摘　　要：当一研究因素超过某一阈值后,其作用大小或/和方向发生显著变化称为阈值效应。阈值效应分析作为一种统计工具,可以推测病变的发生、发展和预后,具有重大意义。目前尚缺乏开源、免费、简便、有效的工具实现阈值效应分析,确定阈值的过程复杂、工作量大,需要较高的编程技巧,因此本文通过实例展示如何通过编写的R脚本文件、精简代码等流程简化这一过程并且降低对编程技巧的要求,使非统计专业人员也能够进行阈值效应分析。首先,通过平滑曲线拟合观察研究因素(X)与结局(Y)间是否存在非线性关系,如果目测存在阈值,采用最大似然法、递归法、分段线性模型和似然比检验确定阈值、阈值前后两段效应量和前后两段的效应量是否显著。When the effect size or direction of a study factor changes significantly after surpassing a certain threshold,this is known as a threshold effect.As a statistical tool,the threshold effect analysis can predict the occurrence,development and prognosis of diseases,which is of great significance.However,there is no opensource,free,simple and effective tool for the threshold effect analysis.Determining threshold values is complicated,requiring a heavy workload and high programming skills.Therefore,this paper demonstrates how to streamline this process and reduce the requirements on programming skills with written R script files and simplified codes by example,and enable non-statistical professionals to perform the threshold effect analysis.First,smooth curve fitting was used to observe whether there is a nonlinear relationship between the study factor(X)and the outcome(Y).If there is a visual threshold,the maximum likelihood method,recursion method,piecewise linear model and likelihood ratio test were carried out to determine the threshold,the effect size and statistical significance before and after the threshold.

关 键 词：阈值效应 最大似然法 递归法 分段线性回归 R软件 

分 类 号：R4[医药卫生—临床医学]