
限制性立方样条在临床研究数据分析中的应用
Application of restricted cubic splines in clinical research data analysis
临床研究中,时常需要构建回归模型分析自变量与因变量之间的关系。然而,回归模型大多要求自变量与因变量呈线性关联。当自变量与因变量不满足上述条件时,将连续型变量转化为分类变量会导致损失部分信息并可能引进新的偏倚。因此,这种情况下就需要构建样条回归直接拟合自变量与因变量之间的非线性关系,这种分析常用的方法就是限制性立方样条。本文从概念入手,就开展临床研究数据分析时,如何应用限制性立方样条拟合自变量与因变量之间的非线性关系进行阐述,以期为临床医务人员开展临床研究提供参考。
In clinical research, it is often necessary to construct regression models to analyze the relationship between independent variables and dependent variables. However, most regression models require a linear association of the independent variables with the dependent variable. When the independent variable and the dependent variable do not satisfy these conditions, transforming continuous variables into categorical variables will result in the loss of some information and may introduce new biases. Therefore, in this case, it is necessary to construct a spline regression to directly fit the nonlinear relationship between the independent variable and the dependent variable, and a common method for this analysis is the restricted cubic spline. This article starts with the concept of how to apply a restricted cubic spline to fit the nonlinear relationship between the independent variable and the dependent variable when analyzing clinical research data, so as to provide reference for clinical medical personnel to conduct clinical research.
限制性立方样条 / 非线性 / R语言 {{custom_keyword}} /
restricted cubic spline / nonlinear / the R programming language {{custom_keyword}} /
表1 RCS节点位置推荐 |
节点数量 | 节点1 | 节点2 | 节点3 | 节点4 | 节点5 | 节点6 | 节点7 |
---|---|---|---|---|---|---|---|
3 | 0.100 0 | 0.500 0 | 0.900 0 | ||||
4 | 0.050 0 | 0.350 0 | 0.650 0 | 0.950 0 | |||
5 | 0.050 0 | 0.275 0 | 0.500 0 | 0.725 0 | 0.950 0 | ||
6 | 0.050 0 | 0.230 0 | 0.410 0 | 0.590 0 | 0.770 0 | 0.950 0 | |
7 | 0.025 0 | 0.183 3 | 0.341 7 | 0.500 0 | 0.658 3 | 0.816 7 | 0.975 0 |
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