Comparison of 2 methods for calculating adjusted survival curves from proportional hazards models
Comparison of 2 methods for calculating adjusted survival curves from proportional hazards models
复制标题
DOI：
10.1001/jama.286.12.1494
复制
发表时间：
2001-09-26
影响因子：
120.7
通讯作者：
Knudtson, ML
中科院分区：
文献类型：
--
作者：
Ghali, WA;Quan, HD;Knudtson, ML
背景校正生存曲线经常出现在医学研究文章中。最常用的计算此类曲线的方法是协变量平均值法，其中协变量的平均值输入比例风险回归方程。使用这种方法是广泛的，尽管公布的关注的有效性产生curves.Objective比较的协变量方法的平均值不太广泛使用的校正组预后的方法在分析中评估生存的糖尿病患者和非糖尿病患者。在后一种方法中，计算每个协变量水平的生存曲线，之后计算平均生存曲线作为每个协变量水平的生存曲线的加权平均。设计、设置和患者分析队列研究数据，来自11468名阿尔伯塔居民，在1995年1月1日至12月31日期间接受心导管插入术。1996.主要结果测量有糖尿病与无糖尿病的患者心导管插入术后3年的粗生存率和风险调整生存率，采用协变量平均值法与校正组预后法进行分析。结果根据协变量平均值法，有糖尿病和无糖尿病患者的1044天校正生存率分别为94.1%和94.9%，校正生存曲线高于未校正曲线。与校正组预后的方法，相应的生存值分别为91.3%和92.4%，曲线下降之间的uncorrectedcurrent.Conclusions误导调整后的生存曲线，导致使用协变量的平均值的分析方法为我们的数据。我们建议使用校正的组预后方法来计算风险调整曲线。
Context Adjusted survival curves are often presented in medical research articles. The most commonly used method for calculating such curves is the mean of covariates method, in which average values of covariates are entered into a proportional hazards regression equation. Use of this method is widespread despite published concerns regarding the validity of resulting curves.Objective To compare the mean of covariates method to the less widely used corrected group prognosis method in an analysis evaluating survival in patients with and without diabetes. In the latter method, a survival curve is calculated for each level of covariates, after which an average survival curve is calculated as a weighted average of the survival curves for each level of covariates.Design, Setting, and Patients Analysis of cohort study data from 11468 Alberta residents undergoing cardiac catheterization between January 1, 1995, and December 31, 1996.Main Outcome Measures Crude and risk-adjusted survival for up to 3 years after cardiac catheterization in patients with vs without diabetes, analyzed by the mean of covariates method vs the corrected group prognosis method.Results According to the mean of covariates method, adjusted survival at 1044 days was 94.1% and 94.9% for patients with and without diabetes, respectively, with misleading adjusted survival curves that fell above the unadjusted curves. With the corrected group prognosis method, the corresponding survival values were 91.3% and 92.4%, with curves that fell more appropriately between the unadjusted curves.Conclusions Misleading adjusted survival curves resulted from using the mean of covariates method of analysis for our data. We recommend using the corrected group prognosis method for calculating risk-adjusted curves.