Petersen P H, Stöckl D, Westgard J O, Sandberg S, Linnet K, Thienpont L
Department of Clinical Biochemistry, Odense University Hospital, Denmark.
Clin Chem Lab Med. 2001 Jul;39(7):589-95. doi: 10.1515/CCLM.2001.094.
A series of models for handling and combining systematic and random variations/errors are investigated in order to characterize the different models according to their purpose, their application, and discuss their flaws with regard to their assumptions. The following models are considered 1. linear model, where the random and systematic elements are combined according to a linear concept (TE = absolute value(bias) + z x sigma), where TE is total error, bias is the systematic error component, sigma is the random error component (standard deviation or coefficient of variation) and z is the probability factor; 2. squared model with two sub-models of which one is the classical statistical variance model and the other is the GUM (Guide to Uncertainty in Measurements) model for estimating uncertainty of a measurement; 3. combined model developed for the estimation of analytical quality specifications according to the clinical consequences (clinical outcome) of errors. The consequences of these models are investigated by calculation of the functions of transformation of bias into imprecision according to the assumptions and model calculations. As expected, the functions turn out to be rather different with considerable consequences for these types of transformations. It is concluded that there are at least three models for combining systematic and random variation/errors, each created for its own specific purpose, with its own assumptions and resulting in considerably different results. These models should be used according to their purposes.
研究了一系列用于处理和组合系统误差和随机误差的模型，以便根据其目的、应用来描述不同的模型，并讨论其假设方面的缺陷。考虑了以下模型：1. 线性模型，其中随机和系统元素根据线性概念进行组合（TE = 偏差绝对值 + z×标准差），其中TE是总误差，偏差是系统误差分量，标准差是随机误差分量（标准差或变异系数），z是概率因子；2. 平方模型，有两个子模型，一个是经典统计方差模型，另一个是用于估计测量不确定度的GUM（测量不确定度指南）模型；3. 为根据误差的临床后果（临床结果）估计分析质量规范而开发的组合模型。根据假设和模型计算，通过计算偏差向不精密度转换的函数来研究这些模型的后果。不出所料，这些函数差异很大，对这些类型的转换有相当大的影响。得出的结论是，至少有三种用于组合系统误差和随机误差的模型，每种模型都为其特定目的而创建，有自己的假设，并且结果差异很大。应根据其目的使用这些模型。
