Walz Brigitte, Fierz Walter
Kantonsspital Graubünden, Zentrallabor, Chur.
Labormedizinisches Zentrum Dr. Risch, Schaan, Liechtenstein.
Ther Umsch. 2015 Feb;72(2):130-5. doi: 10.1024/0040-5930/a000655.
Reference values are generally used to allow a decision on whether a laboratory value is in the normal range or if it mirrors a pathological process. This decision is especially difficult to take, when the pathological process is just starting and the values are relatively close to the normal range. Particularly in this phase, the decision is extremely important. Harris and later on Fraser have realized that there are two variables that contribute to the credibility and significance of a measured analyte. 1. The imprecision of the measurement itself. These values have become relatively low in recent years: they amount to values between 1 and 5 %. 2. The within person biological variability, which can be 100 % or more. Both variables combined yield the "reference change value" (RCV) to define the minimal significant difference between two measurements at different time points. When using this concept, differences between two measurements can be detected before the normal range is exceeded. For any given patient the reference values of a population is actually not of primary concern. It is important to know that his personal data exceed his personal normal range, which is dependent on RCV. For many analytes in clinical chemistry and hematology the use of RCV rather than the normal range as reference improves the decision making process in a clinical setting.
参考值通常用于判断实验室检测值是否在正常范围内，或者是否反映了病理过程。当病理过程刚刚开始且检测值相对接近正常范围时，做出这种判断尤其困难。特别是在这个阶段，该判断极为重要。哈里斯以及后来的弗雷泽认识到，有两个变量会影响所测分析物的可信度和重要性。1. 测量本身的不精密度。近年来，这些值已经相对较低：介于1%至5%之间。2. 个体内部的生物学变异，其可能达到100%或更高。这两个变量相结合得出“参考变化值”（RCV），以定义不同时间点两次测量之间的最小显著差异。使用这一概念时，可以在超出正常范围之前检测到两次测量之间的差异。对于任何特定患者而言，群体的参考值实际上并非首要关注点。重要的是要知道其个人数据超出了其个人正常范围，而这取决于参考变化值。对于临床化学和血液学中的许多分析物，使用参考变化值而非正常范围作为参考，可改善临床环境中的决策过程。
