Sadler W A, Smith M H, Legge H M
Department of Nuclear Medicine, Christchurch Hospital, New Zealand.
Clin Chem. 1988 Jun;34(6):1058-61.
A three-parameter model for directly estimating imprecision profiles from replicated immunoassay results is compared with a six-parameter indirect profile model obtained by the usual method of combining error in the raw response measurements with the slope of the standard curve. Direct estimation is likely to be less reliable when based on the limited data collected from a single assay, and may underestimate variability at high concentrations when many results are clustered at the upper end of the concentration range. However, at concentrations near the assay detection limit (often a region of particular interest), direct estimation is superior to the indirect method if a logistic or related function is used as the standard curve model. Direct estimation of imprecision profiles has useful application whenever the internal details of an assay system are not readily available, for example, in analysis of data collected in external surveys.
一种用于从重复免疫测定结果直接估计不精密度曲线的三参数模型，与通过将原始响应测量中的误差与标准曲线斜率相结合的常规方法获得的六参数间接曲线模型进行了比较。当基于从单次测定收集的有限数据进行直接估计时，其可靠性可能较低，并且当许多结果聚集在浓度范围的上限时，可能会低估高浓度下的变异性。然而，在接近测定检测限的浓度（通常是特别感兴趣的区域），如果使用逻辑函数或相关函数作为标准曲线模型，直接估计优于间接方法。只要测定系统的内部细节不容易获得，例如在外部调查收集的数据的分析中，不精密度曲线的直接估计就有有用的应用。
