The EWMA control chart: properties and comparison with other quality-control procedures by computer simulation.
A quality-control chart based on exponentially weighted moving averages (EWMA) has, in the past few years, become a popular tool for controlling inaccuracy in industrial quality control. In this paper, I explain the principles of this technique, present some numerical examples, and by computer simulation compare EWMA with other control charts currently used in clinical chemistry. The EWMA chart offers a flexible instrument for visualizing imprecision and inaccuracy and is a good alternative to other charts for detecting inaccuracy, especially where small shifts are of interest. Detection of imprecision with EWMA charts, however, requires special modification.
Neubauer
A S
AS
Institut für Klinische Chemie und Pathobiochemie, Isar der Technischen Universítät München, Germany. A.S.Neubauer@lrz.tu-muenchen.de
D000465:Algorithms; D002624:Chemistry, Clinical / Q000706:statistics & numerical data; D003198:Computer Simulation; D011786:Quality Control; D012680:Sensitivity and Specificity