Levy W C, Hay K L, Bull B S
Am J Clin Pathol. 1986 Jun;85(6):719-21. doi: 10.1093/ajcp/85.6.719.
A comparison of the Bull's algorithm (XB) for quality control with a system based on analysis of preserved blood suggested that the preserved blood approach was the more sensitive method. However, the procedures compared were not equivalent. Four control blood samples analyzed by a multirule Shewhart approach were compared with a single XB result. Consequently, a reexamination of the relative sensitivities of the two methods was undertaken with a multirule Shewhart approach applied to both methods. On this basis, both methods have equivalent sensitivity. Once the XB mean reflects the shifted mean (and at all times with a drifting mean), either the XB algorithm or the analysis of preserved blood will detect systematic errors with similar probability using similar control rules.
将用于质量控制的布尔算法（XB）与基于保存血液分析的系统进行比较，结果表明保存血液法是更灵敏的方法。然而，所比较的程序并不等效。通过多规则休哈特方法分析的4份对照血样与单个XB结果进行了比较。因此，采用多规则休哈特方法对两种方法进行了重新检验，以确定它们的相对灵敏度。在此基础上，两种方法具有同等的灵敏度。一旦XB均值反映了偏移均值（并且在均值漂移的所有情况下），使用相似的控制规则，XB算法或保存血液分析将以相似的概率检测到系统误差。
