Kornreich F, Holt J, Barnard A C, Snoeck J, Kramer J, Kornreich J, Reygaert P
Eur J Cardiol. 1976 Jun;4(2):131-40.
Two widely used orthogonal corrected 3-lead system - the Frank and the McFee systems - were studied in order to evaluate whether a significant difference in diagnostic performance could be observed; in the case of a positive answer, we would be able to advocate one system instead of the other. No such overall difference was noticed. Although +/- 17% discrepancies were found on the individual classification level (a patient correctly classified with system A and missed with system B and conversely), the practical implication is negligible since each system is responsible for +/- half of these discrepancies. Multivariate analysis, as already largely proved by Pipberger's group, drastically ameliorates the diagnostic results. Special caution has been given to the number of selected discriminators in order to enhance repeatability of the results; the reproducibility, using the approach developed by Cornfield, was found excellent. Some particular features as to the choice and location of the best discriminators were found somewhat puzzling by the autors but no deterministic explanation could be offered: the selection of the variables, indeed, rested on statistical bases and not on the (sometimes fragmentary) knowledge of what is going on in the heart and how these events relate to surface waveform patterns.
为了评估在诊断性能上是否能观察到显著差异，对两种广泛使用的正交校正三导联系统——弗兰克系统和麦克菲系统进行了研究；如果答案是肯定的，我们就能推荐使用其中一种系统而非另一种。未发现此类总体差异。尽管在个体分类层面发现了±17%的差异（即一名患者在系统A中被正确分类而在系统B中被漏诊，反之亦然），但实际影响可忽略不计，因为每个系统对这些差异的正负各占一半左右。正如皮普伯格团队已充分证明的那样，多变量分析极大地改善了诊断结果。为了提高结果的可重复性，对所选鉴别器的数量给予了特别关注；使用科恩菲尔德开发的方法，发现可重复性极佳。作者们发现，关于最佳鉴别器的选择和位置的一些特定特征有些令人费解，但无法给出确定性解释：实际上，变量的选择基于统计学依据，而非基于对心脏内部情况以及这些事件与体表波形模式如何关联的（有时是零碎的）了解。
