We comment here on a recent paper in this journal, on a non-monotone transformation of biomarkers aimed at improving diagnostic accuracy. We highlight that, in a binary classification problem, the proposed transformation finds its motivation in the Neyman-Pearson lemma, so that the underlying approach is very general and it is applicable to many parametric families, other than the normal one.
Keywords: Diagnostic medicine; Neyman–Pearson lemma; ROC analysis; classification accuracy.