NEFL and Parkinson disease: As seen from Table 3, the best differentiating panel between PD and APD was formed by the combination of plasma NfL, Aβ42, and total tau, which yielded an ideal sensitivity and specificity of 100% (AUC = 1.000), whereas the combination of Aβ42 and total tau without NfL revealed an AUC of 0.963 with a sensitivity of 95% and a specificity of 91.1%.