Table 4: Diagnostic features of the direct and calculated markers of the βAPB.

Marker Cutoff (pg/mL) Sensitivity (>85%) Specificity (>80%) ROC (>0.80) UP Aβ1-40 23.2 AD AD/HC 40.0 93.8 0.59 17.0 MCI MCI/HC 85.7 68.8 0.80 22.5 AD AD/MCI 40.0 71.4 0.35 DP Aβ1-40 63.8 AD AD/HC 46.7 81.3 0.59 63.8 MCI MCI/HC 85.7 81.3 0.81 72.2 AD AD/MCI 40.0 71.4 0.36 CB Aβ1-40 71.9 AD AD/HC 53.3 87.5 0.65 71.1 MCI MCI/HC 85.7 81.3 0.85 211.3 AD AD/MCI 13.3 100.0 0.40 UP Aβ1-42 10.28 AD AD/HC 46.7 87.5 0.65 9.2 MCI MCI/HC 85.7 81.3 0.90 67.4 AD AD/MCI 6.7 100.0 0.26 DP Aβ1-42 47.4 AD AD/HC 46.7 87.5 0.62 50.3 MCI MCI/HC 57.1 93.8 0.79 151.7 AD AD/MCI 6.7 100.0 0.35 CB Aβ1-42 76.9 AD AD/HC 40.0 100.0 0.74 59.8 MCI MCI/HC 100.0 50.0 0.72 71.3 AD AD/MCI 53.3 71.4 0.48 T40 (DP + CB) 132.7 AD AD/HC 53.3 81.3 0.60 132.7 MCI MCI/HC 85.7 81.3 0.83 550.8 AD AD/MCI 13.3 100 0.37 T42 (DP + CB) 115.8 AD AD/HC 53.3 87.5 0.71 103.3 MCI MCI/HC 100 50 0.77 113.7 AD AD/MCI 53.3 57.1 0.41 T-βAPB (T40 + T42) 235.5 AD AD/HC 53.3 81.3 0.65 235.5 MCI MCI/HC 85.7 81.3 0.84 778.1 AD AD/MCI 13.3 100 0.38

Highlighted in bold are the results that met the criterion considered suitable as figure in the heading. PPV: positive predictive value. NPV: negative predictive value. ROC: area under the receiver operating characteristic curve.