Table 1.
The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and efficiency for CSF RT-QuIC and 14-3-3 in neuropathologically confirmed sCJD for both the exploratory and confirmatory groups. Figures are given for each of the PRNP codon 129 genotypes of sCJD (MM: homozygous for methionine; MV heterozygous for methionine and valine and VV: homozygous for valine). The figures given are the number of positive or negative results over the total number of samples investigated. Efficiency was defined as:
| Exploratory Group | Confirmatory Group | Both Groups | ||||
|---|---|---|---|---|---|---|
| RT-QuIC | 14-3-3 | RT-QuIC | 14-3-3 | RT-QuIC | 14-3-3 | |
| sCJD | 51/56 | 52/56 | 58/67 | 64/67 | 109/123 | 116/123 |
| sCJD controls | 1/52 | 23/52 | 0/51 | 13/51 | 1/103 | 36/103 |
| Sensitivity (All) | 91% | 93% | 87% | 96% | 89% | 94% |
| Sensitivity (MM) | 90% | 97% | 90% | 93% | 90% | 95% |
| Sensitivity (MV) | 88% | 82% | 88% | 100% | 88% | 95% |
| Sensitivity (VV) | 100% | 100% | 92% | 100% | 95% | 100% |
| Specificity | 98% | 56% | 100% | 75% | 99% | 65% |
| PPV | 98% | 69% | 100% | 83% | 99% | 76% |
| NPV | 91% | 88% | 85% | 93% | 88% | 91% |
| Efficiency | 94% | 75% | 92% | 86% | 93% | 81% |