Table 4.
Comparison of αSyn_RT-QuIC results between ITA-lab and USA-lab
| PD | MSA-P | MSA-C | HS | |||||
|---|---|---|---|---|---|---|---|---|
| ITA-lab | USA-lab | ITA-lab | USA-lab | ITA-lab | USA-lab | ITA-lab | USA-lab | |
| Samples analyzed | 13 | 13 | 20 | 20 | 10 | 10 | 11 | 11 |
| αSynD seeding activity | 9 | 9 | 18 | 18 | 0 | 1 | 0 | 1 |
| Mean fluorescence at the time threshold % (SD) | 56.46 (39.88) | 41.85 (42.41) | 56.70 (30.76) | 46.10 (32.20) | 5.90 (0.99) | 11.00 (19.40) | 6.18 (1.07) | 10.00 (19.29) |
| Mean time at fluorescence threshold (SD) | 9.31 (1.19) | 15.93 (4.41) | 10.54 (1.17) | 17.23 (3.29) | NA | NA | NA | NA |
| Seeding activity vs clinical diagnosis (sensitivity) | 69% | 69% | 90% | 90% | 0% | 10% | NA | NA |
| Disease-specific interrater agreement between labs | 100% | 100% | 90% | 91% | ||||
| Overall interrater agreement between labs | 96% (Kappa = 0.93, 95% CI 0.83–1.00) | |||||||