Table 2.
Applying sensitivity (Sen) and specificity (Sp) to theoretical populations of 1,000 patients
| 10% | 25% | 50% | 75% | |||||
|---|---|---|---|---|---|---|---|---|
| PPV | NPV | PPV | NPV | PPV | NPV | PPV | NPV | |
| MS | ||||||||
| Saliva i‐ATP | [94.0, 100] | [94.3, 97.0] | [97.6, 100] | [86.1, 90.5] | [98.8, 100] | [68.3, 75.1] | [99.2, 100] | [41.7, 50.2] |
| Plaque t‐ATP | [36.6, 51.7] | [96.1, 98.4] | [64.5, 75.5] | [90.4, 94.4] | [84.2, 90.5] | [77.1, 83.8] | [93.7, 97.0] | [52.9, 63.1] |
| LB | ||||||||
| Saliva i‐ATP | [24.8, 40.0] | [93.6, 96.7] | [51.4, 63.5] | [84.5, 89.5] | [75.9, 84.1] | [65.5, 72.9] | [89.8, 94.6] | [38.5, 47.4] |
| Plaque t‐ATP | [18.0, 26.9] | [95.1, 98.0] | [41.4, 51.0] | [88.2, 93.1] | [68.0, 75.7] | [72.7, 80.7] | [85.9, 90.8] | [47.0, 58.1] |
Note. Positive and negative predictive values (PPV and NPV) are dependent on the prevalence of a condition. Potential values (10–75%) of the prevalence of a high CRT threshold value (≥3) within the theoretical population are used. The 95% confidence intervals of the PPV and NPV mean are calculated from Youden index's Sen and Sp at the potential prevalence values. Confidence intervals displayed in bold place the mean values as equal or less predictive than 50%. ATP = adenosine triphosphate.