Diagnostic accuracy of PM-AHIs for AHI thresholds of ≥5/h, ≥15/h and ≥30/h in all subjects
| Sens (%) | Spe (%) | PPV (%) | NPV (%) | +LR | +PTP (%) | −LR | −PTP (%) | CC (%) | |
|---|---|---|---|---|---|---|---|---|---|
| AHI ≥5/h (n=232; pre-test probability=74.36%) | |||||||||
| PM-AHI1 | 99.14 | 81.25 | 93.88 | 97.01 | 5.29 | 93.88 | 0.01 | 2.82 | 94.55 |
| PM-AHI2 | 100.00 | 22.50 | 78.91 | 100.00 | 1.29 | 78.91 | 0.00 | 0.00 | 80.13 |
| PM-AHI3 | 77.16 | 98.75 | 99.44 | 59.85 | 61.72 | 99.44 | 0.23 | 40.01 | 82.69 |
| PM-AHI4 | 98.71 | 51.25 | 85.45 | 93.18 | 2.02 | 85.41 | 0.03 | 8.00 | 86.54 |
| AHI ≥15/h (n=152; pre-test probability=48.72%) | |||||||||
| PM-AHI1 | 90.13 | 96.25 | 95.80 | 91.12 | 24.04 | 95.81 | 0.10 | 8.68 | 93.27 |
| PM-AHI2 | 99.34 | 76.25 | 79.89 | 99.19 | 4.18 | 79.88 | 0.01 | 0.94 | 87.50 |
| PM-AHI3 | 53.95 | 100.00 | 100.00 | 69.57 | * | 100.00 | 0.46 | 30.41 | 77.56 |
| PM-AHI4 | 77.63 | 96.88 | 95.93 | 82.01 | 24.84 | 95.93 | 0.23 | 17.93 | 87.50 |
| AHI ≥30/h (n=74; pre-test probability=23.72%) | |||||||||
| PM-AHI1 | 70.27 | 100.00 | 100.00 | 91.54 | * | 100.00 | 0.30 | 8.53 | 92.95 |
| PM-AHI2 | 89.19 | 95.80 | 86.84 | 96.61 | 21.23 | 86.85 | 0.11 | 3.31 | 94.23 |
| PM-AHI3 | 29.73 | 100.00 | 100.00 | 82.07 | * | 100.00 | 0.70 | 17.88 | 83.33 |
| PM-AHI4 | 50.00 | 99.58 | 97.37 | 86.50 | 119.00 | 97.37 | 0.50 | 13.46 | 87.82 |
*Infinite value.
AHI, apnoea–hypopnoea index; CC, correctly classified; −LR, negative likelihood ratio; +LR, positive likelihood ratio; NPV, negative predictive value; PM-AHI, portable monitors apnoea–hypopnoea index; PPV, positive predictive value; −PTP, negative post-test probability; +PTP, positive post-test probability; Sens, sensitivity; Spe, specificity.