Table 4.
Ten-fold cross-validated performance of final parsimonious models for prediction of SDB at the first study visit (V1), third study visit (V3), and new onset SDB at the third study visit (V3) at selected specificities. Predictor variables are transformed BMI at V1, maternal age at V1, and frequent snoring at V1 for SDB at V1; and transformed BMI at V3, maternal age at V3, and frequent snoring at V3 for both SDB and new onset SDB at V3. BMI was transformed using a Box-Cox power transformation with λ = −1.25 (see methods). Frequent snoring was defined as snoring ≥3 days per week during the 4 weeks prior to the visit.
| SDB model |
nominal specificity |
predicted probability cutoff |
percentage of participants |
Sens | Spec | PPV | NPV | LR+ | LR- |
|---|---|---|---|---|---|---|---|---|---|
| V1 | 50% | ≥0.008 | 51.5% | 92.9% | 50.0% | 6.3% | 99.5% | 1.86 | 0.14 |
| 55% | ≥0.010 | 46.6% | 92.0% | 55.0% | 6.9% | 99.5% | 2.05 | 0.14 | |
| 60% | ≥0.013 | 41.8% | 92.0% | 60.0% | 7.7% | 99.5% | 2.30 | 0.13 | |
| 65% | ≥0.017 | 36.9% | 90.3% | 65.1% | 8.6% | 99.5% | 2.58 | 0.15 | |
| 70% | ≥0.022 | 32.1% | 89.4% | 70.0% | 9.8% | 99.5% | 2.98 | 0.15 | |
| 75% | ≥0.029 | 27.1% | 86.7% | 75.0% | 11.2% | 99.4% | 3.47 | 0.18 | |
| 80% | ≥0.038 | 22.1% | 80.5% | 80.0% | 12.8% | 99.1% | 4.03 | 0.24 | |
| 85% | ≥0.055 | 17.0% | 72.6% | 85.0% | 15.0% | 98.8% | 4.84 | 0.32 | |
| 90% | ≥0.082 | 11.8% | 61.1% | 90.0% | 18.2% | 98.5% | 6.11 | 0.43 | |
| 95% | ≥0.139 | 6.5% | 46.9% | 95.0% | 25.5% | 98.0% | 9.41 | 0.56 | |
| V3 | 50% | ≥0.031 | 53.4 % | 91. 6% | 50. 0% | 14. 1% | 98. 5% | 1.8 3 | 0.1 7 |
| 55% | ≥0.037 | 48.6% | 89.1% | 55.0% | 15.1% | 98.3% | 1.98 | 0.20 | |
| 60% | ≥0.045 | 43.8% | 86.1% | 60.0% | 16.2% | 98.0% | 2.15 | 0.23 | |
| 65% | ≥0.053 | 39.0% | 84.2% | 65.0% | 17.7% | 97.9% | 2.41 | 0.24 | |
| 70% | ≥0.065 | 34.1% | 80.7% | 70.0% | 19.5% | 97.6% | 2.69 | 0.28 | |
| 75% | ≥0.080 | 29.2% | 76.7% | 75.0% | 21.6% | 97.3% | 3.07 | 0.31 | |
| 80% | ≥0.101 | 24.2% | 71.3% | 80.0% | 24.2% | 96.9% | 3.57 | 0.36 | |
| 85% | ≥0.126 | 19.0% | 63.9% | 85.0% | 27.7% | 96.3% | 4.27 | 0.42 | |
| 90% | ≥0.170 | 13.6% | 54.5% | 90.0% | 32.8% | 95.7% | 5.45 | 0.51 | |
| 95% | ≥0.258 | 8.0% | 41.6% | 95.0% | 42.9% | 94.8% | 8.37 | 0.61 | |
| new onset V3 | 50% | ≥0.027 | 52.4 % | 90. 1% | 50. 0% | 10. 2% | 98. 8% | 1.8 0 | 0.2 0 |
| 55% | ≥0.031 | 47.4% | 86.3% | 55.0% | 10.8% | 98.4% | 1.92 | 0.25 | |
| 60% | ≥0.036 | 42.5% | 83.2% | 60.0% | 11.6% | 98.3% | 2.08 | 0.28 | |
| 65% | ≥0.042 | 37.7% | 80.9% | 65.0% | 12.7% | 98.2% | 2.31 | 0.29 | |
| 70% | ≥0.050 | 32.8% | 77.1% | 70.0% | 14.0% | 98.0% | 2.57 | 0.33 | |
| 75% | ≥0.061 | 27.8% | 72.5% | 75.0% | 15.5% | 97.7% | 2.90 | 0.37 | |
| 80% | ≥0.075 | 22.7% | 66.4% | 80.0% | 17.3% | 97.4% | 3.32 | 0.42 | |
| 85% | ≥0.094 | 17.4% | 56.5% | 85.0% | 19.2% | 96.9% | 3.77 | 0.51 | |
| 90% | ≥0.128 | 12.1% | 45.8% | 90.0% | 22.5% | 96.3% | 4.60 | 0.60 | |
| 95% | ≥0.187 | 6.7% | 33.6% | 95.0% | 29.9% | 95.8% | 6.77 | 0.70 |
Sens = sensitivity, Spec = specificity, PPV = positive, predictive value, NPV = negative predictive value, LR+ = positive likelihood ratio, LR− = negative likelihood ratio.