Table 2.
App performance based on individual and combined app variables
| AUROC (95% CI) | Sensitivity | Specificity | PPVa | NPVa | |
|---|---|---|---|---|---|
| All app variables | 89.9 (3.0) | 87.8 (4.9) | 80.8 (2.3) | 40.6 (8.8) | 97.8 (99.7) |
| Facing forward | 83.8 (3.7) | 87.8 (4.4) | 65.9 (2.6) | 27.7 (5.2) | 97.3 (99.6) |
| Gazeb | 77.6 (4.0) | 63.3 (7.7) | 85.4 (1.8) | 39.2 (8.4) | 94.0 (99.1) |
| Facial dynamics complexity | 75.9 (4.2) | 63.3 (6.5) | 82.9 (2.3) | 35.6 (7.3) | 93.8 (99.1) |
| Head movements | 86.4 (3.4) | 87.8 (4.1) | 74.4 (2.4) | 33.9 (6.8) | 97.6 (99.7) |
| Response to name | 65.8 (4.4) | 83.7 (5.1) | 46.6 (2.4) | 19.0 (3.2) | 95.0 (99.3) |
| Touch-based (game) | 57.6 (4.5) | 79.6 (5.2) | 39.0 (2.5) | 16.3 (2.7) | 92.8 (8.9) |
| All app variables + M-CHAT-R/F score | 96.6 (1.8) | 91.8 (4.5) | 92.1 (1.6) | 63.4 (19.7) | 98.7 (99.8) |
Results represent the performance of the XGBoost model trained to classify autistic and neurotypical groups based on individual and combined app variables (digital phenotypes).
aPPV and NPV values adjusted for population prevalence (Supplementary Table 1).
bGaze silhouette score, gaze speech correlation and gaze percent social.
AUROC, area under the ROC curve.