Performance measures from 12 runs of random sets
| Specificity (%) | Sensitivity | NPV (%) | PPV | Accuracy | |||
| Non-COVID-19 pneumonia (%) | COVID-19 pneumonia (%) | Non-COVID-19 pneumonia (%) | COVID-19 pneumonia (%) | ||||
| Test group# | |||||||
| With IFS | 93±4** | 70±7 | 97±2** | 90±4** | 90±4* | 94±3** | 92±1** |
| No IFS | 80±7 | 69±11 | 93±4 | 85±5 | 84±6 | 85±3 | 85±2 |
| Cross-validation¶ | |||||||
| With IFS | 87±2** | 71±7* | 93±2** | 88±3* | 78±6** | 89±1** | 87±2** |
| No IFS | 75±4 | 65±8 | 85±3 | 79±2 | 68±5 | 80±2 | 78±2 |
| Auscultation by acoustic stethoscope (95% CI)+ | 76 (68–83) | 72 (59–82) | 25 (17–32) | 43 (37–50) | 71 (62–79) | 52 (44–66) | |
VoqX data are presented as mean±sd. IFS: infrasound; NPV: negative predictive value; PPV: positive predictive value. #: not in the learning process; ¶: optimisation of the learning process; +: all data. *: p<0.05; **: p<0.01 versus no IFS.