Table 3.
Effect estimates of the ROX index for predicting the successful weaning from HFNC
| Variables | Grouping | No. of studies | No. of subjects | AUHSROC | Sensitivity (%) | Specificity (%) | Diagnostic odds ratio | Estimated optimal cutoff value | ||
|---|---|---|---|---|---|---|---|---|---|---|
| HFNC success | HFNC failure | Mean value (95% CI) | Median value (95% CI) | |||||||
| Primary analysis | All studies | 13 | 1003 | 748 | 0.81 (0.77, 0.84) | 0.71 (0.64, 0.78) | 0.78 (0.70, 0.84) | 8.3 (6.4, 10.8) | 4.8 (4.2, 5.4) | 5.3 (4.2, 5.5) |
| Subgroup analyses | ||||||||||
| Measurement time point | Within 6 h after HFNC onset | 10 | 757 | 640 | 0.80 (0.76, 0.83) | 0.66 (0.56, 0.75) | 0.79 (0.72, 0.84) | 7.3 (5.6, 9.4) | 5.0 (4.2, 5.8) | 5.3 (4.0, 5.8) |
| During 6–12 h after HFNC onset | 7 | 570 | 327 | 0.84 (0.81, 0.87) | 0.77 (0.64, 0.85) | 0.80 (0.61, 0.91) | 11.5 (6.4, 20.7) | 5.0 (4.2, 5.9) | 5.3 (3.9, 5.9) | |
| Pneumonia type | COVID-19 | 10 | 757 | 640 | 0.79 (0.75, 0.82) | 0.67 (0.61, 0.73) | 0.82 (0.74, 0.88) | 8.7 (6.4, 11.8) | 4.9 (4.2, 5.6) | 5.3 (4.2, 5.5) |
| Non-COVID-19 | 3 | 246 | 108 | NE | NE | NE | NE | NE | NE | |
| Study design | Prospective | 6 | 435 | 327 | 0.79 (0.75, 0.82) | 080 (0.68, 0.88) | 0.70 (0.62, 0.77) | 8.6 (5.4, 13.5) | 4.3 (3.0, 5.6) | 4.3 (2.8, 5.7) |
| Retrospective | 7 | 568 | 421 | 0.75 (0.71, 0.78) | 0.65 (0.59, 0.71) | 0.86 (0.74, 0.93) | 8.4 (5.8, 12.1) | 5.3 (4.9, 5.7) | 5.4 (4.8, 5.8) | |
| Sensitivity analysis | Excluding studies without explicit AHRF definition | 8 | 682 | 519 | 0.80 (0.76, 0.83) | 0.75 (0.64, 0.84) | 0.73 (0.66, 0.80) | 7.6 (5.7, 10.0) | 4.7 (3.8, 5.6) | 5.1 (3.2, 5.6) |
HFNC high-flow nasal cannula, COVID-19 coronavirus disease 2019, AHRF acute hypoxemic respiratory failure, NE not estimable, CI confidential interval