Results of exhaled hydrogen sulfide (H2S) ROC curve analysis
| Sensitivity (95% CI) | Specificity (95% CI) | Likelihood ratio | |
| Oral H2S>16.4 | 0.91 (0.80 to 0.97) | 0.33 (0.23 to 0.45) | 1.36 |
| Oral H2S>54.3 | 0.42 (0.28 to 0.56) | 0.90 (0.81 to 0.95) | 4.08 |
| Nasal H2S>6.85 | 0.91 (0.80 to 0.97) | 0.23 (0.15 to 0.36) | 1.19 |
| Nasal H2S>16.6 | 0.36 (0.23 to 0.50) | 0.90 (0.81 to 0.96) | 3.64 |