Table 3.
Comparative efficacy of the four tests
| Parameters | Value as per | |||
|---|---|---|---|---|
| MMT (%) | TMD test (%) | SMD test (%) | TMHT (%) | |
| True positive | 17 | 7 | 6 | 24 |
| False positive | 59 | 5 | 8 | 9 |
| True negative | 254 (73) | 308 (89) | 305 (88) | 304 (88) |
| False negative | 15 | 25 | 26 | 8 |
| Sensitivity | 53 | 22 | 19 | 75 |
| Specificity | 81 | 98 | 97 | 97 |
| Positive predictive value | 22 | 58 | 43 | 73 |
| Negative predictive value | 94 | 92 | 92 | 97 |
| Accuracy | 79 | 91 | 90 | 95 |
True positive: A difficult laryngoscopy that had been predicted to be difficult. False positive: An easy laryngoscopy that had been predicted to be difficult. True negative: An easy laryngoscopy that had been predicted to be easy. False negative: A difficult laryngoscopy that had been predicted to be easy. MMT: Modified Mallampati test, TMD: Thyromental distance, SMD: Sternomental distance, TMHT: Thyromental height test