Baseline characteristics balance in the original ant matched cohort for each PS models
| Characteristics | Overall cohort (n=1195) | PS 1 matched cohort | PS 2 matched cohort | PS 3 matched cohort | ||
|---|---|---|---|---|---|---|
| No cricoid pressure (n=696) | Cricoid pressure (n=499) | SMD* | SMD* | SMD* | SMD* | |
| Age (mean, SD) | 63 (18) | 57 (18) | −0.33 | −0.02† | −0.15 | −0.22 |
| Gender (female) (n, %) | 245 (35) | 190 (38) | −0.06 | 0.09† | 0 | 0† |
| Obesity (n, %) | 97 (14) | 57 (11) | −0.08 | −0.03† | 0.03† | 0† |
| Operator’s status (senior) (n, %) | 318 (46) | 211 (42) | −0.07 | 0.04† | −0.07† | −0.09 |
| Patient's position‡(n, %) | 87 (12) | 280 (56) | 0.88 | 0† | 0† | 0† |
| Cervical immobilisation (n, %) | 55 (8) | 51 (10) | 0.08 | −0.04† | −0.02 | −0.10 |
| Reasons for intubation (n, %) | ||||||
| Cardiac arrest | 576 (83) | 89 (18) | −1.75 | 0† | 0† | −0.90 |
| Altered neurological status | 53 (8) | 295 (59) | 1.05 | −0.05† | 0† | 0.73 |
| Acute respiratory distress | 22 (3) | 32 (6) | 0.13 | −0.02† | −0.02† | −0.15 |
| Shock | 29 (4) | 83 (17) | 0.33 | 0.09† | 0.01† | 0.05 |
| Weighted balance measure | ||||||
| Overall cohort (n=1195) | PS 1 matched cohort | PS 2 matched cohort | PS 3 matched cohort | |||
| 29.70 | 1.48 | 0.41 | 15.58 | |||
*SMD is the mean difference divided by the pooled SD.
†Variables included in each PS model.
‡Stretcher at full height.
PS, propensity score; SMD, standardised mean difference.