| AHA | American Hospital Association |
| ANOVA | Analysis of variance |
| O-E | Observed-to-expected |
| OB | Obstetric |
| OBLEV | Obstetric level of care |
| US | United States of America |
| AHA | American Hospital Association |
| ANOVA | Analysis of variance |
| O-E | Observed-to-expected |
| OB | Obstetric |
| OBLEV | Obstetric level of care |
| US | United States of America |