Unadjusted rates (%) of adverse outcomes on high-volume versus low/average-volume days, stratified by weekday/weekend
| Overall | Weekday | Weekend | p Value | Weekday | Weekend | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| Low/average-volume day | High-volume day | p Value | Low/average-volume day | High-volume day | p Value | |||||
| Maternal | ||||||||||
| Obstetric infection | 3.1 | 3.0 | 3.4 | <0.001 | 3.0 | 2.9 | 0.037 | 3.3 | 3.9 | <0.001 |
| Haemorrhage | 3.7 | 3.7 | 3.9 | <0.001 | 3.8 | 3.5 | <0.001 | 3.8 | 4.3 | 0.001 |
| Severe perineal laceration | 2.4 | 2.4 | 2.6 | <0.001 | 2.4 | 2.3 | 0.304 | 2.7 | 2.5 | 0.119 |
| Prolonged LOS* | 3.7 | 3.5 | 4.2 | <0.001 | 3.5 | 3.5 | 0.161 | 4.1 | 4.7 | <0.001 |
| Composite maternal | 11.3 | 11.0 | 12.4 | <0.001 | 11.1 | 10.8 | 0.010 | 12.3 | 13.2 | <0.001 |
| Neonatal | ||||||||||
| Birth trauma | 3.5 | 3.5 | 3.5 | 0.539 | 3.5 | 3.5 | 0.403 | 3.5 | 3.5 | 0.624 |
| Neonatal seizures | 0.1 | 0.1 | 0.1 | 0.830 | 0.1 | 0.1 | 0.074 | 0.1 | 0.1 | 0.821 |
| Apgar score <7 | 0.7 | 0.6 | 0.8 | <0.001 | 0.6 | 0.6 | 0.927 | 0.7 | 0.9 | 0.012 |
| NICU admission | 4.2 | 4.1 | 4.5 | <0.001 | 4.2 | 4.1 | 0.026 | 4.5 | 4.8 | 0.047 |
| Neonatal death | 0.2 | 0.1 | 0.2 | 0.339 | 0.2 | 0.1 | 0.141 | 0.2 | 0.1 | 0.156 |
| Composite infant | 7.9 | 7.8 | 8.2 | <0.001 | 7.9 | 7.7 | 0.011 | 8.1 | 8.5 | 0.075 |
Bold typeface indicates p<0.05.
*Prolonged LOS defined as LOS >3 days for vaginal deliveries and >5 days for caesarean deliveries.
LOS, length of stay; NICU, neonatal intensive care unit.