Child and maternal characteristics of participants (column percentage)
| Sociodemographics | n=6304 | n=549 | Pearson’s Chi-square P-value |
| Included n (%) | Excluded n (%) | ||
| Sex (at birth) | p=0.092 | ||
| Male | 3268 (51.8) | 264 (48.1) | |
| Female | 3036 (48.2) | 285 (51.9) | |
| Prioritised maternal ethnicity | p<0.001 | ||
| European | 3443 (54.8) | 143 (31.5) | |
| Māori | 848 (13.5) | 91 (20.0) | |
| Pacific | 866 (13.8) | 120 (26.4) | |
| Asian | 913 (14.5) | 79 (17.4) | |
| Others | 216 (3.4) | 21 (4.6) | |
| Maternal age in years | p<0.001 | ||
| <25 | 1174 (18.6) | 135 (29.6) | |
| 25 to 34 | 3523 (55.9) | 229 (50.2) | |
| >=35 | 1606 (25.5) | 92 (20.2) | |
| NZDep 2006 | p<0.001 | ||
| Low (<=3) | 1604 (25.5) | 80 (17.5) | |
| Medium (4-7) | 2341 (37.2) | 128 (28.1) | |
| High (8-10) | 2356 (37.4) | 248 (54.4) | |
| Injury occurrence recorded | p=0.746 | ||
| No | 5898 (93.6) | 158 (92.9) | |
| Yes | 406 (6.4) | 12 (7.1) | |