Distribution of missing data for cases of severe maternal morbidity and controls
| Variable | Number of cases with missing information (% of total cases) | Number of controls with missing information (% of total controls) |
|---|---|---|
| Socioeconomic group | 193 (16.9) | 303 (13.4) |
| Ethnicity | 18 (1.6) | 78 (3.5) |
| Age | 3 (0.3) | 18 (0.8) |
| Smoking | 28 (2.5) | 61 (2.7) |
| Pre-existing medical condition(s) | 6 (0.5) | 27 (1.2) |
| Body mass index | 128 (11.2) | 219 (9.7) |
| Parity | 3 (0.3) | 22 (1.0) |
| Multiple pregnancy | 2 (0.2) | 18 (0.8) |
| Past pregnancy complication(s) | 9 (0.8) | 31 (1.4) |