National Congenital Anomaly System (NCAS) fields with unknown and blank responses over the last five years (1998–2002)
| Key fields in the NCAS database | Unknown/blank entries |
|---|---|
| Data shown as at end of July 2003. Values in parentheses are percentages. | |
| Date of last menstrual period | 25767 (72.0) |
| Parents’ occupation (father) | 20603 (57.6) |
| Parents’ occupation (mother) | 18915 (52.9) |
| Estimated gestation | 8598 (24.0) |
| Place of birth of child | 6559 (18.3) |
| Birth weight of baby | 5675 (15.9) |
| Mother’s date of birth | 1576 (4.4) |
| Sex of child | 196 (0.5) |
| Live or still birth | 94 (0.3) |