Rate ratios* (RR) of cerebral palsy by Z-score band for more severe cases only
| Z-score band | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| <−1.88 RR (n) | −1.88 to <−1.28 RR (n) | −1.28 to <−0.67 RR (n) | −0.67 to <0 RR (n) | 0 to <0.67 RR (n) | 0.67 to <1.28 RR (n) | 1.28 to <1.88 RR (n) | ⩾1.88 RR (n) | Total more severe n† | Total mild n | Denominator (estimated)§ | |
| *Rate ratio by comparison to reference band 0.67 to <1.28 Z-score. Bold, p < 0.01. Rates can be calculated for each cell by allocating the denominator column to the percentages in the final table row (i.e. assuming a Normal denominator distribution). Rate ratios are between Z-score bands and are not reliant on exact denominator allocation to row subsets. | |||||||||||
| †Cases include only those with values for severity (e.g. “All gestations” row includes 3122 of 3258 non-German cases—see Results para 1). | |||||||||||
| ‡For gestation or sex specific rates the overall denominator is split 94.25% term or 51.3% male: as observed in SCPE centres providing denominator detail. | |||||||||||
| §There were 1 693 311 live births during case birth years in the catchments of those registers with cases in the main analyses. When extra registers and year groups with sufficient case data for sub-analysis by walking ability are included the denominator rises to 2 358 379 (see Results para 1). | |||||||||||
| All gestations | 13.4 (271) | 4.6 (215) | 2.7 (268) | 1.7 (278) | 1.3 (225) | 1 (101) | 1.4 (66) | 3.3 (66) | 1490 | 1632 | 1693311 |
| Term‡ | 16.5 (135) | 4.6 (88) | 2.7 (109) | 1.9 (130) | 1.4 (93) | 1 (41) | 1.5 (28) | 4.0 (33) | 657 | 608 | 1601675 |
| Preterm | 11.3 (136) | 4.5 (127) | 2.7 (159) | 1.5 (148) | 1.3 (132) | 1 (60) | 1.4 (38) | 2.8 (33) | 833 | 1024 | 91635 |
| Bilat spastic | 15.1 (253) | 4.5 (178) | 2.8 (233) | 1.7 (237) | 1.3 (176) | 1 (84) | 1.3 (51) | 3.0 (50) | 1262 | 688 | |
| Hemiplegia | 12.5 (15) | 6.8 (19) | 2.8 (17) | 1.9 (19) | 1.6 (16) | 1 (6) | 1.8 (5) | 2.5 (3) | 100 | 861 | |
| Males‡ | 16.4 (164) | 5.5 (128) | 3.1 (153) | 1.8 (152) | 1.6 (130) | 1 (50) | 1.3 (30) | 3.7 (37) | 844 | 959 | 868668 |
| Females | 10.5 (107) | 3.7 (87) | 2.3 (115) | 1.5 (126) | 1.1 (95) | 1 (51) | 1.5 (36) | 2.8 (29) | 646 | 673 | 824642 |
| Intellectual impairment (IQ <50) | |||||||||||
| All gestations | 14.1 (169) | 5.0 (141) | 2.8 (168) | 1.5 (154) | 1.3 (129) | 1 (60) | 1.4 (39) | 2.8 (34) | 894 | 2272 | 1713217 |
| Walking impairment (not walking independently) | |||||||||||
| All gestations | 12.6 (355) | 3.6 (239) | 2.3 (326) | 1.5 (354) | 1.3 (296) | 1 (141) | 1.4 (93) | 3.3 (93) | 1897 | 2286 | 2358379 |
| Equivalent centiles | <3% | 3 to <10% | 10 to <25% | 25 to <50% | 50 to <75% | 75 to <90% | 90 to <97% | ⩾97% | 100% | ||
| % of births | 3 | 7 | 15 | 25 | 25 | 15 | 7 | 3 | |||