Apgar scores at 1 and 5 min and rate ratios for developmental vulnerability among singleton term live births, British Columbia, Canada
| Apgar score | Total number of children | Developmental vulnerability | ||
| No. with outcome (%) | Rate ratio (95% CI) | |||
| Crude | Adjusted* | |||
| 1 min Apgar | 150 081 | 45 334 (30.2) | ||
| 0 | 24 | 9 (37.5) | 1.25 (0.74 to 2.10) | 1.08 (0.64 to 1.83) |
| 1 | 469 | 161 (34.3) | 1.15 (1.00 to 1.31) | 1.16 (1.02 to 1.32) |
| 2 | 1060 | 329 (31.0) | 1.04 (0.93 to 1.15) | 1.03 (0.93 to 1.14) |
| 3 | 1760 | 546 (31.0) | 1.04 (0.95 to 1.13) | 1.03 (0.95 to 1.13) |
| 4 | 2582 | 814 (31.5) | 1.05 (0.97 to 1.14) | 1.07 (0.99 to 1.15) |
| 5 | 4069 | 1261 (31.0) | 1.03 (0.96 to 1.11) | 1.05 (0.98 to 1.12) |
| 6 | 6975 | 2124 (30.5) | 1.02 (0.95 to 1.08) | 1.04 (0.98 to 1.11) |
| 7 | 12 019 | 3648 (30.4) | 1.01 (0.95 to 1.08) | 1.03 (0.97 to 1.09) |
| 8 | 38 671 | 11 666 (30.2) | 1.01 (0.95 to 1.06) | 1.02 (0.96 to 1.08) |
| 9 | 79 369 | 23 852 (30.1) | 1.00 (0.95 to 1.06) | 1.00 (0.95 to 1.06) |
| 10 | 3083 | 924 (30.0) | 1.00 (reference) | 1.00 (reference) |
| P for trend | <0.001 | |||
| Per one unit of Apgar | 0.99 (0.98 to 0.99) | |||
| 5 min Apgar | ||||
| 0 | 20 | 7 (35.0) | 1.18 (0.65 to 2.15) | 1.16 (0.62 to 2.17) |
| 1 | 16 | 9 (56.3) | 1.90 (1.24 to 2.93) | 1.88 (1.27 to 2.77) |
| 2 | 28 | 13 (46.4) | 1.57 (1.05 to 2.34) | 1.57 (1.03 to 2.39) |
| 3 | 83 | 30 (36.2) | 1.22 (0.92 to 1.63) | 1.25 (0.93 to 1.67) |
| 4 | 106 | 43 (40.6) | 1.37 (1.09 to 1.73) | 1.33 (1.06 to 1.67) |
| 5 | 290 | 85 (29.3) | 0.99 (0.83 to 1.19) | 0.98 (0.82 to 1.17) |
| 6 | 932 | 306 (32.8) | 1.11 (1.01 to 1.22) | 1.08 (0.99 to 1.18) |
| 7 | 2375 | 740 (31.2) | 1.05 (0.99 to 1.12) | 1.08 (1.01 to 1.14) |
| 8 | 7666 | 2387 (31.1) | 1.05 (1.02 to 1.09) | 1.06 (1.02 to 1.10) |
| 9 | 101 191 | 30 668 (30.3) | 1.03 (1.01 to 1.04) | 1.02 (1.00 to 1.04) |
| 10 | 37 374 | 11 046 (29.6) | 1.00 (reference) | 1.00 (reference) |
| P for trend | <0.001 | |||
| Per one unit of Apgar | 0.98 (0.97 to 0.99) | |||
*Adjusted for child’s sex (male vs female), child’s age at EDI completion (years), socioeconomic status (first quintile, second quintile, third quintile, fourth quintile vs fifth quintile), child’s first language (other vs English), birth order (2, 3, +4 vs 1), birth weight-for-gestational age (large, small vs appropriate) and gestational age (weeks).
EDI, Early Development Instrument.