Table 4.
Rate ratios for developmental vulnerability according to the combination of Apgar scores at 1 and 5 min, singleton term live births, British Columbia, Canada
| 1 min Apgar | 5 min Apgar | Total number of children | Developmental vulnerability | |||
| No. with outcome (%) | Rate ratio (95% CI) | |||||
| Crude | Adjusted* | P for trend | ||||
| 7 | <7 | 20 | 9 (45.0) | 1.62 (0.99 to 2.65) | 1.34 (0.80 to 2.25) | |
| 7 | 7 | 172 | 56 (32.6) | 1.18 (0.93 to 1.48) | 1.18 (0.94 to 1.47) | |
| 7 | 8 | 1987 | 629 (31.7) | 1.14 (1.02 to 1.28) | 1.12 (1.01 to 1.23) | |
| 7 | 9 | 8700 | 2637 (30.3) | 1.09 (0.99 to 1.20) | 1.08 (0.99 to 1.19) | |
| 7 | 10 | 1140 | 317 (27.8) | 1.00 (reference) | 1.00 (reference) | 0.024 |
| 8 | <8 | 66 | 17 (25.8) | 0.85 (0.56 to 1.28) | 0.71 (0.47 to 1.07) | |
| 8 | 8 | 1337 | 420 (31.4) | 1.03 (0.94 to 1.13) | 1.01 (0.92 to 1.10) | |
| 8 | 9 | 33 255 | 10 007 (30.1) | 0.99 (0.94 to 1.04) | 0.97 (0.93 to 1.02) | |
| 8 | 10 | 4013 | 1222 (30.5) | 1.00 (reference) | 1.00 (reference) | 0.36 |
| 9 | <9 | 140 | 48 (34.3) | 1.17 (0.93 to 1.47) | 1.10 (0.88 to 1.38) | |
| 9 | 9 | 50 976 | 15 501 (30.4) | 1.03 (1.01 to 1.06) | 1.03 (1.01 to 1.05) | |
| 9 | 10 | 28 253 | 8303 (29.4) | 1.00 (reference) | 1.00 (reference) | 0.009 |
| 10 | <10 | 26 | 13 (50.0) | 1.68 (1.14 to 2.47) | 1.53 (1.08 to 2.17) | |
| 10 | 10 | 3057 | 911 (29.8) | 1.00 (reference) | 1.00 (reference) | 0.016† |
*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 (others vs English), birth order (2, 3, +4 vs 1), birth weight-for-gestational age (large, small vs appropriate) and gestational age (weeks).
†P value for difference in rates.
EDI, Early Development Instrument.