Table 1 Summary statistics
From: Analysis of neonatal mortality:is standardizing for relative birth weight biased?
| Blacks | Whites | Total | ||
|---|---|---|---|---|
| Birth weight(grams) | N | 3,683,572 | 18,409,287 | 22,092,859 |
| Mean | 3125 | 3395 | 3345 | |
| SD | 633 | 572 | 591 | |
| Estimated optimal birth weight (grams)* | 3550 | 4150 | 3950 | |
| Gestational age (weeks) | Mean | 38.5 | 39.2 | 39.0 |
| SD | 3.0 | 2.3 | 2.5 | |
| Percent | <32 weeks | 3.4 | 1.1 | 1.5 |
| <34 weeks | 5.9 | 2.2 | 2.8 | |
| <37 weeks | 17.0 | 8.8 | 10.1 | |
| Percent | <1500 g | 2.6 | 0.9 | 1.1 |
| <2500 g | 12.4 | 5.5 | 6.7 |