Table 2.
Background characteristics of the two samples in Chinaa.
| Sample | |||
|---|---|---|---|
| Pilot | Confirmatory | P b | |
| (n = 137) | (n = 567) | ||
| Mother and family | |||
| Mother age, years | 27.0 ± 2.9 | 24.6 ± 3.7 | <0.001 |
| Mother high school graduate % (n) | 66.2 (90/136) | 31.5 (174/552) | <0.001 |
| Annual household income % (n) | <0.001 | ||
| <5000, ¥ c | 46.5 (59/127) | 87.1 (481/552) | |
| >5000, ¥ | 53.5 (68/127) | 12.9 (71/552) | |
| Infant | |||
| Gender, %male (n) | 53.3 (73/137) | 54.5 (305/560) | 0.44 |
| Gestational age, weeks | 39.6 ± 0.9 | 39.7 ± 1.2 | 0.36 |
| Birth weight, g | 3420.1 ± 452.8 | 3375.6 ± 426.4 | 0.28 |
a n varies slightly due to occasional missing data for some measures. Values are expressed as means ± SD or % (n) for categorical variables.
b P values are based on t-tests for continuous variables and Fisher's exact analyses for categorical variables.
cYuan Renminbi, sign ¥, is the official currency of China. Approximate exchange rate 1$ = 6.31¥.