Table 4.
Measurement | Control | Intervention | Difference between groups | Effect size | ||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
n | Mean | Median | n | Mean | Median | Mean | Median | p-valuea | Cohen’s db | 95% CI | ||
Birth weight (overall, grams) | 12 | 2913.3 | 2877.5 | 32 | 3234.7 | 3115.0 | 321.4 | 237.5 | 0.03 | 0.65 | − 0.04 | 1.32 |
Males (grams)^ | 7 | 3070.7 | 3000 | 13 | 3145.8 | 3035 | 75.1 | 35.0 | 0.86 | 0.20 | − 0.72 | 1.12 |
Females (grams)^ | 4 | 2783.8 | 2767.5 | 12 | 3362.5 | 3370 | 578.7 | 602.5 | 0.03 | 0.89 | − 0.31 | 2.05 |
Gestational age (overall, weeks) | 12 | 38.2 | 38.0 | 32 | 39.7 | 40.0 | 1.5 | 2.0 | 0.01 | 1.05 | 0.34 | 1.74 |
Males (weeks)^ | 7 | 38.6 | 38.0 | 13 | 39.7 | 40.0 | 1.1 | 2.0 | 0.26 | 0.64 | − 0.31 | 1.58 |
Females (weeks)^ | 4 | 38.0 | 38.0 | 12 | 39.7 | 40.0 | 1.7 | 2.0 | 0.10 | 1.21 | − 0.03 | 2.40 |
Weight-for-gestational age (z-score)^& | 11 | − 0.45 | − 0.51 | 25 | − 0.16 | − 0.06 | 0.29 | 0.45 | 0.38 | 0.24 | − 0.47 | 0.95 |
Males (z-score)^ | 7 | − 0.34 | − 0.26 | 13 | − 0.51 | − 0.26 | − 0.17 | 0.0 | 0.66 | − 0.21 | − 1.13 | 0.72 |
Females (z-score)^ | 4 | − 0.64 | − 0.58 | 12 | 0.22 | 0.21 | 0.86 | 0.79 | 0.10 | 0.59 | − 0.57 | 1.74 |
APGAR 1 min | 12 | 8.8 | 9.0 | 28 | 8.7 | 9.0 | − 0.1 | 0.0 | 0.61 | − 0.31 | − 0.98 | 0.38 |
Males^ | 7 | 9.0 | 9.0 | 10 | 9.0 | 9.0 | 0 | 0 | 0.99 | – | – | – |
Females^ | 4 | 8.5 | 8.5 | 11 | 8.6 | 9.0 | 0.1 | 0.5 | 0.99 | 0.26 | − 0.89 | 1.40 |
APGAR 5 min | 12 | 9.8 | 10.0 | 28 | 9.6 | 10.0 | − 0.2 | 0.0 | 0.82 | − 0.20 | − 0.88 | 0.48 |
Males^ | 7 | 9.9 | 10.0 | 10 | 10.0 | 10.0 | 0.1 | 0 | 0.82 | 0.60 | − 0.40 | 1.58 |
Females^ | 4 | 9.5 | 9.5 | 11 | 9.5 | 10.0 | 0 | 0.5 | 0.99 | 0.08 | − 1.06 | 1.23 |
Data presented are on singletons only (i.e., two sets of twins were excluded from these analyses). Additional overall infant characteristics are presented in Additional file 1
ap-values are based on Wilcoxon rank-sum test using exact probabilities (instead of normal approximation)
bCalculated using groups’ means from a single time point (i.e., at birth)
^Among singletons with documented sex
&Sex and birthweight standardized z-scores determined from study biometry using INTERGROWTH-21st standards, accessed 8 May 2022 from URL: http://intergrowth21.ndog.ox.ac.uk/