Table 2 Sample Characteristics
Children participating in the OX-NDA evaluation study (n = 104) Mean (SD) or number (%) | Children in the Pelotas 2015 Birth Cohort not participating in the OX-NDA evaluation study (n = 3914) Mean (SD) or number (%) | p value | |
|---|---|---|---|
Socio-demographic, prenatal and perinatal characteristics | |||
Maternal age at recruitment, years | 27.1 (6.6) | 27.5 (6.2) | 0.51 |
Monthly family income | 3585.6 (5667.7) | 3010.9 (4377.3) | 0.55 |
Duration of mother’s formal education, years | 10.1 (4.0) | 10.7 (4.0) | 0.09 |
Maternal employment status | 49 (47.1%) | 1878 (47.9%) | 0.06 |
Maternal infections (including HIV, rubella, syphilis, hepatitis B, CMV, toxoplasmosis, tuberculosis and malaria) | 10.0 (11.6%) | 348 (9.6%) | 0.49 |
Maternal substance abuse (including alcohol) and smoking | 20 (19.2%) | 582 (16.1%) | 0.18 |
Maternal prenatal anxiety and depression/mental stress | 15 (14.4%) | 402 (11.1%) | 0.26 |
Maternal preeclampsia and eclampsia | 10 (9.6%) | 227 (6.3%) | 0.10 |
Perinatal and Neonatal characteristics | |||
Gestational age at delivery, weeks | 38.7 (2.0) | 38.4 (2.4) | 0.34 |
Birth weight, kg | 3.2 (0.5) | 3.2 (0.5) | 0.39 |
Birth length, cm | 48.3 (2.6) | 40.2 (3.2) | 0.64 |
Head circumference at birth, cm | 33.9 (1.5) | 33.9 (2.9) | 0.94 |
Apgar score at 5 min | 9.5 (0.6) | 9.7 (4.3) | 0.13 |
Boys | 55 (53.0%) | 1848 (51.1%) | 0.72 |
Postnatal characteristics | |||
Only child | 51 (49.0%) | 1905 (48.7%) | 0.95 |
Mean age of 12-month / OX-NDA assessment (days) | 367.6 (8.4) | – | – |
Significant morbidity during the first year of life1 | 4 (3.8%) | 153 (5.1%) | 0.73 |
Weight at 1 year, kg | 10.1 (1.2) | 9.9 (1.4) | 0.28 |
Length at 1 year, cm | 75.1 (3.1) | 75.0 (3.0) | 0.63 |
Immunized for age | 90 (100%) | 2955 (99.7%) | 0.60 |
Age at which infant was weaned, months | 5.7 (3.4) | 4.1 (3.8) | *0.001 |
BSID-III assessment conducted before OX-NDA | 52 (50%) | – | – |
Duration between OX-NDA and BSID-III assessments at 1 year, day | 1 (0) | – | – |