Table 2.
Descriptive Statistics of Study Sample
| Variable | n | N (%) | Mean (CI 95%) | Correlationsa, p-value | ANOVA t-test | RR (CI 95%) univariate |
|---|---|---|---|---|---|---|
| Child BMI at 6 years | 231 | n.a. | 16.36 (16.06–16.67) | n.a. | n.a. | n.a. |
| Obesity status at 6 years | ||||||
| Normal weight | 156 | (67.5) | n.a. | n.a. | n.a. | n.a. |
| Overweight | 35 | (15.2) | n.a. | n.a. | n.a. | n.a. |
| Obese | 40 | (17.3) | n.a. | n.a. | n.a. | n.a. |
| EBF (weeks)b | 324 | n.a. | 7.56 (6.55–8.58) | −0.16, 0.01 | n.a. | −0.04 (−0.07 to −0.01) |
| FBF (weeks)b | 324 | n.a. | 11.64 (10.45–12.84) | −0.17, <0.01 | n.a. | −0.04 (−0.06 to −0.01) |
| ABF (weeks) | 323 | n.a. | 27.96 (25.45–30.46) | 0.02, 0.76 | n.a. | |
| Sex of child | 324 | 0.24 | ||||
| Male | 177 (54.7) | n.a. | n.a. | n.a. | ||
| Female | 147 (45.3) | n.a. | n.a. | n.a. | ||
| Birth weight (g) | 324 | n.a. | 3270 (3230–3320) | 0.10, 0.14 | n.a. | n.a. |
| Weight gain first year (kg)b | 287 | n.a. | 6.86 (6.71–7.01) | 0.26, 0.01 | n.a. | 0.48 (0.24–0.72) |
| Maternal origin | 324 | 0.52 | ||||
| Native born | 262 (81) | n.a. | n.a. | n.a. | ||
| Foreign born | 62 (19) | n.a. | n.a. | n.a. | ||
| Maternal age (y) | 324 | n.a. | 31.57 (31.00–32.14) | −0.06, 0.34 | n.a. | n.a. |
| Maternal Pre-Gestational BMIb | 219 | n.a. | 24.59 (23.96–25.23) | 0.26, <0.01 | n.a. | 0.48 (0.24–0.72) |
| Maternal smoking | ||||||
| Periconceptionalb | 324 | |||||
| Smoking | 204 (63.0) | n.a. | n.a. | 0.03 | 0.69 (0.06–1.32) | |
| Not Smoking | 120 (37.0) | n.a. | n.a. | n.a. | n.a. | |
| Cigarettes/week | n.a. | 27.90 (22.66–33.13) | 0.20, <0.01 | n.a. | 0.01 (0.00–0.02) | |
| Postnatal (1 year)b | 323 | |||||
| Smoking | 84 (26.0) | n.a. | n.a. | 0.01 | 0.88 (0.19–1.58) | |
| Not smoking | 239 (74.0) | n.a. | n.a. | n.a. | n.a. | |
| Cigarettes/week | n.a. | 12.79 (9.55–16.04) | −0.06, 0.67 | n.a. | n.a. | |
| Maternal alcohol intake (Pregnancy)b | 324 | 0.16 | ||||
| Yes | 37 (11.4) | 5.09 (3.24–6.94) | n.a. | n.a. | ||
| No | 287 (88.6) | n.a. | n.a. | |||
| Alcohol (Grams/Day) | n.a. | 0.23, <0.01 | 0.21 (0.09–0.32) | |||
| Maternal Occupation | 324 | 0,15 | ||||
| outside the home | 158 (48.9) | n.a. | n.a. | n.a. | ||
| at home | 165 (51.1) | n.a. | n.a. | n.a. | ||
| Education level: Motherb | 324 | 70 (21.6) | n.a. | −0.17, 0.01 | 0.05 | Ref |
| None/Primary | 154 (47.5) | n.a. | −0.13 (−0.93 to | |||
| Secondary | n.a. | 0.67) | ||||
| University | 100 (30.9) | −0.86 (−1.75 to −0.02) | ||||
| Education level: Fatherb | 324 | −0.19, <0.01 | 0.04 | |||
| None/primary | 93 (29.8) | n.a. | Ref | |||
| Secondary | 144 (46.2) | n.a. | −0.37 (−1.01 to 0.34) | |||
| University | 75 (24.0) | n.a. | −1.08 (−1.96 to −0.24) | |||
| Family net income (€/month)b | 323 | −0.26, <0.01 | <0.01 | |||
| <800 | 38 (11.8) | n.a. | 1.64 (0.46–2.81) | |||
| 800–1499 | 124 (38.4) | n.a. | 1.31 (0.50–2.13) | |||
| 1500–2500 | 93 (28.8) | n.a. | 0.61 (−0.22 to 1.44) | |||
| >2500 | 68 (21.1) | n.a. | Ref | |||
a
Correlation Pearson coefficient between “Child BMI at 6 years” and the correspondent variable.
b
p < 0.05 for excess weight and obesity at 6 years old in univariate analysis. Ref = Category used as reference for RR. Univariate statistics used include Chi-Squared tests, Pearson's Correlation, Spearman's Correlation, ANOVA, t-test to obtain predictor variables.
ABF, any breastfeeding; EBF, exclusive breastfeeding; FBF, full breastfeeding; n.a., not applicable; RR, relative risk.