Table 1.
Sociodemographic characteristics of the sample according to feeding status (1 month)
| Variables | Excl. Breastfeeding | Mixed Feeding | Excl. Formula Feeding | F (df) / X2(df) | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| N | % | Mean (SD) | N | % | Mean (SD) | N | % | Mean (SD) | ||
| Mother and Partner’s characteristics | ||||||||||
| Mother’s Age | 4772 | – | 29.46A (4.49) | 1861 | – | 28.95B (4.58) | 4463 | – | 26.73C (4.85) | 420.75 (2)** |
| Primipara (Y) | 4617 | 42.7A | – | 1791 | 46.5B | – | 4183 | 39.7C | – | 18.55 (2)** |
| Self-reported smoking in pregnancy (Y) | 4686 | 15.8A | – | 1825 | 21.0B | – | 4268 | 31.1C | – | 109.92 (2)** |
| Self-reported partner’s daily cigarette consumption | 4242 | – | 3.06A (7.09) | 1617 | – | 4.02B (8.08) | 3476 | – | 5.25C (8.47) | 75.13 (2)** |
| Mother’s Education | 4487A | – | 1721B | – | 3789C | – | 1203.61 (8)** | |||
| CSE | 7.9 | 9.5 | 22.6 | |||||||
| Vocational | 6.9 | 8.5 | 14.6 | |||||||
| O-Level | 32.6 | 37.7 | 42.5 | |||||||
| A-Level | 29.9 | 28.8 | 16.3 | |||||||
| University Degree | 22.7 | 15.6 | 3.9 | |||||||
| Partner’s Education | 4256A | – | 1623B | – | 3398C | – | 830.94 (8)** | |||
| CSE | 10.9 | 14.7 | 25.6 | |||||||
| Vocational | 7.2 | 8.6 | 12.2 | |||||||
| O-Level | 21.1 | 23.8 | 26.4 | |||||||
| A-Level | 29.4 | 32.5 | 28 | |||||||
| University Degree | 31.4 | 20.3 | 7.9 | |||||||
| Crowding Index | 4580A | – | 1795A | – | 4163B | – | 345.88 (6)** | |||
| ≤ 0,5 person per room | 49 | 49.1 | 33.7 | |||||||
| > 0,5–0,75 person per room | 30.9 | 32.2 | 32.8 | |||||||
| > 0,75–1 person per room | 16 | 14 | 25 | |||||||
| > 1 person per room | 4.1 | 4.7 | 8.6 | |||||||
| HOME Score | 4363 | – | 10.41A (1.55) | 1643 | – | 10.37A (1.59) | 3661 | – | 10.13B (1.64) | 30.80 (2)** |
| Maternal return to work (Y) | 4432 | 34.3A | – | 1695 | 40B | – | 3789 | 28.8C | – | 70.71 (2)** |
| Self-reported maternal smoking since birth (Y) | 4594 | 14.3A | – | 1778 | 19.3B | – | 4057 | 31.3C | – | 370.46 (2)** |
| Maternal depressive symptoms (32 gestational weeks) | 4503 | – | 6.47A (4.81) | 1740 | – | 6.68A (4.91) | 4008 | – | 7.45B (5.16) | 42.80 (2)** |
| Maternal depressive symptoms (8 weeks postpartum) | 4590 | – | 5.61A (4.40) | 1776 | – | 6.08B (4.80) | 4054 | – | 6.30C (4.98) | 23.64 (2)** |
| Infant characteristics | ||||||||||
| Baby’s sex (M) | 4772 | 50.2A | – | 1861 | 53.1B | – | 4463 | 52.6C | – | 7.08 (2)* |
| Baby’s Birthweight | 4772 | – | 3498.61A (445.40) | 1861 | – | 3488.09A (465.16) | 4463 | – | 3461.16B (469.63) | 7.88 (2)** |
| Gestational Age | 4772 | – | 39.67A (1.39) | 1861 | – | 39.67A (1.44) | 4463 | – | 39.66A (1.48) | 0.89 (2) |
| IQ (Total – 4y) | 440 | – | 107.05A (14.46) | 181 | – | 106.73A (12.68) | 298 | – | 100.53B (13.58) | 21.70 (2) ** |
| IQ (Total - 8y) | 3052 | – | 107.47A (16.16) | 1134 | – | 105.61B (16.21) | 1989 | – | 99.98C (15.58) | 134.25 (2) ** |
| Hyperactivity (SDQ – 4y) | 3786 | – | 3.62A (2.28) | 1393 | – | 3.94B (2.26) | 3037 | – | 4.29C (2.31) | 72.07 (2)** |
| Emotional Symptoms (SDQ – 4y) | 3821 | – | 1.40A (1.49) | 1412 | – | 1.45A (1.49) | 3060 | – | 1.46A (1.50) | 0.24 (2) |
| Conduct Problems (SDQ – 4y) | 3816 | – | 1.84A (1.36) | 1408 | – | 1.98B (1.48) | 3064 | – | 2.02C (1.41) | 14.61 (2)** |
| Total Behavior Score (SDQ – 4y) | 3718 | – | 8.27A (4.40) | 1370 | – | 8.85B (4.50) | 2970 | – | 9.37C (4.61) | 48.95 (2)** |
| Hyperactivity (SDQ – 9y) | 3273 | – | 2.71A (2.12) | 1229 | – | 3.01B (2.34) | 2336 | – | 3.05C (2.22) | 20.96 (2)** |
| Emotional Symptoms (SDQ - 9y) | 3269 | – | 1.44A (1.63) | 1224 | – | 1.51A (1.72) | 2338 | – | 1.58A (1.79) | 1.75 (2) |
| Conduct Problems (SDQ – 9y) | 3279 | – | 1.21A (1.34) | 1224 | – | 1.26A (1.31) | 2339 | – | 1.33B (1.41) | 4.33 (2)** |
| Total Behavior Score (SDQ – 9y) | 3245 | – | 6.41A (4.65) | 1219 | – | 6.90B (4.81) | 2318 | – | 7.02C (5.01) | 12.99 (2)** |
Note: SD standard deviation, F F statistic, df degrees of freedom, X2 chi-square, M male, m months, Y yes, y years, IQ Intelligence Quotient, SDQ Strengths and Difficulties Questionnaire, A-B-C groups not sharing the same superscript are different from each other at p <.05; **Significant at the p =.01 level; *Significant at the p =.05 level