Prevalence of colic (%) and odds ratios (OR) for colic regarding age of the infant, maternal smoking behaviour, and type of feeding
| Categories | No.1-150 | % | Unadjusted OR | p value | Adjusted OR1-151 | p value1-152 |
|---|---|---|---|---|---|---|
| Age of infant1-153 | 0.000 | |||||
| 1 month | 1115 | 9.0 | 1.00 | — | ||
| 3 months | 1085 | 3.7 | 0.39 (0.27 to 0.57) | |||
| 6 months | 1120 | 1.3 | 0.14 (0.08 to 0.24) | |||
| Maternal smoking | 0.046 | 0.015 | ||||
| Never | 2588 | 4.3 | 1.00 | 1.00 | ||
| <15 cigarettes/day | 513 | 5.7 | 1.34 (0.88 to 2.04) | 1.50 (0.97 to 2.29) | ||
| 15–50 cigarettes/day | 182 | 8.2 | 2.00 (1.14 to 3.51) | 2.21 (1.24 to 3.92) | ||
| Type of feeding | 0.212 | 0.053 | ||||
| Only formula | 2080 | 4.6 | 1.00 | 1.00 | ||
| Mixed breast and formula | 365 | 3.3 | 0.71 (0.39 to 1.31) | 0.57 (0.31 to 1.06) | ||
| Only breast | 871 | 5.5 | 1.22 (0.85 to 1.74) | 0.69 (0.48 to 1.01) | ||
| Type of feeding by maternal smoking | 0.146 | 0.023 | ||||
| Never smokes | 2588 | 4.3 | 1.00 | 1.00 | ||
| Smokes, only formula fed | 559 | 6.1 | 1.45 (0.97 to 2.15) | 1.81 (1.21 to 2.72) | ||
| Smokes, (partially) breastfed | 164 | 6.1 | 1.45 (0.74 to 2.82) | 1.18 (0.60 to 2.32) |
↵1-150 Numbers do not always add up to 3345 due to missing values.
↵1-151 Odds ratio adjusted for age of the infant.
↵1-152 p value for inclusion of the characteristic in the logistic model, after adjustment for age of the infant.
↵1-153 Age categories concerned the following intervals: 1 month = 3–5 weeks; 3 months = 11–15 weeks; 6 months = 22–30 weeks.