Table 2.
Categorical variables and ORs
| Questiona/variable | Cases
|
Controls
|
OR | 95% CI | p-value |
|---|---|---|---|---|---|
| n (%) | n (%) | ||||
| Duration of breastfeeding? | |||||
| Never breastfed | 234 (23.4) | 70 (13.6) | 1.935 | 1.446–2.590 | <0.0001* |
| 3 months or less | 277 (27.7) | 80 (15.6) | 2.076 | 1.575–2.735 | <0.0001* |
| >3 months and up to 6 months | 118 (11.8) | 66 (12.8) | 0.907 | 0.657–1.252 | 0.5527 |
| >6 months and up to 12 months | 155 (15.5) | 90 (17.5) | 0.863 | 0.649–1.147 | 0.3107 |
| >12 months | 217 (21.7) | 208 (40.5) | 0.407 | 0.323–0.513 | <0.0001* |
| Courses of antibiotics up to second birthday? | |||||
| None | 194 (19.4) | 141 (27.4) | 0.667 | 0.519–0.858 | 0.0015* |
| 1 | 174 (17.4) | 132 (25.7) | 0.638 | 0.492–0.826 | 0.0006* |
| 2–3 | 282 (28.2) | 133 (25.9) | 1.196 | 0.938–1.526 | 0.1483 |
| 4–7 | 181 (18.1) | 64 (12.5) | 1.642 | 1.206–2.236 | 0.0015* |
| 8–15 | 71 (7.1) | 19 (3.7) | 2.086 | 1.242–3.504 | 0.0046* |
| 16+ | 18 (1.8) | 4 (0.8) | 2.440 | 0.821–7.249 | 0.0975 |
| I’m not sure | 81 (8.1) | 21 (4.1) | – | – | – |
| Ear infections up to second birthday? | |||||
| None | 341 (34.1) | 230 (44.7) | 0.644 | 0.517–0.802 | 0.0001* |
| 1 | 179 (17.9) | 115 (22.4) | 0.764 | 0.587–0.994 | 0.0446* |
| 2–3 | 208 (20.8) | 76 (14.8) | 1.533 | 1.149–2.044 | 0.0035* |
| >3 or persistent | 246 (24.6) | 84 (16.3) | 1.694 | 1.286–2.230 | 0.0002* |
| I’m not sure | 27 (2.7) | 9 (1.8) | – | – | – |
| Doses of acetaminophen up to second birthday? | |||||
| None | 54 (5.4) | 45 (8.8) | 0.652 | 0.432–0.986 | 0.0414* |
| 1–3 | 174 (17.4) | 91 (17.7) | 1.096 | 0.825–1.456 | 0.5266 |
| 4–15 | 378 (37.8) | 216 (42.0) | 0.971 | 0.773–1.220 | 0.8029 |
| 16–63 | 191 (19.1) | 107 (20.8) | 1.006 | 0.768–1.317 | 0.9682 |
| 64+ | 26 (2.6) | 4 (0.8) | 3.743 | 1.298–10.793 | 0.0089* |
| I’m not sure | 178 (17.8) | 51 (9.9) | – | – | – |
| Doses of ibuprofen up to second birthday? | |||||
| None | 185 (18.5) | 115 (22.4) | 0.898 | 0.687–1.172 | 0.4279 |
| 1–3 | 167 (16.7) | 91 (17.7) | 1.064 | 0.800–1.415 | 0.6716 |
| 4–15 | 304 (30.4) | 180 (35.0) | 0.947 | 0.749–1.197 | 0.6495 |
| 16–63 | 141 (14.1) | 74 (14.4) | 1.110 | 0.816–1.510 | 0.5067 |
| 64+ | 17 (1.7) | 6 (1.2) | 1.635 | 0.640–4.177 | 0.2993 |
| I’m not sure | 187 (18.7) | 48 (9.3) | – | – | – |
| Duration of vitamin D drops as a baby? | |||||
| No vitamin D drops | 642 (64.1) | 307 (59.7) | 1.475 | 1.165–1.866 | 0.0012* |
| 3 months or less | 108 (10.8) | 85 (16.5) | 0.646 | 0.474–0.879 | 0.0053* |
| >3 months and up to 6 months | 62 (6.2) | 44 (8.6) | 0.746 | 0.498–1.117 | 0.1534 |
| >6 months and up to 12 months | 50 (5.0) | 30 (5.8) | 0.898 | 0.563–1.432 | 0.6499 |
| >12 months | 31 (3.1) | 18 (3.5) | 0.931 | 0.515–1.682 | 0.8128 |
| I’m not sure | 108 (10.8) | 30 (5.8) | – | – | – |
| Dosage of vitamin D drops as a baby? | |||||
| No vitamin D drops | 641 (64.0) | 308 (59.9) | 1.489 | 1.173–1.891 | 0.0010* |
| Less than the standard dose | 12 (1.2) | 17 (3.3) | 0.376 | 0.178–0.793 | 0.0077* |
| About the standard dose | 220 (22.0) | 149 (29.0) | 0.738 | 0.577–0.945 | 0.0156* |
| More than the standard dose | 7 (0.7) | 5 (1.0) | 0.760 | 0.240–2.408 | 0.6401 |
| I’m not sure | 121 (12.1) | 35 (6.8) | – | – | – |
| Prenatal folate supplementation? | |||||
| Yes, for the entire or nearly entire pregnancy | 788 (78.7) | 421 (81.9) | 0.849 | 0.634–1.137 | 0.2718 |
| Yes, during the first trimester | 55 (5.5) | 29 (5.6) | 0.985 | 0.620–1.566 | 0.9489 |
| Yes, after the first trimester | 45 (4.5) | 15 (2.9) | 1.587 | 0.876–2.876 | 0.1249 |
| No | 72 (7.2) | 34 (6.6) | 1.109 | 0.726–1.693 | 0.6318 |
| I’m not sure | 41 (4.1) | 15 (2.9) | – | – | – |
Notes:
a
Questions in this table were edited for brevity.
*
p-values <0.05.
Abbreviation: OR, Wald Odds Ratio.