TABLE 2.
Background Characteristics of Age at Introduction to Gluten and Breastfeeding Duration, by Country
| Variable | United States (n = 2542) | Finland (n = 1472) | Germany (n = 380) | Sweden (n = 2042) | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| n (%) | Mean ± SD | Median (Q1, Q3) | n (%) | Mean ± SD | Median (Q1, Q3) | n (%) | Mean ± SD | Median (Q1, Q3) | n (%) | Mean ± SD | Median (Q1, Q3) | |
| Time to gluten introduction, wk | 2542 | 30.1 ± 8.4 | 30.4 (26.1, 34.9) | 1472 | 27.8 ± 8.1 | 26.1 (23.9, 30.4) | 380 | 32.8 ± 10.4 | 30.4 (26.1, 37.0) | 2042 | 21.6 ± 4.5 | 21.7 (17.4, 23.9) |
| Category of age at gluten introduction | ||||||||||||
| Early (<17 wk)a | 98 (4) | 11.6 ± 3.9 | 13.0 (11.0, 14.0) | 47 (3) | 7.8 ± 4.1 | 7.0 (4.3, 10.0) | 18 (5) | 14.5 ± 1.9 | 14.0 (14.0, 16.0) | 233 (11) | 15.0 ± 1.6 | 15.3 (14.0, 16.0) |
| Reference (17–26 wk)a | 447 (18) | 21.0 ± 2.2 | 21.7 (19.6, 21.7) | 463 (32) | 22.1 ± 1.8 | 21.7 (21.7, 23.9) | 53 (14) | 22.0 ± 1.9 | 21.7 (19.6, 23.9) | 1330 (65) | 20.6 ± 2.3 | 21.7 (18.0, 21.7) |
| Late (>26 wk)a | 1997 (78) | 33.0 ± 6.6 | 30.4 (26.1, 34.9) | 962 (65) | 31.5 ± 6.7 | 30.4 (26.1, 34.9) | 309 (81) | 35.7 ± 9.2 | 32.6 (29.3, 39.1) | 479 (24) | 27.7 ± 2.9 | 26.1 (26.1, 28.3) |
| Duration of exclusive breastfeeding, wkb | 2542 | 5.4 ± 8.3 | 1.0 (0.07, 8.0) | 1472 | 7.2 ± 8.6 | 3.0 (0.07, 13.0) | 380 | 10.1 ± 11.1 | 4.0 (0.07, 21.7) | 2042 | 7.5 ± 7.8 | 4.0 (0.07, 16.0) |
| Duration of any breastfeeding, wkb | 2542 | 38.4 ± 34.0 | 34.6 (10.0, 56.6) | 1472 | 39.4 ± 24.7 | 39.1 (21.7, 54.6) | 380 | 36.5 ± 27.2 | 34.7 (14.1, 49.3) | 2042 | 32.7 ± 22.7 | 31.9 (17.4, 43.4) |
a
Mean ± SD and median (Q1,Q3) are presented for each category of age at gluten introduction
b
Children who were not breastfed were assigned a duration of 0. A total of 124 children in the United States, 0 children in Finland, 7 children in Germany, and 9 children in Sweden were not breastfed