Time trends in known environmental trigger factors through the International Study of Asthma and Allergies in Childhood (ISAAC) Phase III and Global Asthma Network (GAN) in the two age groups of children
| 6–7-year age group | 13–14-year age group | |||||
| GAN (n=20 084) | ISAAC Phase III (n=47 166) | p-value# | GAN (n=25 887) | ISAAC Phase III (n=52 289) | p-value# | |
| Paracetamol use in last 12 months | ||||||
| Never | 6639 (33.1) | 8945 (19.0) | 0.000 | 9838 (38.0) | 14 689 (28.1) | 0.000 |
| At least once a year | 9496 (47.3) | 21 499 (45.6) | 10 283 (39.7) | 18 749 (35.9) | ||
| At least once per month | 2104 (10.5) | 5940 (12.6) | 4441 (17.2) | 9530 (18.2) | ||
| No response | 1845 (9.2) | 10 782 (22.8) | 1325 (5.1) | 9321 (17.8) | ||
| Farm animals during pregnancy¶ | ||||||
| Yes | 1307 (6.5) | 3357 (7.1) | 0.000 | |||
| No | 18 051 (89.9) | 34 474 (73.1) | ||||
| No response | 726 (3.6) | 9335 (19.8) | ||||
| Farm animals during first year of life¶ | ||||||
| Yes | 1059 (5.3) | 4267 (9.0) | 0.000 | |||
| No | 18 297 (91.1) | 33 585 (71.2) | ||||
| No response | 728 (3.6) | 9314 (19.8) | ||||
| Trucks pass through the street | ||||||
| Never | 9999 (49.8) | 9451 (20.0) | 0.374 | 11 063 (42.7) | 10 978 (21.0) | 0.000 |
| Seldom (not often) | 8631 (43.0) | 13 793 (29.2) | 9573 (37.0) | 15 354 (29.4) | ||
| Frequently through the day | 1028 (5.1) | 8276 (17.6) | 2902 (11.2) | 9550 (18.3) | ||
| Almost the whole day | 426 (2.1) | 5808 (12.3) | 1268 (4.9) | 2718 (5.2) | ||
| No response | 0 | 9838 (20.9) | 1081 (4.2) | 13 689 (26.2) | ||
| Child ever breastfed¶ | ||||||
| Yes | 16 569 (82.5) | 35 215 (74.7) | 0.000 | |||
| No | 2728 (13.6) | 2549 (5.4) | ||||
| No response | 787 (3.9) | 9402 (19.9) | ||||
| Cat in the home during first year of life¶ | ||||||
| Yes | 991 (4.9) | 3756 (8.0) | 0.000 | |||
| No | 18 360 (91.4) | 34 107 (72.3) | ||||
| No response | 733 (3.7) | 9303 (19.7) | ||||
| Cat in the home in last 12 months | ||||||
| Yes | 985 (4.9) | 3632 (7.7) | 0.000 | 3221 (12.4) | 8491 (16.2) | 0.000 |
| No | 17 875 (89.0) | 34 277 (72.7) | 22 041 (85.1) | 35 480 (67.9) | ||
| No response | 1224 (6.09) | 9257 (19.63) | 625 (2.5) | 8318 (15.9) | ||
| Dog in the home during first year of life¶ | ||||||
| Yes | 1102 (5.5) | 4102 (8.7) | 0.000 | |||
| No | 18 280 (91.0) | 33 836 (71.7) | ||||
| No response | 702 (3.5) | 9228 (19.6) | ||||
| Dog in the home in last 12 months | ||||||
| Yes | 1200 (6.0) | 3779 (8.0) | 0.000 | 3930 (15.2) | 7934 (15.2) | 0.000 |
| No | 18 150 (90.4) | 34 183 (72.5) | 21 394 (82.6) | 36 000 (68.8) | ||
| No response | 734 (3.6) | 9204 (19.5) | 563 (2.2) | 8355 (16.0) | ||
| Fast food | ||||||
| Never or only occasionally | 13 286 (66.2) | 10 754 (22.8) | 0.000 | 16 535 (63.9) | 12 553 (24.0) | 0.000 |
| Once or twice per week | 3445 (17.2) | 7383 (15.7) | 5200 (20.1) | 12 018 (23.0) | ||
| Most or all days | 462 (2.3) | 9865 (20.9) | 1690 (6.5) | 10 236 (19.6) | ||
| No response | 2891 (13.3) | 19 164 (40.3) | 2462 (9.5) | 17 482 (33.4) | ||
| Antibiotic in first year of life¶ | ||||||
| Yes | 3350 (16.7) | 17 706 (37.5) | 0.373 | |||
| No | 16 734 (83.3) | 17 711 (37.6) | ||||
| No response | 0 | 11 749 (24.9) | ||||
| Fresh fruit | ||||||
| Never or only occasionally | 4590 (22.9) | 11 179 (23.7) | 0.000 | 7698 (29.7) | 12 031 (23.0) | 0.000 |
| Once or twice per week | 6841 (34.1) | 12 503 (26.5) | 6106 (23.6) | 14 409 (27.6) | ||
| Most or all days | 6341 (31.6) | 11 511 (24.4) | 9255 (35.8) | 15 061 (28.8) | ||
| No response | 2312 (11.4) | 11 973 (25.4) | 2828 (10.9) | 10 788 (20.6) | ||
| Vegetables | ||||||
| Never or only occasionally | 5565 (27.7) | 12 291 (26.1) | 0.000 | 13 150 (50.8) | 12 721 (24.3) | 0.000 |
| Once or twice per week | 5792 (28.8) | 9395 (19.9) | 4666 (18.0) | 11 230 (21.5) | ||
| Most or all days | 5842 (29.1) | 13 726 (29.1) | 5193 (20.1) | 17 681 (33.8) | ||
| No response | 2885 (14.4) | 11 754 (24.9) | 2878 (11.1) | 10 657 (20.4) | ||
| Mother smoking during first year of life | ||||||
| Yes | 209 (1.0) | 385 (0.8) | 0.000 | |||
| No | 19 194 (95.6) | 37 637 (79.8) | ||||
| No response | 681 (3.4) | 9144 (19.4) | ||||
Data are presented as n (%), unless otherwise stated. #: Chi-squared test. ¶: questions included in the 6–7-year age group questionnaire only.