Table 1.
Summary statistics of TRAP exposures for each allergic disease and prevalence of three allergic diseases for each individual characteristic in 14,765 children from the Seoul Atopy Friendly School Project survey in 2010 in Seoul, Korea.
| Total | Prevalent cases (prevalence rate, %) | |||||||
|---|---|---|---|---|---|---|---|---|
| N (%) | Atopic eczema | Asthma | Allergic rhinitis | |||||
| 14,765 | (100) | 2,351 | (15.9) | 1,187 | (8.0) | 5,338 | (36.2) | |
| TRAP exposurea | ||||||||
| Proximityb | ||||||||
| 0–150 m | 4,494 | (30.4) | 724 | (30.8) | 314 | (26.5) | 1,601 | (30.0) |
| 150–300 m | 3,873 | (26.2) | 629 | (26.8) | 332 | (28.0) | 1,432 | (26.8) |
| 300–500 m | 3,284 | (22.2) | 536 | (22.8) | 261 | (22.0) | 1,193 | (22.3) |
| >500 m | 3,114 | (21.1) | 462 | (19.7) | 280 | (23.6) | 1,112 | (20.8) |
| Densityc (1,000 m2) | 7.2 | (8.6) | 7.5 | (8.8) | 6.7 | (8.2) | 7.1 | (8.6) |
|
| ||||||||
| Sex | ||||||||
| Girls | 7,356 | (49.8) | 1,198 | (16.3) | 468 | (6.4) | 2,341 | (31.8) |
| Boys | 7,409 | (50.2) | 1,153 | (15.6) | 719 | (9.7) | 2,997 | (40.5) |
| Age | ||||||||
| 1–3 | 1,322 | (9.0) | 223 | (16.9) | 235 | (17.8) | 369 | (27.9) |
| 4–6 | 2,447 | (16.6) | 450 | (18.4) | 271 | (11.1) | 890 | (36.4) |
| 7–9 | 5,453 | (36.9) | 898 | (16.5) | 386 | (7.1) | 2,089 | (38.3) |
| 10–12 | 5,543 | (37.5) | 780 | (14.1) | 295 | (5.3) | 1,990 | (35.9) |
| Body fatness | ||||||||
| Normal | 11,948 | (80.9) | 1,944 | (16.3) | 930 | (7.8) | 4,214 | (35.3) |
| Overweight or obese | 769 | (5.2) | 122 | (15.9) | 89 | (11.6) | 283 | (36.8) |
| Underweight | 2,048 | (13.9) | 285 | (13.9) | 168 | (8.2) | 841 | (41.1) |
| Breastfeeding duration | ||||||||
| <4 months | 8,042 | (54.5) | 1,124 | (14.0) | 597 | (7.4) | 2,977 | (37.0) |
| 4–11 | 3,876 | (26.3) | 637 | (16.4) | 318 | (8.2) | 1,342 | (34.6) |
| ≥12 | 2,847 | (19.3) | 590 | (20.7) | 272 | (9.6) | 1,019 | (35.8) |
| Residential area | ||||||||
| Downtown | 1,729 | (11.7) | 315 | (18.2) | 191 | (11.0) | 543 | (31.4) |
| Area 1 | 1,803 | (12.2) | 270 | (15.0) | 106 | (5.9) | 665 | (36.9) |
| Area 2 | 3,010 | (20.4) | 552 | (18.3) | 366 | (12.2) | 1,048 | (34.8) |
| Area 3 | 2,303 | (15.6) | 318 | (13.8) | 140 | (6.1) | 807 | (35.0) |
| Area 4 | 973 | (6.6) | 154 | (15.8) | 59 | (6.1) | 359 | (36.9) |
| Area 5 | 1,282 | (8.7) | 196 | (15.3) | 73 | (5.7) | 492 | (38.4) |
| Area 6 | 1,678 | (11.4) | 246 | (14.7) | 122 | (7.3) | 639 | (38.1) |
| Area 7 | 1,987 | (13.5) | 300 | (15.1) | 130 | (6.5) | 785 | (39.5) |
| Household SES | ||||||||
| High | 5,545 | (37.6) | 770 | (13.9) | 423 | (7.6) | 2,120 | (38.2) |
| Middle | 6,539 | (44.3) | 1,097 | (16.8) | 532 | (8.1) | 2,367 | (36.2) |
| Low | 2,681 | (18.2) | 484 | (18.1) | 232 | (8.7) | 851 | (31.7) |
| Regional SESd | ||||||||
| High | 2,702 | (18.3) | 469 | (17.4) | 250 | (9.3) | 902 | (33.4) |
| Middle | 6,991 | (47.3) | 1,116 | (16.0) | 628 | (9.0) | 2,494 | (35.7) |
| Low | 5,072 | (34.4) | 766 | (15.1) | 309 | (6.1) | 1,942 | (38.3) |
aNumber of children (percent) for each allergic disease is displayed for proximity, whereas mean (standard deviation) is presented for summarizing road density. bProximity is a categorical variable indicating children live within a specific distance from the closest major roads. cDensity is a continuous variable defined as the sum of road lengths multiplied by numbers of lanes and road widths of major roads within a 300 m radius buffer from a child's home. dRegional socioeconomic status (SES) was categorized based on fiscal self-sufficiency of residential areas (see Figure 2).