Table 1.
Frequency of reported truck traffic density percentages in the various regions of the world where 13- to 14-year-old children were studied as part of the ISAAC phase 3 study.
| No. |
Percenta |
||||||
|---|---|---|---|---|---|---|---|
| Country | Center | Total | High | Medium | Low | Never | |
| All centers | 46 | 110 | 315,572 | 15.9 | 23.7 | 42.8 | 17.6 |
| Africa | 5 | 7 | 16,914 | 31.6 | 20.5 | 28.7 | 19.2 |
| Asia-Pacific | 7 | 15 | 49,707 | 12.5 | 20.6 | 45.2 | 21.7 |
| Eastern Mediterranean | 4 | 7 | 22,745 | 16.2 | 24.9 | 49.4 | 9.5 |
| Indian subcontinent | 1 | 16 | 43,298 | 17.2 | 22.0 | 35.4 | 25.4 |
| Latin America | 10 | 27 | 76,375 | 20.7 | 23.5 | 38.5 | 17.3 |
| North America | 3 | 3 | 6,452 | 10.9 | 24.1 | 49.9 | 15.1 |
| Northern and Eastern Europe | 7 | 10 | 30,026 | 11.6 | 23.7 | 55.0 | 9.7 |
| Oceania | 3 | 7 | 19,002 | 17.8 | 27.1 | 39.5 | 15.6 |
| Western Europe | 6 | 18 | 51,053 | 7.9 | 27.7 | 47.9 | 16.5 |
a
High, almost the whole day; medium, frequently during the day; low, seldom.