Table 2 Cross-comparison of indices of exposure among the study population: self-reported traffic, distance from high traffic roads (HTRs), metres of HTR 5 within 200 m from home, particulate matter (PM) emissions, estimated nitrogen dioxide (NO2)
n%Self-reported intense traffic (%)Distance from HTR, mean (SD)Metres of HTR within 200 m from home, mean (SD)PM emissions (kg/m2), mean (SD)Estimated NO2 (μg/m3), mean (SD)
Self-reported traffic
    Absent184619.5–756 (689)602 (408)0.067 (0.062)39.2 (8)
    Low309432.6–521 (491)575 (401)0.101 (0.073)43.9 (7)
    Intermediate306332.3–349 (388)659 (444)0.140 (0.075)47.8 (7)
    High141514.9–188 (387)854 (533)0.186 (0.074)51.5 (6)
    p Value<0.001<0.001<0.001<0.001
Distance from HTRs
    >200 m589862.27.4684 (566)–0.099 (0.074)43.4 (8)
    100–200 m168417.718.5149 (29)431 (329)0.149 (0.080)48.2 (7)
    50–100 m8138.625.176 (15)829 (404)0.154 (0.080)49.3 (7)
    <50 m101410.744.411 (17)988 (486)0.167 (0.080)49.5 (6)
    p Value<0.001––<0.001<0.001
Metres of HTR within 200 m from home
    None589862.27.4684 (566)–0.099 (0.074)43.4 (8)
    Low (<416 m)116912.318.1140 (54)232 (127)0.142 (0.077)48.2 (7)
    Medium (416–798 m)117712.425.689 (52)613 (111)0.148 (0.082)49.3 (7)
    High (>798 m)116512.338.947 (46)1209 (386)0.176 (0.077)49.5 (6)
    p Value<0.001––<0.001<0.001
PM emissions (quartiles)
    1st240625.42.7825 (746)595 (309)0.023 (0.014)34.6 (4)
    2nd235724.88.6457 (456)543 (377)0.087 (0.018)45.4 (4)
    3rd231224.416.0328 (302)638 (495)0.143 (0.022)47.9 (3)
    4th231124.433.2225 (230)829 (495)0.232 (0.043)54.1 (4)
    p Value<0.001<0.001<0.001–<0.001
Estimated NO2 (quartiles, μg/m3)
    1st (21.0–37.3)234624.72.7840 (770)595 (308)0.028 (0.028)33.7 (3)
    2nd (37.3–47.3)229124.16.2552 (444)574 (405)0.098 (0.042)44.6 (3)
    3rd (47.3–50.3)235424.816.2261 (211)594 (435)0.127 (0.032)48.6 (1)
    4th (50.3–62.6)236624.935.0194 (157)825 (517)0.227 (0.047)54.6 (4)
    p Value<0.001<0.001<0.001<0.001–

  • Totals may vary because of missing information.