Table 2

Lag-specific associations of PM2.5, NO2 and O3 levels with hospital admissions for autism spectrum disorder†

PM2.5NO2O3
RR (95% CI)RR (95% CI)RR (95% CI)
Lag day 00.87 (0.81 to 0.92)*0.84 (0.77 to 0.97)*0.99 (0.94 to 1.04)
Lag day 11.17 (1.10 to 1.25)*1.03 (0.91 to 1.18)1.02 (0.97 to 1.07)
Lag day 21.04 (1.00 to 1.08)0.95 (0.90 to 1.03)0.99 (0.95 to 1.02)
Lag day 30.97 (0.93 to 1.02)0.97 (0.91 to 1.06)1.00 (0.96 to 1.03)
Lag day 40.99 (0.96 to 1.02)1.06 (1.00 to 1.14)1.03 (1.00 to 1.06)*
Lag day 51.00 (0.96 to 1.04)1.09 (1.01 to 1.18)*1.03 (1.00 to 1.07)
Lag day 60.97 (0.94 to 1.00)1.01 (0.96 to 1.07)0.99 (0.96 to 1.01)
  • *P<0.05.

  • †The results are presented for a 10.0 µg/m3 increase for PM2.5 and 10.0 ppb for NO2 and O3 from models adjusted for region, day, temperature, relative humidity and population.

  • NO2, nitrogen dioxide; O3, ozone; PM2.5, particulate matter; RR, relative risk.