Table 1 Summary statistics of daily hospital outpatient visits, weather conditions, and air pollutants in Dongguan (2013–2017)
Variable | Mean ± SD | Percentile | ||||
|---|---|---|---|---|---|---|
Min | P25 | P50 | P75 | Max | ||
Daily outpatients | ||||||
 Respiratory | 44 ± 11 | 3 | 38 | 44 | 52 | 89 |
 asthma | 17 ± 6 | 0 | 12 | 16 | 21 | 44 |
 COPD | 7 ± 3 | 0 | 4 | 6 | 8 | 21 |
 Bronchiectasis | 5 ± 3 | 0 | 3 | 5 | 6 | 15 |
Meteorological factors | ||||||
 Temperature (°C) | 23.2 ± 5.8 | 3.8 | 19.0 | 24.8 | 28.0 | 33.2 |
 Relative humidity (%) | 77.5 ± 13.4 | 22.0 | 70.0 | 79.0 | 87.0 | 100.0 |
Air pollution (μg/m3) | ||||||
 PM10 | 56.6 ± 28.3 | 7.7 | 35.5 | 49.4 | 71.0 | 217.9 |
 SO2 | 15.9 ± 8.4 | 3.1 | 10.0 | 13.8 | 19.3 | 60.3 |
 NO2 | 38.8 ± 16.3 | 9.0 | 27.4 | 36.0 | 47.0 | 137.3 |
 O3 | 62.0 ± 34.7 | 5.2 | 37.9 | 55.5 | 79.8 | 304.9 |