1Department of Preventive Medicine, Yonsei University College of Medicine, Seoul, Korea
2Department of Occupational and Environmental Medicine, Gachon University Gil Hospital, Incheon, Korea
3Department of Medical Informatics and Biostatistics, Yonsei University College of Medicine, Seoul, Korea
4Health Insurance Review and Assessment Service, Seoul, Korea
5Institute for Environmental Research, Yonsei University College of Medicine, Seoul, Korea
Copyright © 2016 The Korean Society for Preventive Medicine
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Characteristics | Total visits n (%) | Daily visits |
||||
---|---|---|---|---|---|---|
Mean±SD | 5th | 50th | 95th | IQR | ||
Gender | ||||||
Men | 15 526 (46.0) | 10±5.3 | 4 | 9 | 20 | 6 |
Women | 18 225 (54.0) | 8.5±4.1 | 3 | 8 | 16 | 5 |
Age (y) | ||||||
< 2 | 4131 (12.2) | 2.3±2 | 0 | 2 | 6 | 2 |
2-5 | 6820 (20.2) | 3.7±2.9 | 0 | 3 | 10 | 3 |
6-14 | 4524 (13.4) | 2.5±2.7 | 0 | 2 | 8 | 2 |
15-39 | 5138 (15.2) | 2.8±2.1 | 0 | 2 | 7 | 3 |
40-64 | 6247 (18.5) | 3.4±2 | 1 | 3 | 7 | 3 |
≥65 | 6891 (20.4) | 3.8±2.3 | 1 | 3 | 8 | 3 |
Prior allergic disease | ||||||
Without any history | 12 765 (37.8) | 7±4 | 2 | 6 | 14 | 5 |
AD or AR history | 4325 (12.8) | 2.4±1.9 | 0 | 2 | 6 | 2 |
Asthma history | 16 661 (49.4) | 9.1±4.5 | 3 | 9 | 17 | 5 |
Season | ||||||
Spring | 8712 (25.8) | 18.9±6.3 | 10 | 18 | 31 | 8 |
Summer | 6012 (17.8) | 13.1±4.9 | 6 | 13 | 22 | 7 |
Fall | 10 586 (31.4) | 23.3±10.1 | 11 | 21 | 42 | 12 |
Winter | 8441 (25.0) | 18.7±7.4 | 10 | 17 | 33 | 9 |
Total | 33 751 (100) | 18.5±8.5 | 8 | 17 | 34 | 9 |
Pollutant | Units | Daily variation |
Seasonal variation (Mean±SD) |
|||||||
---|---|---|---|---|---|---|---|---|---|---|
Mean±SD | 5th | 50th | 95th | IQR | Spring | Summer | Fall | Winter | ||
O3 (8-h maximum) | ppb | 31.7±17.0 | 8.1 | 28.9 | 63.0 | 22.6 | 72.3±60.6 | 46.7±26.0 | 48.6±28.5 | 62.5±32.2 |
CO (daily mean) | ppm | 0.6±0.3 | 0.3 | 0.5 | 1.1 | 0.3 | 41.1±13.2 | 42.7±18.6 | 27.3±12.3 | 17.1±7.7 |
NO2 (daily mean) | ppb | 36.3±12.7 | 18.6 | 34.9 | 59.2 | 18.3 | 0.6±0.2 | 0.4±0.1 | 0.6±0.2 | 0.8±0.3 |
SO2 (daily mean) | ppb | 5.7±2.5 | 3.1 | 5.0 | 10.7 | 2.8 | 5.7±2.3 | 4.2±1.0 | 4.9±1.9 | 7.8±2.7 |
PM10 (daily mean) | pg/m3 | 57.6±38.9 | 18.1 | 50.2 | 119.6 | 35.5 | 38.7±12.2 | 28.7±8.7 | 35.2±11.9 | 40.7±13.4 |
Temperature (daily mean) | °C | 12.9±10.2 | -4.3 | 14.6 | 26.6 | 17.7 | 12.4±5.9 | 24±2.8 | 15.2±6.5 | -0.3±4.3 |
Relative humidity | % | 60.8±14.8 | 36.4 | 61.4 | 85.0 | 21.9 | 54.8±15.2 | 71.1±12.1 | 62.5±12.0 | 54.1±12.9 |
Vapor pressure | hPa | 11.3±7.9 | 1.9 | 9.0 | 26.1 | 12.6 | 8.2±3.7 | 21.3±4.7 | 11.8±5.3 | 3.5±1.7 |
SD, standard deviation; IQR, interquartile range; AD, atopic dermatitis; AR, allergic rhiniti; Spring, March to May; Summer, June to August; Fall, September to November; Winter, December to February.
SD, standard deviation; IQR, interquartile range; Spring, March to May; Summer, June to August; Fall, September to November; Winter, December to February; O3, ozone; CO, carbon monoxide; NO2, nitrogen dioxide; SO2, sulfur dioxide; PM10, particulate matter with an aerodynamic diameter <10 μm.