Table 1 Characteristics of subjects participated and not participated in this study
| Â | Participants | Non-participants | P-value |
|---|---|---|---|
n = 543 | n = 953 | ||
Baseline characteristics | |||
 Age, mean ± SD, year | 69.5 ± 4.1 | 70.4 ± 4.28 | < 0.0001 |
 Male, n (%) | 216 (39.8) | 417 (43.8) | 0.134 |
 Height, mean ± SD, cm | 158.1 ± 7.9 | 157.8 ± 7.9 | 0.470 |
 Weight, mean ± SD, kg | 61.9 ± 10.0 | 61.4 ± 10.0 | 0.339 |
 Education < 13 year, n (%) | 262 (48.3) | 566 (59.4) | < 0.0001 |
Smoking status, n (%) | |||
 Never | 445 (82.0) | 783 (82.2) | 0.855 |
 Former | 72 (13.3) | 130 (13.64) | |
 Current | 26 (4.8) | 40 (4.2) | |
Pack-years*, mean ± SD | 18.5 (13.3) | 20.3 (15.7) | 0.325 |
Dusty job history, n (%) | 86 (15.8) | 190 (19.9) | 0.049 |
SHS exposure, min per month, mean ± SD | 160.6 ± 1154.4 | 245.6 ± 1780.2 | 0.318 |
Cooking (frying), min per month, mean ± SD | 666.5 ± 1175.2 | 721.8 ± 1389.0 | 0.435 |
Incense burning at home, n (%) | |||
 Never | 258 (47.5) | 433 (45.4) | 0.382 |
 < Once a week | 10 (1.8) | 29 (3.0) | |
 Once to trice a week | 60 (11.1) | 121 (12.7) | |
 > Trice a week | 215 (39.6) | 370 (38.8) | |
Using range hood when cooking (frying), n (%) | 482 (88.8) | 846 (88.8) | 0.997 |
Asthma, n (%) | 13 (2.4) | 20 (2.1) | 0.708 |
Regular treatment for asthma, n (%) | 6 (1.1) | 12 (1.3) | 0.795 |
Chronic airway diseases, n (%) | 14 (2.6) | 17 (1.8) | 0.300 |
Regular treatment for chronic airway diseases, n (%) | 7 (1.3) | 12 (1.3) | 0.960 |