Table 2.
Comparison between indoor (kitchen, sleeping area, ETS) risk exposures among respondents in winter and summer
| Variables | Winter | Summer | χ2a | p value |
|---|---|---|---|---|
| Number of respondents (percentage,%) (n = 1207) | Number of respondents (percentage,%) (n = 610) | |||
| Kitchen location | ||||
| Separated from other rooms | 1158 (95.9) | 587 (96.2) | 0.089 | 0.756 |
| Within living rooms or bedrooms | 49 (4.1) | 23 (3.8) | ||
| Kitchen size | ||||
| ≥ 4 m2 | 1042 (86.3) | 526 (86.2) | 0.003 | 0.095 |
| < 4 m2 | 165 (13.7) | 84 (13.8) | ||
| Frequency of opening kitchen windows | ||||
| Occasionally or never | 45 (3.7) | 0 (0) | 49.822 | < 0.001*** |
| Sometimes | 118 (9.8) | 20 (3.3) | ||
| Most of the time | 142 (11.8) | 78 (12.8) | ||
| Always | 902 (74.7) | 512 (83.9) | ||
| Stove used for cooking or warming | ||||
| Clean fuel stove | 476 (39.4) | 371 (60.8) | 188.560 | < 0.001*** |
| Fuel mix stove | 263 (21.8) | 190 (31.1) | ||
| Coal stove | 468 (38.8) | 49 (8.1) | ||
| Duration of cooking per day | ||||
| < 30 min | 581 (48.1) | 384 (63.0) | 90.253 | < 0.001*** |
| 30–60 min | 534 (44.2) | 136 (22.3) | ||
| > 60 min | 92 (7.6) | 90 (14.8) | ||
| Cooking oil fumes | ||||
| Never or seldom | 819 (67.9) | 427 (70.0) | 0.866 | 0.352 |
| Frequently or sometimes | 388 (32.1) | 183 (30.0) | ||
| Frequency of fan or range hood usage | ||||
| Never | 65 (5.4) | 22 (3.6) | 102.680 | < 0.001*** |
| Seldom | 46 (3.8) | 107 (17.5) | ||
| Sometimes | 183 (15.2) | 97 (15.9) | ||
| Always | 913 (75.6) | 384 (3.0) | ||
| Kitchen infested with pests | ||||
| Never | 1071 (88.7) | 553 (86.2) | 7.730 | 0.021* |
| Seldom | 122 (10.1) | 43 (8.4) | ||
| Sometimes | 14 (1.2) | 14 (5.4) | ||
| Person(s) sharing in one bedroom | ||||
| ≥ 3 persons | 222 (18.4) | 113 (18.5) | 0.005 | 0.945 |
| < 3 persons | 985 (81.6) | 497 (81.5) | ||
| Carpet | ||||
| No | 1134 (94.0) | 579 (94.9) | 0.701 | 0.402 |
| Yes | 73 (6.0) | 31 (5.1) | ||
| Carpet use history (years) | ||||
| ≤ 1 y | 1143 (94.7) | 584 (95.7) | 1.412 | 0.494 |
| 1–5 y | 49 (4.1) | 18 (3.0) | ||
| > 5 y | 15 (1.2) | 8 (1.3) | ||
| Mattress material | ||||
| Cloth or no mattress | 785 (65.0) | 503 (82.5) | 83.037 | <0.001*** |
| Foam or grass/grain husks | 251 (20.8) | 95 (15.6) | ||
| Feather or hairpiece | 171 (14.2) | 12 (2.0) | ||
| Mattress use history (years) | ||||
| ≤ 1 y | 509 (42.2) | 279 (45.7) | 2.156 | 0.340 |
| 1–5 y | 582 (48.2) | 274 (44.9) | ||
| > 5 y | 116 (9.6) | 57 (9.3) | ||
| Pillow material stuffed | ||||
| Cloth or no pillow | 954 (79.1) | 535 (87.7) | 45.642 | <0.001*** |
| Grass or foam | 127 (10.5) | 65 (10.7) | ||
| Feather | 126 (10.4) | 10 (1.6) | ||
| Keep pets | ||||
| No | 937 (68.9) | 487 (79.8) | 106.246 | <0.001*** |
| Yes | 270 (31.1) | 123 (20.2) | ||
| Pet allowed in bedroom | ||||
| No | 1135 (94.0) | 568 (93.1) | 0.583 | 0.445 |
| Yes | 72 (6.0) | 42 (6.9) | ||
| Water damage | ||||
| No | 1112 (92.1) | 575 (94.3) | 2.775 | 0.096 |
| Yes | 95 (7.9) | 35 (5.7) | ||
| Musty air in bedroom | ||||
| No | 1108 (91.8) | 586 (96.1) | 11.694 | 0.001** |
| Yes | 99 (8.2) | 24 (3.9) | ||
| Mold in bedroom | ||||
| No | 1122 (93.0) | 593 (97.2) | 13.848 | <0.001*** |
| Yes | 85 (7.0) | 17 (2.8) | ||
| New furniture | ||||
| No | 1119 (92.7) | 593 (97.2) | 15.097 | <0.001*** |
| Yes | 88 (7.3) | 17 (2.8) | ||
| Decoration and fitment | ||||
| No | 1147 (95.0) | 599 (98.2) | 10.829 | 0.001** |
| Yes | 60 (5.0) | 11 (1.8) | ||
| Smoking status | ||||
| Non-smokers | 688 (57.0) | 365 (59.8) | 1.803 | 0.406 |
| Ex-smokers | 167 (13.8) | 85 (13.9) | ||
| Current smokers | 352 (29.2) | 160 (26.2) | ||
| Exposure to second-hand smoke, ETS | ||||
| Yes | 222 (18.4) | 518 (84.4) | 742.80 | < 0.001*** |
| No | 985 (81.6) | 92 (15.6) | ||
Values are number (%). a Chi-squared test, α = 0.05, *significant at p < 0.05, **significant at p < 0.01, *** significant at p < 0.001