Table 3.
Follow-up Air Quality Measurements by Group
| Measure | Control Group (n=42) |
Air Cleaner Group (n=35) |
Air Cleaner Plus Health Coach Group (n=38) |
P Value | |
|---|---|---|---|---|---|
| PM2.5 level, μg/m3 | |||||
| Mean(SD) (n = 96) | 38.9 (25.0) | 17.9 (15.2) | 32.2 (30.1) |  |
.003 |
| Differencea (n = 86) | 3.5 (20.0) | −19.9 (28.2) | −16.1 (38.2) | ||
| PM2.5–10 level, μg/m3 | |||||
| Mean(SD) (n = 92) | 18.0 (15.8) | 11.0 (7.4) | 13.5 (10.1) |  |
.02 |
| Differencea (n = 78) | 2.4 (20.8) | −8.7 (17.4) | −10.6 (14.7) | ||
| Air nicotine concentration, μg/m3 | |||||
| Mean(SD) (n = 103) | 1.4 (2.04) | 0.9 (1.7) | 0.9 (1.1) |  |
.94 |
| Differencea (n = 93) | −0.4 (2.31) | −0.3 (1.9) | −0.6 (1.8) | ||
| Urine cotinine concentration, ng/mL | |||||
| Mean(SD)(n = 115) | 24.3 (27.4) | 18.8 (24.1) | 22.0 (28.9) |  |
.85 |
| Differencea (n = 110) | −2.0 (26.6) | −2.4 (35.4) | −1.4 (25.6) |
Abbreviations: PM2.5, particulate matter with an aerodynamic diameter of less than 2.5 μm; PM2.5–10, particulate matter with a difference between particles with an aerodynamic diameter of 10 and 2.5 μm.
a
Indicates mean 6-month concentration minus the baseline concentration. Kruskal-Wallis tests were used to compare differences among the 3 groups.