From: Directly measured secondhand smoke exposure and COPD health outcomes
Measure | N | Proportion with any self-reported exposure or detectable urine/badge level | SHS exposure among those with any exposure | ||
---|---|---|---|---|---|
 |  |  | 25th %tile | Median | 75th %tile |
Self-report, past 7 days (hrs) | 77 | 20 (26%) | 1 | 2 | 7 |
Urine cotinine (ng/ml) | 77 | 69 (90%) | 0.092 | 0.20 | 0.81 |
   First tertile* | 26 | 14 (54%) | 0 | 0.054 | 0.069 |
   Second tertile | 26 | 26 (100%) | 0.12 | 0.16 | 0.22 |
   Third tertile | 25 | 25 (100%) | 0.75 | 1.54 | 3.86 |
Personal nicotine badge (μg/m3) | 77 | 64 (83%) | 0.096 | 0.22 | 0.63 |
   First tertile* | 27 | 14 (52%) | 0 | 0.023 | 0.061 |
   Second tertile | 24 | 24 (100%) | 0.12 | 0.14 | 0.22 |
   Third tertile | 26 | 26 (100%) | 0.45 | 0.86 | 1.53 |