Cotinine (ng/ml) | Baseline | 3 month | 6 month | 12-month | p Value* | Trend† |
---|---|---|---|---|---|---|
*p Values from baseline to 12 month follow up Wilcoxon sign rank test. | ||||||
†p Values from Cuzick non-parametric trend test across all waves. | ||||||
Mean cotinine | 3.6 (2.56 to 4.67) 24 | 1.7 (1.44 to 2.0) 24 | 1.9 (1.42 to 2.3) 24 | 0.78 (0.37 to 1.19) 24 | <0.001 | <0.001 |
Mean cotinine (excludes respondents with undetectable cotinine at baseline) | 4.7 (3.36 to 5.98) 16 | 1.8 (1.41 to 2.25) 16 | 2.02 (1.35 to 2.69) 16 | 0.83 (0.27 to 1.4) 16 | <0.001 | <0.001 |