Cowie CT, Ezz W, Xuan W, et al. A randomised cross-over cohort study of exposure to emissions from a road tunnel ventilation stack. BMJ Open 2012;2:e001201. Spacing in table 3 was inaccurate and missed some header rows. The corrected table is below. Also, in the third paragraph of the section entitled “Health outcomes” the sentence “... higher scores for EYE, CHEST and THROAT symptoms (last row, table 3)” should actually be “higher scores for EYE and CHEST symptoms (table 3).” In addition, the volume number should be listed as “2” in this article. We apologise for these errors.
Table 3.
Contrasts* in lung function, eNO and symptom scores between the downwind site and the other two sites (upwind and heavily trafficked) adjusted for change from baseline (2006) to subsequent years
| Contrast* |
FEV1 (diff in litres) (95% CI) | FVC (diff in litres) (95% CI) | eNO Ratio (95% CI) | EYE symptoms (diff in score) (95% CI) | THROAT symptoms (diff in score) (95% CI) | |
|---|---|---|---|---|---|---|
| Location | Year | |||||
| Downwind vs (Heavily trafficked and Upwind)† | 2007/08 vs 2006‡ | 0.01 (−0.04–0.06) | 0.03 (−0.03–0.09) | 1.03 (0.94–1.12) | −0.006 (−0.097–0.086) | 0.130 (−0.084–0.344) |
| 2007 vs 2006 | 0.03 (−0.03–0.09) | 0.05 (−0.03–0.13) | 1.01 (0.91–1.11) | −0.055 (−0.159–0.049) | 0.041 (−0.220–0.301) | |
| 2008 vs 2006 | −0.004 (−0.07–0.06) | 0.02 (−0.07–0.10) | 1.05 (0.94–1.17) | 0.043 (−0.074–0.159) | 0.207 (−0.027–0.441) | |
| Downwind vs Upwind | 2007/08 vs 2006‡ | 0.02 (−0.04–0.08) | 0.06 (−0.02–0.13) | 1.03 (0.93–1.14) | −0.044 (−0.151–0.063) | 0.080 (−0.169–0.329) |
| 2007 vs 2006 | 0.04 (−0.03–0.11) | 0.06 (−0.03–0.15) | 1.05 (0.94–1.17) | −0.108 (−0.229–0.012) | −0.006 (−0.308–0.297) | |
| 2008 vs 2006 | 0.004 (−0.07–0.08) | 0.06 (−0.04–0.15) | 1.01 (0.89–1.15) | 0.015 (−0.120–0.149) | 0.179 (−0.092–0.449) | |
| Downwind vs Heavily trafficked | 2007/08 vs 2006‡ | −0.00 (−0.06–0.06) | 0.004 (−0.07–0.08) | 1.03 (0.93–1.14) | 0.033 (−0.073–0.140) | 0.180 (−0.068–0.428) |
| 2007 vs 2006 | 0.02 (−0.05–0.09) | 0.04 (−0.05–0.12) | 0.97 (0.87–1.08) | −0.002 (−0.121–0.117) | 0.087 (−0.212–0.385) | |
| 2008 vs 2006 | −0.01 (−0.09–0.06) | −0.03 (−0.12–0.07) | 1.09 (0.96–1.23) | 0.071 (−0.065–0.206) | 0.236 (−0.038–0.509) | |
| Heavily trafficked vs (Upwind and Downwind)§ | Overall | −0.01 (−0.04–0.01) | −0.03 (−0.06–0.002) | 1.09 (1.04–1.14) | 0.054 (0.006–0.102) | 0.107 (−0.005–0.218) |
| Contrast* |
CHEST symptoms (diff in score) (95% CI) | SNEEZE symptoms (diff in score) (95% CI) | DRY NOSE symptoms (diff in score) (95% CI) | SMELL-STRONG Odds ratio (95% CI) | SMELL-ANNOYING Odds ratio (95% CI) | |
| Location | Year | |||||
| Downwind vs (Heavily trafficked and Upwind)† | 2007/08 vs 2006‡ | −0.080 (−0.302–0.142) | 0.288 (−0.139–0.716) | 0.276 (0.040–0.511) | 3.45 (1.57–7.60) | 1.69 (0.72–3.96) |
| 2007 vs 2006 | −0.031 (−0.277–0.214) | 0.375 (−0.093–0.844) | 0.320 (0.053–0.587) | 5.72 (2.35–13.91) | 1.95 (0.77–4.94) | |
| 2008 vs 2006 | −0.133 (−0.409–0.143) | 0.182 (−0.254–0.618) | 0.229 (−0.057–0.516) | 2.14 (0.77–5.97) | 1.33 (0.44–4.00) | |
| Downwind vs Upwind | 2007/08 vs 2006‡ | −0.017 (−0.275–0.242) | 0.430 (−0.067–0.927) | 0.193 (−0.081–0.466) | 3.51 (1.40–8.80) | 1.23 (0.45–3.40) |
| 2007 vs 2006 | 0.033 (−0.252–0.318) | 0.422 (−0.123–0.966) | 0.187 (−0.124–0.498) | 4.11 (1.48–11.43) | 1.12 (0.38–3.37) | |
| 2008 vs 2006 | −0.042 (−0.362–0.277) | 0.424 (−0.080–0.929) | 0.178 (−0.154–0.510) | 3.31 (0.98–11.18) | 1.26 (0.34–4.71) | |
| Downwind vs Heavily trafficked | 2007/08 vs 2006‡ | −0.143 (−0.400–0.114) | 0.147 (−0.349–0.642) | 0.358 (0.086–0.631) | 3.39 (1.39–8.29) | 2.31 (0.90–5.94) |
| 2007 vs 2006 | −0.096 (−0.377–0.185) | 0.329 (−0.208–0.866) | 0.453 (0.146–0.759) | 7.96 (2.89–21.93) | 3.38 (1.20–9.54) | |
| 2008 vs 2006 | −0.224 (−0.547–0.099) | −0.060 (−0.570–0.450) | 0.281 (−0.054–0.617) | 1.38 (0.44–4.40) | 1.40 (0.41–4.75) | |
| Heavily trafficked vs (Upwind and Downwind)§ | Overall | 0.209 (0.094–0.325) | 0.150 (−0.072–0.372) | 0.022 (−0.101–0.144) | 2.34 (1.58–3.49) | 4.08 (2.67–6.25) |
*Contrasts are derived from mixed effects regression model in which location and year, and the interaction between them are fixed effects, and individual subject intercepts are a random effect. Main contrasts of interest are those included in the table and consist of downwind versus other exposures, as the downwind exposure is the primary exposure of interest in this study.
†Downwind vs (heavily trafficked and upwind) is the comparison of downwind versus heavily trafficked and upwind exposures combined.
‡2007/08 vs 2006 represents the comparison of both post-tunnel years combined (2007/08) versus the pre-tunnel year (2006).
§Represents the overall comparison of the heavily trafficked site compared to the upwind and downwind sites combined (data from all years included), as we anticipated the heavily trafficked site to have higher air pollution levels and that health effects would be more prominent.