. 2006 Feb 7;61(4):290–295. doi: 10.1136/thx.2005.051524

Table 2 Adjusted mean (95% CI) of lung function indices in control group and exposure groups.

	Control group (n = 211)	Low exposure (n = 238)	Moderate exposure (n = 237)	High exposure (n = 237)
FVC (l)†‡	5.06 (4.93 to 5.19)	4.84 (4.72 to 4.96)*	4.73 (4.60 to 4.84)**	4.74 (4.62 to 4.86)**
FEV₁ (l)†‡	4.27 (4.15 to 4.40)	4.04 (3.92 to 4.16)**	3.89 (3.76 to 4.00)**	3.85 (3.73 to 3.97)**
FEV₁/FVC (%)†‡	84.39 (83.00 to 85.77)	83.23 (81.93 to 84.53)	82.02 (80.70 to 83.35)*	80.12 (78.79 to 81.44)**
FEV₁ (% pred)†‡	101.60 (98.60 to 104.60)	95.50 (92.68 to 98.32)**	92.22 (89.34 to 95.10)**	92.22 (89.44 to 95.09)**

*p<0.05, **p<0.01 v control group.

†Mean (95% CI) adjusted for sex, age (<30, 30–34, 35–39, and ⩾40 years), height (<164, 164–167, 168–171, and ⩾172 cm) and cigarette‐years of smoking (0, 1–99, 100–199, 200–299 and ⩾300).

‡p<0.01, linear trend test across control group to high exposure group.