Table 2

Linear regression of exposure to environmental tobacco smoke and lung function in never smoking employees

Variable		Adjustment^2-150		FEV₁			FVC
Variable		Adjustment^2-150		β	p Value		β	p Value
Environmental tobacco smoke at work (score 1–4)^2-151
	1	−0.078	0.004		−0.096	0.006
	2	−0.085	0.003		−0.092	0.010
	3	−0.084	0.003		−0.091	0.012

Environmental tobacco smoke at home (score 1–4)^2-151
	1	−0.022	0.466		−0.072	0.056
	2	−0.025	0.409		−0.069	0.072
	3	−0.023	0.435		−0.067	0.079

Environmental tobacco smoke at other places (score 1–4)^2-151
	1	−0.047	0.170		−0.071	0.100
	2	−0.047	0.178		−0.061	0.168
	3	−0.045	0.191		−0.059	0.181

Total environmental tobacco smoke (score 3–12)^2-151
	1	−0.037	0.012		−0.060	0.002
	2	−0.041	0.007		−0.058	0.003
	3	−0.041	0.009		−0.057	0.004

Environmental tobacco smoke time/day (h)
	1	−0.027	0.006		−0.029	0.018
	2	−0.031	0.002		−0.028	0.028
	3	−0.031	0.003		−0.028	0.032

Serum cotinine (ng/ml)
	1	0.009	0.669		0.002	0.924
	2	0.009	0.647		0.003	0.816
	3	0.011	0.592		0.008	0.757

↵2-150 Adjusted for (1) sex, age, and height; for (2) sex, age, height, deprivation score, and total energy intake; and for (3) sex, age, height, deprivation score, total energy intake, and respiratory symptoms.
↵2-151 Range of scores of exposure.