Table 3.

The association between wood-burning fireplace and/or stove presence and usage and incident lung cancer, stratified by smoking status¹

	Never smoker				Ever (current or former) smoker
	N cases	HRadj	95% CI	p-trend	N cases	HRadj	95% CI	p-trend
Presence of wood-burning stove/fireplace
No (ref)	6	--	---		107	1.00	---
Yes	52	--	--		167	1.14	0.89 - 1.48
Used wood as a source of fuel
No (ref)	28	1.00	---		154	1.00	---
Yes	30	1.62	0.95 - 2.75		120	1.38	1.08 - 1.77
Annual wood-burning fireplace/stove use
No fireplace/stove or zero use (ref)	20	1.00	---	0.08	135	1.00	---	0.003
1-29 days used/year	21	1.64	0.87 - 3.10		63	0.99	0.73 – 1.35
At least 1 month used/year	17	1.99	1.02 – 3.89		76	1.54	1.15 – 2.07

¹Adjusted for race/ethnicity (NH black, NH white, Hispanic/other), education (HS or less, some college, Bachelors or above), urban status at longest-lived residence (urban, suburban, rural/small town), marital status (single, married, previously married), income status (<$50,000, $50,000-$99,999, $100,000+), total years exposed to environmental tobacco smoke P-for-heterogeneity (used wood as fuel source) = 0.64; p-for-heterogeneity (annual wood-burning fireplace/stove usage) = 0.40