Table 3

Estimated crude effects (OR and 95% CI) of ETS on the risk of head and neck cancer, by active cigarette smoking

Never smokingEver smoking
CasesControlsORcrude (95% CI)CasesControlsORcrude (95% CI)
ETS
Never3131.06141.0
Ever23462.2 (0.6–8.4)121923.1 (1.1–8.3)
Degree of ETS
Never3131.06141.0
Moderate17401.8 (0.5–7.3)80742.5 (0.9–6.9)
Heavy664.3 (0.8–23.5)41185.3 (1.8–16.1)
P for trend0.00820.0016
ETS at home
Never8281.028321.0
Occasionally9103.2 (1.0–10.4)32351.1 (0.5–2.1)
Regularly9211.5 (0.5–4.5)67392.0 (1.0–3.7)
P for trend0.44830.0264
ETS at work
Never7241.027301.0
Occasionally11172.2 (0.7–6.9)35331.2 (0.6–2.4)
Regularly8181.5 (0.5–5.0)65431.7 (0.9–3.2)
P for trend0.46700.0997
Spouse smoking
No11361.068671.0
Yes270.9 (0.2–5.2)31152.0 (1.0–4.0)