Figure 3 – Odds ratios^a,b of oral and pharyngeal cancer in current smokers by alcohol drinking intensity, for the joint effect of intensity (cigarettes/day) and duration (years) of cigarette smoking, estimated through bivariate spline models. INHANCE consortium.

^a Fitted models included adjustment for age, sex, race, study, education, and alcohol drinking status. The reference category was defined as “Never smokers”, in each strata of alcohol drinking intensity. ^b On the grid, black thicker lines represent knot locations: 32 years of duration for never drinkers, and 12 cigarettes/day and 25 years of duration for heavy drinkers, respectively. Dark grey lines in contour plots indicate iso-risk curves at defined levels of risk.