Figure 5.

Associations between body-mass index and oral, stomach, and lung cancers with effect modification by smoking status

Curves for each cancer type estimated from models with BMI fitted as a spline, interaction terms between smoking status and spline basis, adjusted for age, calendar year, diabetes status, alcohol use, socioeconomic status (index of multiple deprivation), and stratified by sex. p values for effect of BMI in never smokers=0·62 for oral cavity cancer, 0·16 for stomach cancer, and 0·18 for lung cancer. Estimated curves by smoking status for all cancer types are presented in appendix p 10. P_interaction=p value for interaction. HR=hazard ratio.