Incidence rate ratios of breast cancer (per 10 µg dietary cadmium intake/day) for relevant subgroups.

Abbreviations: IRR, incidence rate ratio; CI, confidence interval.
aAdjusted for educational level (<8 y; 8–10 y; >10 y), smoking status (never; former; current), number of births (0; 1–2; 3–8), age at first birth (years, continuous), HRT status (never; former; current), HRT use (years, continuous), age at menarche (years, continuous), BMI (continuous), height (cm, continuous), physical activity (MET score, continuous) and alcohol intake (yes/no and g/day, continuous).
Adjusted model results are shown.