Comparison of cancer subgroups in SMND patients and controls.

Odds ratios (ORs) adjusted for age, gender and smoking with logistic regression where case numbers were ≥5, and with contingency tables when case numbers were <5. Where one cell contained no values, no ORs were calculated but p-values were calculated with Fischer's exact test. CI: confidence interval, CUP: cancer of unknown primary, GIT: gastrointestinal tract, N: number, NA: not applicable, N-M: non-melanoma.