Table 1.

Subject characteristics of the ESCC cases and controls

VariableCasesControlsP
Total n7461,373
Age, mean (range)63.6 (25-89)55.2 (24-90)<0.001
Gender, n (%)
    Male380 (50.9)700 (51.0)1.0
    Female366 (49.1)673 (49.0)
Ethnicity, n (%)
    Turkmen281 (37.7)811 (59.0)<0.001
    Turk304 (40.7)322 (23.5)
    Persian114 (15.3)133 (9.7)
    Sistani28 (3.7)79 (5.8)
    Balouch9 (1.2)19 (1.4)
    Kurd10 (1.3)9 (0.6)
Ever smoker, n (%)
    Yes200 (27.9)339 (25.0)0.14
    No516 (72.1)1018 (75.0)
Ever opium user, n (%)
    Yes158 (29.1)239 (20.2)<0.001
    No382 (70.9)943 (79.8)