Table 1 Characteristics of eligible patients and participating patients
Age (y)MalesFemalesχ2p Value
Eligible (n)Investigated (n (%))Eligible (n)Investigated (n (%))
40–49313253 (76.7)418407 (97.4)2.7080.099
50–59272252 (92.6)371358 (96.5)0.0890.766
60–69162126 (77.8)217206 (94.9)1.4940.222
70–79159111 (69.8)203186 (91.6)2.6290.105
⩾806122 (36.1)7439 (52.7)1.0820.298
Total967764 (79.0)12831196 (93.2)6.7520.009
Current smokers301 (39.4)279 (23.3)30.140.0001
Ex-smokers286 (37.3)202 (16.9)60.650.0001
Never smokers177 (23.3)715 (59.8)100.70.0001
  • χ2 test and p values regarding age categories refer to differences between the eligible versus the investigated groups. χ2 test and p values regarding smoking status refer to differences between men and women.