s *n* = 0000Early initiators^a^Later initiators^b^Never smokersFormer smokersCurrent smokersFormer smokersCurrent smokers*n* = 0000 (00 %)*n* = 00 (0 %)*n* = 000 (00 %)*n* = 000 (0 %)*n* = 000 (00 %)Sociodemographic factors (%)