Gender and racial differences in smoking of long/ultra-long and king size cigarettes among U.S. adult smokers, NHANES 1999-2012.

Background Cigarette rod length as a design feature may play a specific role in harm perception and tobacco use. Internal tobacco industry documents have shown targeting of females with long/ultra-long cigarettes. This study assessed trends and differences in smoking of long/ultra-long cigarettes among U.S. smokers aged ≥20 years during 1999 through 2012.