Characteristics of participants by status of fuel use and ventilation for cooking.

Data are mean (SD) unless otherwise indicated. CF-only: only use of clean fuels; V-only: only improved ventilation; Both: both use of clean fuels and improved ventilation; Neither: neither use of clean fuels nor improved ventilation.aThere were nine participants whose data were missing, including two participants in Group Both, one participant in Group CF-only, and six participants in Group Neither.bCalculated for 265 smokers (only one female), including 65 participants in Group Neither, 62 in Group CF-only, 34 in Group V-only, and 104 in Group Both.cBiomass exposure index was defined as the number of years before baseline multiplied by the hours of exposure to biomass for cooking per day.dCalculated for 269 smokers (only one female), including 67 participants in Group Neither, 62 in Group CF-only, 34 in Group V-only, and 106 in Group Both.eThere were ten participants whose data were missing, including five participants in Group Both, one participant in Group CF-only, and four participants in Group Neither.