This population-based cross-sectional survey was carried out to determine the prevalence of chronic bronchitis and associated risk factors in a rural area of Kayseri, Central Anatolia, Turkey. Subjects (1,023) aged 20-83 yrs (81.8% of eligible subjects) were interviewed using a modified version of the adult questionnaire compiled by the European Community Respiratory Health Survey. Subjects with 'presence of cough and phlegm on most days during at least three months per year for at least the two previous years' were classified as having chronic bronchitis. According to the criteria used, 138 (13.5%) were classified as having chronic bronchitis. The prevalence was higher in males (17.8%) than females (10.0%). There was no overall significant association between chronic bronchitis and age in males, but, in females, the difference between age groups was important. There was no association between chronic bronchitis and family income, although the prevalence was highest in the low-income group. Subjects who reported childhood respiratory illnesses had a 1.7-fold increased risk of chronic bronchitis compared to those without such a history. The prevalence was much higher among people exposed to biomass fuel combustion and among smokers and exsmokers than among nonsmokers. In multivariate analyses, a significant increase in the prevalence of chronic bronchitis was seen in males, those who had received poor schooling, those reporting childhood respiratory illnesses, and those exposed to biomass fuel combustion and according to smoking habit.