A case-control study was made of the possible synergetic effect of smoking and alcohol drinking on pulmonary tuberculosis. Analysis of the results of 854 interviews showed that there is little interactive effect in the multiplicative sense (synergism) between these factors and pulmonary tuberculosis. It is suggested that the habit of smoking may be related to pulmonary tuberculosis only through its association with that of alcohol drinking.
Tuberculosis, pulmonary; Epidemiology; Alcoholic beverages; Smoking