ABSTRACT
The main task of the epidemiologist is to discover variables which are always or nearly always found in conjunction with a disease in which he is interested. Quite a curious selection of variables has been found to be associated with lung cancer. Smoking of cigars and of pipes does not seem to be associated with lung cancer to anything like the same extent, the whole argument implicating smoking and lung cancer has been erected and there can be no doubt any longer that there is a statistical association between smoking and lung cancer. While lung cancer has had most of the limelight as far as smoking is concerned it is by no means the only disease that is implicated in connection with smoking. The association with smoking seems to be clear only in middle age, and various other factors, such as sedentary occupation, indulgence in fatty foods and mental strain have been suggested to increase liability to coronary thrombosis.
