The methods used to prove an increase in lung cancer are fallacious, because they have not taken into consideration alterations in the standards by which this supposed increase has been measured. Thus the age and sex distribution and illness of the patients admitted to hospitals, or coming to autopsy, or coming to autopsy with some type of cancer, (the 3 standards most com-monly used to measure increase in lung cancer) may differ widely during the 2 periods of time under comparison, and will be influenced by such factors as (1) alteration in age and sex distribution in the general population, (2) disappearance of infectious diseases, (3) available number of hospital beds, (4) desirability of patient as teaching material, (5) desire of attending physician for autopsy to elucidate diagnosis, (6) earlier confirmation of diagnosis by biopsy or surgical specimen, (7) improvement in cures in other types of cancer reducing their proportion in cancer autopsies, etc. Even with all these factors controlled, were that possible, it would be only the fraction of lung cancer cases that is actually diagnosed that would be showing an increase; there is yet no way of knowing whether the total number of lung cancer cases is increasing relatively or absolutely.