This is critically important because of the enormous contribution of tobacco use to cancer in the decades after 1940. Most recently, a study published in the Journal of the National Cancer Institute linked smoking to colon cancer-a previously unrecognized connection. The evidence seems to indicate that the artificial separation of smoking-related and other cancers created by the authors are indeed meaningless. Incidence vs. Mortality Davis and her co-authors make clear that their analysis of cancer data relates primarily to incidence. The distinction between incidence and mortality may, however, be lost on lay readers.
Mortality refers to deaths from cancer.
Incidence, on the other hand, refers merely to the number of new cases diagnosed. Cancer of the breast and prostate both illustrate that point. Both have increased in incidence without any correspondingly large change in mortality. The authors acknowledge that coronary heart disease has been declining significantly in recent decades. However, they do not adequately consider the effects of competing causes of death.