Control of Breast Cancer Through Mass Screening

To the Editor.— In the article entitled "Control of Breast Cancer Through Mass Screening" by Dr Philip Strax (235:1600, 1976) there is an error. In describing the original mass screening program for the detection of early breast cancer carried out by the Health Insurance Plan of Greater New York, the statement is made that "31,000 with breast cancer were matched with 31,000 without prior history of breast cancer." The 31,000 women entered into the "study" group did not have breast cancer. This group of 31,000 women were offered annual screening for breast cancer detection, as described in the original reports of Dr Strax and his group. 1 They were then compared with the "control" group, who were not regularly screened for breast cancer. I would like to take issue with the use of the word "control" in the title of this article. There is nothing in the article that increases