Koong Shin-lan points out that in the US, where the incidence of breast cancer is very high (one in nine women will get breast cancer at some time in their lives), women over 40 years of age are supposed to get tested once every two years, while women over 50 are to be tested each year.
孔憲蘭指出，由於美國乳癌發生率極高（每九名婦女有一人罹患乳癌），因此，四十歲以上的婦女每兩年做一次乳房攝影，五十歲以上婦女，每年做一次。