Five-year prostate cancer survival rates are higher in the United States than in Britain but, according to Howard Parnes of the National Cancer Institute, this is largely a statistical illusion. Americans are screened for the disease earlier and more systematically than Britons. If you are detected with prostate cancer symptoms at age 58 in year one of a disease that takes fifteen years to kill you, your chances of surviving another five years (until the age of 63) are obviously much higher than if your cancer is detected in year eleven, at the age of 68. Both Anderson and Parnes say that it is impossible, on the basis of the available data, to conclude that Americans have a significantly better chance of surviving prostate cancer than Britons.