The Mortality and Survival page discusses the fact that, particularly in studies concerning racial differences in cancer outcomes, researchers commonly refer to relative differences in survival and relative differences in mortality interchangeably, often stating they are analyzing one relative difference while in fact analyzing the other, but without recognizing that the two relative differences tend to change in opposite directions as overall survival rates change or that more survivable conditions tend to show larger relative differences in mortality but smaller relative differences in survival than less survivable conditions. Several of the tables on that page illustrate the pattern whereby the rarer an outcome the greater tends to be the relative difference in experiencing it and the smaller tends to be the relative difference in avoiding it. These include Table N1, which presents an example where localized cancer shows a smaller relative difference in survival but larger relative difference in mortality than regionalized cancer. Table 1 below present similar data on five-years survival/mortality for nine types of cancer according to three stages (local, regional, distant) based on Figure 4 of the American Cancer Society’s Cancer Facts and Figures for African Americans 2013-2014. The final column also shows the EES, for estimated effect size, which is a measure of disparity theoretically unaffected by the prevalence of an outcome (as discussed on the Solutions subpage of Measuring Health Disparities page).
Table 1. White and black five-year survival rates by type of cancer and stage with ratio of white survival rate to black survival rate and black mortality rate to white mortality rate and estimate effect size (from American Cancer Society data) [refb4127a2]