Survival rate as an index in evaluating cancer control

A WHO/IARC Expert Committee on Cancer Statistics (1979) reported that it is of increasing importance to make comparisons of survival experience between countries. Unfortunately, there may be insufficient uniformity between different regions with regard to the criteria or classifications used and to registry policy and methods. The study of time trends in survival is complicated by changes in the degree of case reporting to registries, by the increasing number of cancer patients found by screening programmes, and by changes over time in definitions or coding rules of cancer site, stage, histology and even diagnosis. Such problems are inevitable in the medical field, which is evolving continually. Analysis of such data has, however, made important contributions in the field. Survival rates present problems and limitations; however, the overall results from population-based cancer registries are more representative of the general pattern of survival from cancer than those from hospitals (WHO/IARC Expert Committee on Cancer Statistics, 1979). Interesting though a hospital patient series may be, it should be kept in mind that the real efficacy of a cancer control programme can be judged only from population figures.