[Studies of screening, detection and mortality rates in mass screening for uterine cervical cancer in Shimane prefecture].

To assess the value of mass-screening for uterine cervical cancer, we compared data obtained from a "model area" with findings obtained from the whole of Shimane Prefecture. The factors given attention were: Screening ratio, detection ratio and mortality directly related to cancer of the uterine cervix. These data were obtained from 1976-1980. The results are as follows: Screening ratio and mortality rates were 35.7% and 7.8% respectively, in the model area and 8.4% and 11.5% respectively, in Shimane Prefecture. Four years after setting up the "model area", the mortality rate for uterine cervical cancer reached zero. The ratio of cancer detection in the "model area" was 0.204%, that is about twice that in Shimane Prefecture. The ratios of detection of severe dysplasia, carcinoma in situ and infiltrative carcinoma were higher in the "model area" than in Shimane Prefecture. Detection of severe dysplasia and carcinoma in situ was significantly high in the "model area". Therefore, to reduce the mortality rate for cervical cancer, the CAI should be over 350.