Contribution of HPLC mass screening for XXXX to a decrease in mortality.

@entity1 @entity204 @entity521 @entity4304
The aim of this study is the estimation of the contribution of HPLC mass screening for @entity521 to the decrease in @entity204 due to this disease. The mortality rates of @entity4304 (ICD 9, 1940; ICD 10, C74; virtually all the cases of these codes are @entity521 during childhood) at 1-4 years of age in cohorts born in 1979-1984, 1985-1988, and 1989-1992 in the whole of Japan were calculated, using data obtained from the Ministry of Health and Welfare. The numbers of @entity1 screened by HPLC in the cohorts were estimated through the reports of the Ministry of Health and Welfare and the database of the Japanese Society for Mass-screening. The mortality of the cohort born in 1989-1992, in which 77.8% of the live births were screened by HPLC, was 1.73 per 100,000 live births. This is about half of that (3.26) of the cohort born in 1979-1984, in which few @entity1 were screened. On the assumption that cases of the 1985-1988 and 1989-1992 cohorts died according to the mortality rate of the 1979-1984 cohort, the expected numbers of @entity204 were estimated; that for the 1985-1988 cohort was 178.51 (of them, that for the @entity1 screened by HPLC was 39.65), and that for the 1989-1992 cohort was 159.78 (of them, that for the @entity1 screened by HPLC was 124.33). The observed numbers of @entity204 were 145 and 85, respectively. Assuming that non-HPLC methods have no effects and using 2 unknown quantities x (contribution of HPLC) and y (other factors), simultaneous equations (1) 178.51 - 39.65x - 178.51y = 145 and (2) 159.78 - 124.33x - 159.78y = 85 were made. Solving them, x = 0.5041 and y = 0.0757 were obtained. In conclusion HPLC screening targeting @entity1 aged 6 months @entity204 at 1-4 years of age by about 50%.
