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A procedure for a large scale harmonization of assessment systems is delineated. The data collected for the two E.U. co-funded projects STAR and AQEM have been used as a benchmark dataset against which a test dataset derived from Italian standard monitoring programs was compared. A central step in the procedure adopted is the calculation of Intercalibration Common Metrics (STAR_ICMs). For both the benchmark and test datasets, six metrics were calculated, normalized and averaged to obtain an ICM index. The median values obtained for this index within each of the High and Good status classes, as defined within the STAR/AQEM dataset, were compared to the classes defined by the National method applied in Italy before WFD approval. The process of harmonization involved the re-positioning of the boundaries between Italian method quality classes until no more differences were found with the values observed in the STAR/AQEM samples. The re-setting of the Italian assessment boundaries by a step-by-step procedure lead to comparable STAR_ICM index values in the two datasets. Within this example, small refinements of the boundaries between high/good and good/moderate status were sufficient to harmonize the Italian assessment quality classes to the benchmark classification. Once a benchmark dataset is agreed among different countries, the procedure outlined can be easily applied to compare and harmonize assessment systems within and outside Europe. The main scientific and practical advantages of the procedure are listed and commented, especially facing the next steps of the Water Framework Directive Intercalibration process. 相似文献
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Karen Filkins M.D. F.A.C.O.G. Joseph Russo Thomas Brown Susan Schmerler Bernard Searle 《黑龙江环境通报》1984,4(3):223-226
Thirty-one genetic amniocenteses involving multiple gestations were performed in the genetics unit between 1976 and 1982. Three sets of triplets were included. Precise locations of the sacs were determined using real-time ultrasonography and successful sampling of all sacs was accomplished. Spontaneous abortions occurred in two normal twins and one normal triplet gestation. Two therapeutic abortions were performed for fetal abnormalities. Two cases of discordance for trisomy 21 (one twin and one triplet) were allowed to continue; the twin case terminated at 25 weeks' gestation with neonatal deaths and the triplets are alive and well. 相似文献
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