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Utilization review has been regarded as one of the most promising approaches to the containment of health care costs. We analyzed insurance claims data on 222 groups of employees and dependents for 1984 and 1985 to evaluate the effects of utilization review programs instituted by a large private insurance carrier. The utilization review programs we studied were compulsory; patients who did not follow established utilization review procedures were subject to financial penalties. Controlling for employee characteristics, health care market area factors, and benefit-plan features, we found that utilization review reduced admissions by 12.3 percent, inpatient days by 8.0 percent, hospital expenditures by 11.9 percent, and total medical expenditures by 8.3 percent. When only groups that had relatively high admission rates before adopting utilization review were analyzed, it was found that they had a 34 percent reduction in patient days and a 30 percent reduction in hospital expenditures. The savings-to-cost ratio of utilization review for groups overall was highly favorable--approximately 8 to 1. Private utilization review programs of the type we studied appear to be effective in reducing hospital use and decreasing medical expenditures. This study did not address the possible effects of such programs on the health status of patients.  相似文献   
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Mutations in the PEX gene at Xp22.1 (phosphate-regulating gene with homologies to endopeptidases, on the X-chromosome), are responsible for X-linked hypophosphataemic rickets (HYP). Homology of PEX to the M13 family of Zn2+ metallopeptidases which include neprilysin (NEP) as prototype, has raised important questions regarding PEX function at the molecular level. The aim of this study was to analyse 99 HYP families for PEX gene mutations, and to correlate predicted changes in the protein structure with Zn2+ metallopeptidase gene function. Primers flanking 22 characterised exons were used to amplify DNA by PCR, and SSCP was then used to screen for mutations. Deletions, insertions, nonsense mutations, stop codons and splice mutations occurred in 83% of families screened for in all 22 exons, and 51% of a separate set of families screened in 17 PEX gene exons. Missense mutations in four regions of the gene were informative regarding function, with one mutation in the Zn2+-binding site predicted to alter substrate enzyme interaction and catalysis. Computer analysis of the remaining mutations predicted changes in secondary structure, N-glycosylation, protein phosphorylation and catalytic site molecular structure. The wide range of mutations that align with regions required for protease activity in NEP suggests that PEX also functions as a protease, and may act by processing factor(s) involved in bone mineral metabolism.   相似文献   
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