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991.
M Liebman M A Kenney W Billon A J Clark G W Disney E G Ercanli E Glover H Lewis S W Moak J H McCoy P Schilling F Thye T Wakefield 《The American journal of clinical nutrition》1983,38(1):109-114
Hb, hematocrit, plasma iron, and transferrin saturation were measured in approximately 1000 girls aged 12, 14, or 16 yr in eight southern states. The iron status parameters did not differ significantly among the three age groupings or between menstruating and nonmenstruating girls. Blacks had significantly lower mean Hb (p less than 0.0001), hematocrit (p less than 0.0001), and transferrin saturation (p less than 0.05) levels than whites and a greater proportion of Blacks exhibited low Hb (p less than 0.05) and low hematocrit levels (p less than 0.01). Adjusting for dietary iron intakes and per capita income levels did not adequately account for significant race differences for iron status parameters. These findings support the contention that genetic as well as environmental factors are responsible for the frequently reported Black-white differences in Hb and hematocrit levels. 相似文献
992.
This paper examines how rates of uninsurance for low-income parents have been changing over time and the extent to which expanding coverage to parents through Medicaid and the State Children's Health Insurance Program (SCHIP) could help them. We find that uninsurance rates have been rising for low-income parents, especially those living in poverty, and that Medicaid and SCHIP could greatly reduce uninsurance among parents and would likely increase their access to care. Such expansions would still leave many noncitizen parents uninsured and would require reaching and enrolling families whose children have remained uninsured despite being eligible for public coverage. 相似文献
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M L Kenney 《Clinical chemistry》1987,33(5):725-738
Since 1971, federal laboratory regulations have required that directors of approved laboratories possess earned doctorates. Private accrediting agencies and some states also require doctoral directorship of accredited laboratories. No empirical studies have demonstrated that a director's earned doctorate is necessary to assure laboratory quality. Laboratories in physicians' offices (POLs) are exempt from federal regulation but receive federal reimbursement on the basis of the physicians' medical degree. No empirical studies have demonstrated that unregulated laboratories perform comparably with regulated laboratories. This investigation found no statistically discernible differences in quality when 1983 proficiency test data were used to compare statistically the performance of doctoral- and non-doctoral-directed Medicare-certified independent laboratories in California. When regulated non-doctoral-directed full-service laboratories were statistically compared with unregulated limited service POLs, regulated non-doctoral-directed laboratories consistently demonstrated superior per formance to POLs. Evidently a director's earned doctorate is neither a necessary nor a sufficient condition to assure laboratory performance. Government regulation appears to provide substantial quality assurance in the clinical laboratory field. 相似文献
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