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Stephen B. Vardeman 《统计学通讯:理论与方法》2013,42(11):2633-2646
This paper considers the use of independent student data collection and analysis projects in the teaching of engineering statistics and quality control. It describes the possible forms such projects can take, gives some details of their use at Iowa State University, and argues for their effectiveness in improving learning. 相似文献
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Radboud J. Duintjer Tebbens Mark A. Pallansch Konstantin M. Chumakov Neal A. Halsey Tapani Hovi Philip D. Minor John F. Modlin Peter A. Patriarca Roland W. Sutter Peter F. Wright Steven G.F. Wassilak Stephen L. Cochi Jong‐Hoon Kim Kimberly M. Thompson 《Risk analysis》2013,33(4):606-646
With the intensifying global efforts to eradicate wild polioviruses, policymakers face complex decisions related to achieving eradication and managing posteradication risks. These decisions and the expanding use of inactivated poliovirus vaccine (IPV) trigger renewed interest in poliovirus immunity, particularly the role of mucosal immunity in the transmission of polioviruses. Sustained high population immunity to poliovirus transmission represents a key prerequisite to eradication, but poliovirus immunity and transmission remain poorly understood despite decades of studies. In April 2010, the U.S. Centers for Disease Control and Prevention convened an international group of experts on poliovirus immunology and virology to review the literature relevant for modeling poliovirus transmission, develop a consensus about related uncertainties, and identify research needs. This article synthesizes the quantitative assessments and research needs identified during the process. Limitations in the evidence from oral poliovirus vaccine (OPV) challenge studies and other relevant data led to differences in expert assessments, indicating the need for additional data, particularly in several priority areas for research: (1) the ability of IPV‐induced immunity to prevent or reduce excretion and affect transmission, (2) the impact of waning immunity on the probability and extent of poliovirus excretion, (3) the relationship between the concentration of poliovirus excreted and infectiousness to others in different settings, and (4) the relative role of fecal‐oral versus oropharyngeal transmission. This assessment of current knowledge supports the immediate conduct of additional studies to address the gaps. 相似文献
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Kimberly M. Thompson Mark A. Pallansch Radboud J. Duintjer Tebbens Steve G. Wassilak Stephen L. Cochi 《Risk analysis》2013,33(4):647-663
Eradication of wild poliovirus (WPV) types 1 and 3, prevention and cessation of circulating vaccine‐derived polioviruses, and achievement and maintenance of a world free of paralytic polio cases requires active risk management by focusing on population immunity and coordinated cessation of oral poliovirus vaccine (OPV). We suggest the need for a complementary and different conceptual approach to achieve eradication compared to the current case‐based approach using surveillance for acute flaccid paralysis (AFP) to identify symptomatic poliovirus infections. Specifically, we describe a modeling approach to characterize overall population immunity to poliovirus transmission. The approach deals with the realities that exposure to live polioviruses (e.g., WPV, OPV) and/or vaccination with inactivated poliovirus vaccine provides protection from paralytic polio (i.e., disease), but does not eliminate the potential for reinfection or asymptomatic participation in poliovirus transmission, which may increase with time because of waning immunity. The AFP surveillance system provides evidence of symptomatic poliovirus infections detected, which indicate immunity gaps after outbreaks occur, and this system represents an appropriate focus for controlling disease outbreaks. We describe a conceptual dynamic model to characterize population immunity to poliovirus transmission that helps identify risks created by immunity gaps before outbreaks occur, which provides an opportunity for national and global policymakers to manage the risk of poliovirus and prevent outbreaks before they occur. We suggest that dynamically modeling risk represents an essential tool as the number of cases approaches zero. 相似文献
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