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121.
McGivney WT 《Physician executive》1991,17(1):36-38
Coverage decisions by third-party payers are relying more and more heavily on the conclusions of technology assessment programs about the safety and effectiveness of technologies applied in specific clinical situations. Assessment programs vary markedly in the sophistication and rigor of their methodology. Payers differ as to how such assessment information is integrated into their decision-making processes. Finally, coverage decisions about a specific technology can vary widely across the country. 相似文献
122.
The challenge of world health 总被引:1,自引:0,他引:1
2 development specialists have expounded on the demands world health has placed on public health. Striking declines in infant and child mortality occurred with the advent of biomedical and technical interventions in developing countries after World War II. At the same time, these interventions promoted longer lives by curing and/or treating chronic diseases in developed countries. In the 1970s, however, it was apparent that the hospital based, curative approach could not meet health needs and was very costly. In developed countries, biomedical and social sciences showed that chronic diseases did not occur due to modernization but from unhealthy behaviors, diet, and lifestyle. In fact, in 1975, the US Centers for Disease Control announced that unhealthy lifestyles contributed to 50% of all deaths while the medical system was responsible for only 11%. The US and other developed countries then began to promote healthy lifestyles, and in the 1980s, considerable improvements in health occurred, especially among adults. Developing countries which depended on the Western medical model did not experience health gains in the 1970s. Yet developing countries where health systems concentrated on carrying essential services to all people and promoted basic hygiene and sound dietary practices continued to achieve considerable health gains. In 1978, WHO an UNICEF hosted the International Conference on Primary Health Care in Alma Ata, the Soviet Union to hold these developing countries with community based health systems as models of primary health care (PHC). The 1980s witnessed the spread of PHC especially in the form of child survival which focused on oral rehydration therapy and breast feeding. The biomedical and social sciences are needed to move this health policy and program strategy forward. Governments must see to policies that promote healthy people. Political will is needed to make human welfare a high priority. 相似文献
123.
Recent trends in the process of stratification 总被引:1,自引:0,他引:1
Using the 14 annual cross-sections from the General Social Survey, we specify a "basic model" of attainment and describe the year-by-year fluctuations in its parameters. The results are partially consistent with theories describing the gradual growth of universalistic patterns of stratification and mobility. Under a linear model of educational achievement, we find that the direct effects of race are weakening and the returns to class-based advantages are declining in tandem. The contours of the socioeconomic "gender gap" are also changing in important ways, with the male intercept declining at a rapid pace and the female term registering small and insignificant year-by-year gains. At the same time, the returns to experience and schooling are increasing for men, whereas the corresponding returns for women have remained stable over the 15-year period. This pattern of interaction effects implies that the size of the gender gap varies over time and across different population groups. 相似文献
124.
125.
Prior to the 1980s, managed care was virtually nonexistent as a force in health care. Presently, 64 percent of employees in America are covered by managed care plans, including health maintenance organizations (20 percent) and preferred provider organizations (44 percent). In contrast, only 29 percent of employees were enrolled in managed care plans in 1988 and only 47 percent in 1991. To date, the primary reason for this incredible growth in managed care has been economic-market pressure to reduce health care costs. For the foreseeable future, political pressures are likely to fuel this growth, as managed care is at the center of President Clinton's national health care plan. Although there are numerous legal issues surrounding managed care, this article focuses primarily on antitrust implications when forming managed care entities. In addition, the corporate practice of medicine doctrine, certain tax issues, and the fraud and abuse laws are discussed. 相似文献
126.
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128.
Frank AW 《Second opinion (Park Ridge, Ill.)》1994,20(1):10-18
In attempting to manage their practices efficiently, doctors may not allow seriously ill patients enough time to sort out their feelings and raise important questions. What is at stake here is not information about prognosis and treatments but the very survival of the soul. 相似文献
129.
Evolution strategies (ESs) are a special class of probabilistic, direct, global optimization methods. They are similar to genetic algorithms but work in continuous spaces and have the additional capability of self-adapting their major strategy parameters. This paper presents the most important features of ESs, namely their self-adaptation, as well as their robustness and potential for parallelization which they share with other evolutionary algorithms.Besides the early (1 + 1)-ES and its underlying theoretical results, the modern ( + )-ES and (, )-ES are presented with special emphasis on the self-adaptation of strategy parameters, a mechanism which enables the algorithm to evolve not only the object variables but also the characteristics of the probability distributions of normally distributed mutations. The self-adaptation property of the algorithm is also illustrated by an experimental example.The robustness of ESs is demonstrated for noisy fitness evaluations and by its application to discrete optimization problems, namely the travelling salesman problem (TSP).Finally, the paper concludes by summarizing existing work and general possibilities regarding the parallelization of evolution strategies and evolutionary algorithms in general. 相似文献
130.
Bielefeld W 《Nonprofit management & leadership》1994,5(1):19-36
This article describes mortality patterns for nonprofit organizations in a major U.S. metropolitan area between 1980 and 1988. Twenty percent of the nonprofits in a panel ceased operations during this period. Mortality rates were found to vary widely. In some instances, high mortality was found in parts of the sector that were growing rapidly. Overall, nonprofits that ceased to operate were younger and smaller, used fewer strategies to attract funders, and had less diversified income streams than survivors. These patterns also varied substantially. The results point to the drawbacks of using limited or commonsense information and the necessity of theory-based research. 相似文献