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151.
Because the item, "How concerned are you about...?" asks respondentsto indicate their level of concern about an issue, some respondentsmay sense it assumes they are concerned or should be concernedabout the issue. Using a filter question to first determineif people are concerned about the issue before asking for theirdegree of concern may help solve this problem. To test thishypothesis, a split-ballot experiment was embedded in a nationalrandom digit dialing telephone survey on food-related issues.For the four items included in the experiment, the group receivingthe filter versions of the questions gave roughly double thepercentages of "not concerned" responses as the group receivingstandard items, and the filter group also gave fewer responsesat the upper end of the response scale. 相似文献
152.
153.
Physicians practicing in large, multispecialty medical groups share an organizational culture that differs from that of physicians in small or independent practices. Since 1980, there has been a sharp increase in the size of multispecialty group practice organizations, in part because of increased efficiencies of large group practices. The greater number of physicians and support personnel in a large group practice also requires a relatively more sophisticated management structure. The efficiencies, conveniences, and management structure of a large group practice provide an optimal environment to practice medicine. However, a search of the literature found no data linking a large group practice environment to practice outcomes. The purpose of the study reported in this article was to determine if physicians in large practices have fewer quality and utilization problems than physicians in small or independent practices. 相似文献
154.
Paul C 《Physician executive》1995,21(10):42-43
Recently, the number of physicians who have been interested in alternative careers has vastly increased. Many physicians express dissatisfaction with clinical practice, but they are uncertain about which nonclinical options are appropriate for them. Pursuing a different career after many years of studying and practicing medicine can seem like an overwhelming task. In this article, the author briefly outlines a decision-making process that can be used in analyzing career options and suggests some careers that have provided challenging opportunities for physicians. 相似文献
155.
The dramatic increase in U.S. cesarean sections over the past two decades has been significantly driven by repeat C-sections. In response to this trend, clinical guidelines recommending vaginal birth after cesarean-section (VBAC) have been promulgated by national organizations. Adherence to these guidelines would reduce the number of repeat C-sections, lower the overall C-section rate, and improve both the quality and the cost of health care. While these guidelines have received professional endorsement, their implementation has been clouded by issues of patient acceptance and provider payment. To examine implementation of these guidelines by health care organizations, the authors surveyed 156 members of the American College of Physician Executives to determine their policies, practices, and attitudes toward VBAC guidelines. Those surveyed generally were medical directors in HMOs, hospitals, and other practice settings. The findings indicate that the health care organizations represented by these physician executives have not consistently implemented VBAC guideline and that they are reluctant to hold physicians, their patients, or hospitals accountable for the financial, utilization, and quality impact of the elective decision ot to pursue appropriate VBACs. We conclude that, even when widely accepted, clinical practice guidelines may be ineffective in reducing the costs or improving the quality of medical care. 相似文献
156.
Cummings KC 《Physician executive》1995,21(10):14-17
The need for physicians in management roles in the health care system has never been greater. And the years ahead will see that need broadened and intensified. To maintain their leadership role in medical affairs in hospitals and other types of health care delivery organizations, physician executives will have to envision provider organizations and systems that have not yet been conceived, let alone developed and implemented. They have to become totally open-minded and futuristic in their thinking. And they will have to help other physicians accommodate this new way of thinking if the medical profession is to continue in a leading role in health care matters. Although numerous factors will have to be anticipated and analyzed by these new physician leaders, the ascendancy of primary care in a managed health care world long dominated by the technical and technological superiority of hospital care will present a particular challenge to the physician executive. 相似文献
157.
Okojie CE 《Journal of social development in Africa》1995,10(1):25-35
Nikrowa is a riverine village located in Ovia North-East Local Government Area of Edo State. This paper examines the relationship between the environment and the health status of women and children in the village. Data used in this essay were obtained mainly in focus groups from a study of women and health service utilization in Nikrowa. Women in Nikrowa farm, fish, collect water and firewood, and process and prepare food. They also bear many children. Their hard physical labor causes them to suffer continuous body aches and pains. Environment-related illnesses such as malaria, measles, dysentery, and diarrhea are prevalent among children. The geographical isolation of Nikrowa limits access to modern health care facilities, so traditional therapies are used to treat prevailing illnesses. It is suggested that women have access to fertilizers in order to improve soil fertility and agricultural yields. Fuelwood and adequate and safe water supplies should be made readily available to women. Moreover, access roads to rural areas should be improved to facilitate transport to modern health care facilities, and rural primary health care facilities should be helped to provide efficient services by providing trained staff and ensuring regular supplies of drugs. 相似文献
158.
"This article examines the probable effects of the North American Free Trade Agreement (NAFTA) on migration from Mexico to the United States, disputing the view that expansion of jobs in Mexico could rapidly reduce undocumented migration. To the extent that NAFTA causes Mexican export agriculture to expand, migration to the United States will increase rather than decrease in the short run. Data collected in both California and the Mexican State of Baja California show that indigenous migrants from southern Mexico typically first undertake internal migration, which lowers the costs and risks of U.S. migration. Two features of employment in export agriculture were found to be specially significant in lowering the costs of U.S. migration: first, working in export agriculture exposes migrants to more diverse social networks and information about U.S. migration; second, agro-export employment in northern Mexico provides stable employment, albeit low-wage employment, for some members of the family close to the border (especially women and children) while allowing other members of the family to assume the risks of U.S. migration." 相似文献
159.
160.
Implementing partial least squares 总被引:2,自引:0,他引:2
M. C. Denham 《Statistics and Computing》1995,5(3):191-202
Partial least squares (PLS) regression has been proposed as an alternative regression technique to more traditional approaches such as principal components regression and ridge regression. A number of algorithms have appeared in the literature which have been shown to be equivalent. Someone wishing to implement PLS regression in a programming language or within a statistical package must choose which algorithm to use. We investigate the implementation of univariate PLS algorithms within FORTRAN and the Matlab (1993) and Splus (1992) environments, comparing theoretical measures of execution speed based on flop counts with their observed execution times. We also comment on the ease with which the algorithms may be implemented in the different environments. Finally, we investigate the merits of using the orthogonal invariance of PLS regression to improve the algorithms. 相似文献