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The consensus is that, in spite of a reluctance in Washington to undertake any drastic reform of the health care financing and delivery system, the changes that are already in place in individual organizations and that are in place or being contemplated at the state level are certain to make the health care system of tomorrow very different from that of today. Physician executives can play an important role in the transition that will be required, but they will have to use a flexible, especially nondogmatic approach if they wish to cope successfully in this increasingly whirling environment. For such physicians, the author says, the opportunities, though unknown, are enormous.  相似文献   
94.
"This study addressed the problem of the Moroccan immigration into Spain within the context of South-North movements, focusing on analyzing provisional data from the last immigrant regularization in the country completed during the end months of 1991."  相似文献   
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The World Health Organization (WHO) diagnostic criteria for diabetes mellitus were determined in part by evidence that in some populations the plasma glucose level 2 h after an oral glucose load is a mixture of two distinct distributions. We present a finite mixture model that allows the two component densities to be generalized linear models and the mixture probability to be a logistic regression model. The model allows us to estimate the prevalence of diabetes and sensitivity and specificity of the diagnostic criteria as a function of covariates and to estimate them in the absence of an external standard. Sensitivity is the probability that a test indicates disease conditionally on disease being present. Specificity is the probability that a test indicates no disease conditionally on no disease being present. We obtained maximum likelihood estimates via the EM algorithm and derived the standard errors from the information matrix and by the bootstrap. In the application to data from the diabetes in Egypt project a two-component mixture model fits well and the two components are interpreted as normal and diabetes. The means and variances are similar to results found in other populations. The minimum misclassification cutpoints decrease with age, are lower in urban areas and are higher in rural areas than the 200 mg dl-1 cutpoint recommended by the WHO. These differences are modest and our results generally support the WHO criterion. Our methods allow the direct inclusion of concomitant data whereas past analyses were based on partitioning the data.  相似文献   
97.
Using the 1980 and 1990 Public Use Microdata Samples, we find that labor market outcomes associated with English proficiency vary with respect to gender. For example, a synthetic cohort analysis provides evidence of gender-related differences in Hispanic workers' English skill acquisition. Moreover, we observe that Hispanic women face a lower English deficiency earnings penalty that rises more sharply with education than the penalty obtained by their otherwise similar male peers. Finally, English fluency appears to serve as a stronger occupational sorting mechanism for women than men. ( JEL J3, J1)  相似文献   
98.
The purpose of this article is to outline the contrasts between the traditional AMC and an organization oriented toward the delivery of population-based managed care. Academic medical centers differ from one another considerably in the extent to which they serve as quaternary care community resources, the degree to which they emphasize primary care in training and care delivery, and the amount of research undertaken. Nor is there a single organizational structure for managed care; successful managed care is practices in IPAs, multispecialty groups, PHOs, and staff-model HMOs. Nonetheless, the contrasts outlined here between AMCs and managed care organizations (MCOs) are valid in most cases.  相似文献   
99.
The Chittagong Healthy City Project was carried out in late 1994 in Chittagong, Bangladesh. This paper presents findings of an evaluation of the project based upon internationally generated process indicators related to the institutional aspects of the project. The following issues are discussed with regard to project implementation: the institutional organization of local authorities, institutions' conceptual understanding of the project, formal insertion of the project into public authorities' activities, institutional leadership of the project, central-local relations, the lack of interministerial coordination, the project's office, international projects, and community organization. Giving consideration to these issues may help program planners detect problems in forthcoming projects prior to their implementation.  相似文献   
100.
SupposeL(X) is the law of a positive random variableX, andZ is positive and independent ofX. Admissible solution pairs (L(X),L(Z)) are sought for the in-law equation $\hat X \cong X o Z$ °Z, where $L\left( {\hat X} \right)$ is a weighted law constructed fromL(X), and ° is a binary operation which in some sense is increasing. The class of weights includes length biasing of arbitrary order. When ° is addition and the weighting is ordinary length biasing, the class of admissibleL(X) comprises the positive infinitely divisible laws. Examples are given subsuming all known specific cases. Some extensions for general order of length-biasing are discussed.  相似文献   
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