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171.
This study examines the impact of mandatory seat belt laws on fatal and incapacitating injury rates in the states. Annual data for all 50 states for the period 1975-1991 are used. Pooled time series analysis is employed. The general conclusion that emerges from this analysis is that seat belt laws significantly impact state fatal injury rates. Primary enforcement and all-seat coverage provisions appear to be particularly effective in reducing fatality rates.  相似文献   
172.
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   
173.
174.
The need for long-term care is driven both by the growth of the elderly population and changes in the age relations of morbidity, disability, and mortality. Data show these relations changed in the U.S. elderly population from 1982 to 1989. Chronic disability prevalence declined between the 1982 and 1989 U.S. National Long Term Care Surveys. Among those impaired, many persons using personal assistance to meet their needs shifted to the use of assisted housing and special equipment. The relation of these trends to other changes--such as the increasing educational level of the elderly population--is examined to estimate how future changes in disability and morbidity may affect the demand for long-term care. Disabilities at specific times as well as their transition rates were examined to determine how long individuals need long-term care. The analyses suggest that, while the amount of long-term care services needed will increase rapidly, the types and amounts of services used by the U.S. elderly population will undergo significant change.  相似文献   
175.
In examining various ways of thinking about the development of long-term care policy for the baby-boom cohorts, this article discusses the importance of basing long-term care policy discussions on a recognition of social and economic trends, as well as on the informal exchanges of care that occur over life and the diversity within the baby-boom cohorts. The implications of two ways of thinking about challenges posed by the aging of baby boomers--the generational equity/crisis perspective and the generational investment/gradual adjustment perspective are also discussed. It is suggested that the generational equity perspective is consonant with proposals to expand private savings for long-term care contingencies and private long-term insurance and, secondarily, with proposals to expand means-testing for benefits. The second perspective is more consistent with proposals to create new universal services through a traditional social insurance approach, or through a block grant such as the one discussed in the context of the Clinton health care reform plan.  相似文献   
176.
Statistics in epidemiology: the case-control study   总被引:1,自引:0,他引:1  
This article presents a general review of the major trends in the conceptualization, development, and success of case-control methods for the study of disease causation and prevention. "Recent work on nested case-control, case-cohort, and two-stage case control designs demonstrates the continuing impact of statistical thinking on epidemiology. The influence of R. A. Fisher's work on these developments is mentioned wherever possible. His objections to the drawing of causal conclusions from observational data on cigarette smoking and lung cancer are used to introduce the problems of measurement error and confounding bias."  相似文献   
177.
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   
178.
Constructionist notions have become commonplace in theoretical discussions of the self, but are seldom translated into consideration of specific social work practice concerns such as ADHD. Explorations of ADHD, on the other hand, typically emphasize a narrow, medically-oriented symptom picture that is devoid of the psychosocial context in which the so-called symptoms emerge. A transactional approach to the understanding of ADHD is advanced. This article promotes a link between constructionism and social work's psychosocial or person-in-environment perspective. Such a perspective supports approaches to the assessment of ADHD that illuminate larger cultural messages and their constraining influence on individual meaning-making. Intervention, conducted at multiple levels, must be geared to the establishment of more hopeful and affirming narratives.  相似文献   
179.
Little documentation exists regarding the functioning of formalized adolescent groups as drug abuse prevention agents. Two studies are described that were conducted at high schools whose students are at high risk for drug abuse. Twenty-one schools were randomly assigned to one of three conditions: (a) standard care, (b) classroom drug abuse education only, or (c) classroom plus school-as-community. Results of the first study indicated that the school-as-community component--which involved weekly meetings and periodic events at seven schools--was implemented as planned, drug abused focused, and perceived as productive in discouraging drug abuse. In the second study, staff in the classroom plus school-as-community condition self-reported involvement in the greatest number of community activities across the school year, compared with staff from the other two conditions. These two studies support the feasibility of formalized groups of high-risk youth to promote drug-free events.  相似文献   
180.
Software which allows interactive exploration of graphical displays is widely available. In addition there now exist sophisticated authoring tools which allow more general textual and graphical material to be presented in computer-based form. The role of an authoring tool in providing a graphical interface to a strategy for solving simple statistical problems in the context of teaching is discussed. This interface allows a variety of resources to be integrated. Specific examples, including the use of dynamic graphical displays in exploring data and in communicating the meaning of a model, are proposed. These ideas are illustrated by a problem involving the identification of the sex of a herring gull.  相似文献   
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