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The National Library of Medicine has had an enormous impact on health information services all over the world. Although NLM is primarily a national institution, it has become an important international resource by responding to requests from the international community. NLM has been influential in three major ways. First, NLM has provided a model for other national and regional health information services. Second, it has been a catalyst, in that MEDLARS and other services it provides formed the nucleus of many regional networks. NLM helped such networks get started by giving advice on how to set up services and build collections and by "training the trainers" on the MEDLARS system. Third, NLM has supported national and regional operations by providing the additional training and materials needed for day-to-day service. 相似文献
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This article reports the results of a survey of literature on measures of library effectiveness. This survey led to the formulation of six criterion concepts (accessibility, cost, user satisfaction, response time, cost/benefit ratio, and use). The advantages and disadvantages of each method of measurement are discussed. Several points which became clear during the analysis are discussed. First, there is a relative lack of concern with the rationale behind the evaluation process, although the results invariably lead to a confused interpretation when there is no clear understanding of the purpose of an evaluation. Second, the total library system is rarely considered; instead, each evaluation criterion is taken in isolation rather than as part of the whole. Third, the library's preservation function has not been considered at all. 相似文献
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