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971.
972.
973.
Searching for patterns in the MeSH vocabulary 总被引:1,自引:0,他引:1
NLM revises its MeSH vocabulary annually to reflect changes in biomedical literature and the health sciences community. This study tested two hypotheses about NLM's MeSH vocabulary. The first is that new terms are added to MeSH when their broader terms have an increased number of postings. One examination compared the number of postings for the broader terms of new and existing terms in the current MEDLINE file; the other compared them over time. No significant statistical difference was found in either case. A second hypothesis--that there is a relationship between the patterns of MEDLINE indexing and searching and the organization of the MeSH tree structure--was tested by comparing the distribution of searched terms in the MeSH trees with the distribution of all terms. It was found that certain trees are searched more often than could be predicted by the overall term distribution, while others are searched less frequently than expected. In summary, (1) new terms cannot be predicted by the increase in postings of existing terms, and (2) searchers' and indexers' use of the terms' tree structure does not correlate with the terms' distribution in the MeSH trees. 相似文献
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975.
S A Hook 《Medical reference services quarterly》1986,5(4):35-40
While many librarians support the concept of end user searching, they fear that large costs will be incurred with the introduction of such a program. This article describes an economical end user training program which was developed at the Indiana University School of Dentistry. End user training at IUSD is fully self-supporting and has been tailored to meet the needs of a very specialized user group. 相似文献
976.
The public's growing interest in health information and the health professions' increasing need to locate health education materials can be answered in part by the new Combined Health Information Database (CHID). This unique database focuses on materials and programs in professional and patient education, general health education, and community risk reduction. Accessible through BRS, CHID suggests sources for procuring brochures, pamphlets, articles, and films on community services, programs at HMOs and hospitals, aspects of coping, and more. CHID is a joint project of six federally funded agencies in the Public Health Service. CHID provides citations with abstracts to major health journals, books, reports, pamphlets, hard-to-find information resources, and to health education programs under way in state and local health departments and other locations. 相似文献
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979.
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David S. Nelson 《Educational Measurement》1994,13(3):29-35
How might empirical j o b analysis give the appearance of science to a flawed public policy? How do “political” factors have an impact on the development of licensure tests? What are areas for future research and for improvement of prevailing practices in licensure and certification testingy? 相似文献