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Jane Harrison 《Health information and libraries journal》1997,14(1):33-42
Thepractice of evidence-based health care requires that information on methodology be identifiedfrom databases such as MEDLINE. Up until this year there have been no designated medicalsubject headings (MeSH) for evidence-based health care. ‘EVIDENCE-BASEDMEDICINE’ appears as a MeSH term from 1997. The absence of designated MeSH forthis concept prior to 1997 provides a challenge to the searcher. This paper describes the creationof a MEDLINE search strategy to retrieve articles on the methods of evidence-based health carepublished prior to the introduction of the new term, where an optimal combination of free-textand MeSH terms is required to identify relevant material. The study examines both free-text andsubject heading searching and attempts an optimal balance of sensitivity and specificity. It beginsby examining separate free-text and subject heading searches. Sensitivity of the subject headingsearch was 33% and specificity 80%, while the free-text search produced asensitivity of 50% and a specificity of 67%. The final strategy, combining bothapproaches, was more successful with sensitivity reaching between 82 and 90% andspecificity 83%. It is therefore possible to devise a search strategy to retrieve articles on themethods of evidence-based health care with relatively successful rates of sensitivity andspecificity. The limitations of MEDLINE, however, necessitate the use of additional approachesin identifying articles on the methods of evidence-based health care. 相似文献
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Gill Needham Jane Holdsworth Denise Miles 《Health information and libraries journal》1991,8(3):170-171
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Emily Myers 《Journal of Personnel Evaluation in Education》1993,7(1):67-79
Conclusion Supervision, the most prevalent of the control mechanisms studied, was used in all of the schools to varying degrees. The frequency of superintendent visits fluctuated between a high of almost every day, in the case where the superintendent and the principal shared the same facility, to two times a year. Superintendents did visit schools without formal sessions with the principals. Several principals described their superintendents' visits as informal walk-throughs. District size did not influence the frequency of supervision by the superintendents. Schools in both large and small districts received roughly the same number of visits. Ninety-two percent of the principals received a medium or high number of visits. In some schools, particularly unit districts composed of grades kindergarten through 12, principals were evaluated by associate superintendents for secondary education. Central office personnel usually visited several times each month. Principals from large districts received fewer visits from central office staff than did principals from medium or small districts. Most principals perceived the visits by their superintendents and central office personnel as nonthreatening. When superintendents and central office administrators visited schools, they added to the system of control by collecting information about all aspects of schooling, including the climate. In general, principals perceived supervision as light, and felt that schools and principals were afforded considerable autonomy.Vanderbilt University 相似文献
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Jane Dorner 《Instructional Science》1992,21(1-3):5-14
Last year 1279 professional authors completed a lengthy questionnaire on their use of, and attitudes towards, technological tools for writing and publishing. The data were analysed quantitatively, by examining the most frequent responses to items on the questionnaire, and qualitatively, by looking closely at details illuminating the relationship between authors and publishers. The results, for present purposes, are divided into three broad bands of interest: first, what types of writing software authors are currently using; second, what the implications of using authors' disks in the publication chain are; and third, how technology alters perceptions of the copy as a unit of sale. Findings suggest that though authors are operating at basic levels, they have embraced technology with more enthusiasm than their publishers. The challenge facing those involved in books is to make provision for presenting and displaying work in electronic form: to improve contracts and licensing agreements, and to disseminate information on technology to authors.Funded by the British National Bibliography Reseach Fund.© Jane Dorner, 1991 相似文献
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Zuckerman: Scientist Extraordinary by Bernard Donovan BioScientifica, Bristol, 2005, 555pp. ISBN 1‐901978249 £24.95 Negotiating licences for digital resources by Fiona Durrant Facet Publishing, 2006, ISBN 1 85604 586 2 Metadata for Information Management and Retrieval By David Haynes Facet Publishing, 2004, ISBN 1 85604 4890 相似文献