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1.
《Medical reference services quarterly》2013,32(3):29-46
Through casual observations, formal consultations, and educational sessions, the authors have identified various indexing features of the National Library of Medicine's Medical Subject Headings (MeSH) that pose challenges to end users while attempting to obtain relevant retrieval when searching MEDUNE. These problematic features include the use of Explodes, Tree structures, subheadings, Text Word vs. subject heading searching, and central concept searching. End-user search software is becoming more sophisticated with an increasing number of choices offered for search strategy fomalation. Methods of instruction to orient the end user to these systems will also have to become more detailed. A review of the literature, that discusses end-user problems with using MEDLINE and MeSH, is included. 相似文献
2.
N S Hewison 《Bulletin of the Medical Library Association》1989,77(4):332-336
The emergence of CD-ROM (compact disc/read-only memory) versions of the MEDLINE database requires experienced MEDLINE searchers to examine assumptions about searching MEDLINE, since some expectations may not be fulfilled by this new technology. When applied to a particular CD-ROM MEDLINE product, the evaluation procedure involves testing assumptions concerning database contents; mechanics of searching; display, print, and download capabilities; and user-friendly features. The extent to which a CD-ROM product preserves and exploits important MEDLINE strengths should be assessed, e.g., the MeSH controlled vocabulary, the designation of major and minor MeSH emphasis, and the use of subheadings. Search software characteristics that affect ease of searching and quality of results also need to be examined, e.g., the ability to truncate search terms and the order of precedence in which Boolean operators are evaluated. A checklist to assist in the evaluation process is presented, including search examples for use in testing search functions. 相似文献
3.
Using EndNote version 7.0, the authors tested the search capabilities of the EndNote search engine for retrieving citations from MEDLINE for importation into EndNote, a citation management software package. Ovid MEDLINE and PubMed were selected for the comparison. Several searches were performed on Ovid MEDLINE and PubMed using EndNote as the search engine, and the same searches were run on both Ovid and PubMed directly. Findings indicate that it is preferable to search MEDLINE directly rather than using EndNote. The publishers of EndNote do warn its users about the limitations of their product as a search engine when searching external databases. In this article, the limitations of EndNote as a search engine for searching MEDLINE were explored as related to MeSH, non-MeSH, citation verification, and author searching. 相似文献
4.
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
5.
Nelson JL 《Medical reference services quarterly》1992,11(4):11-21
End users at the University of Southern California (USC) have free access to the last ten years of MEDLINE through a local online system known as USCInfo. Librarians at USC Norris Medical Library provide documentation and offer formal and informal training on the use of the system to search MEDLINE. To assess the educational needs of the end users, 643 searches were analyzed. Although a high proportion (84%) of the searches were judged to be successful, the use of medical subject headings (MeSH) to obtain optimal results was low; only 20% of all successful subject searches employed MeSH. Also, the advanced features of the system were underutilized. While it is promising to learn that many end users are obtaining positive results, methods which will encourage end users improve their retrievals need to be developed. 相似文献
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Lora V. Gault Mary Shultz Kathy J. Davies 《Journal of the Medical Library Association》2002,90(2):173-180
Objectives: This study compared the mapping of natural language patron terms to the Medical Subject Headings (MeSH) across six MeSH interfaces for the MEDLINE database.Methods: Test data were obtained from search requests submitted by patrons to the Library of the Health Sciences, University of Illinois at Chicago, over a nine-month period. Search request statements were parsed into separate terms or phrases. Using print sources from the National Library of Medicine, Each parsed patron term was assigned corresponding MeSH terms. Each patron term was entered into each of the selected interfaces to determine how effectively they mapped to MeSH. Data were collected for mapping success, accessibility of MeSH term within mapped list, and total number of MeSH choices within each list.Results: The selected MEDLINE interfaces do not map the same patron term in the same way, nor do they consistently lead to what is considered the appropriate MeSH term.Conclusions: If searchers utilize the MEDLINE database to its fullest potential by mapping to MeSH, the results of the mapping will vary between interfaces. This variance may ultimately impact the search results. These differences should be considered when choosing a MEDLINE interface and when instructing end users. 相似文献
8.
MEDTUTOR is an interactive, microcomputer-based training package designed to teach medical and health professionals, as well as librarians and information specialists, how to use MEDLINE effectively. The objective of MEDTUTOR is to provide a comprehensive package for teaching the various commands and search techniques required for utilizing the MEDLINE database through the MEDLARS system. MEDTUTOR's menu-driven design allows novice users to learn about the content and use of MEDLINE, such as author searching, text word searching, MeSH indexing, etc., at their own pace and with considerable program feedback. In addition, MEDTUTOR provides the skilled searcher with a way to reinforce or recall previously-learned search techniques without incurring online charges. MEDTUTOR may be used in place of formal training, as a precursor to or as a refresher following formal training, or for review of a particular concept. It provides inexpensive and easily accessible instruction for searching MEDLINE. 相似文献
9.
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
10.
Bronson RJ 《Medical reference services quarterly》1994,13(1):73-80
Locating notes about MeSH subheadings can be one of the most difficult aspects of MEDLINE searching. When used with Medical Subject Headings (MeSH), subheadings serve to limit or define the focus of a heading. National Library of Medicine (NLM) indexers, staff members who enter the MeSH indexing into the database, use subheadings freely. They do follow indexing conventions and savy searchers need to be aware of how to obtain basic subheading information to assist in search formulation. There are a number of methods which may be used in order to view subheading use notes. This column will provide an overview of some alternatives to locating such information. 相似文献
11.
With so many options available for searching MEDLINE on the World Wide Web or as a component of an online service, evaluation criteria are suggested as a means of assisting librarians in determining the positive and negative aspects of alternative MEDLINE sites. A set of searches was utilized to systematically compare MEDLINE sites. Sites evaluated included Avicenna, America Online, HealthGate, PubMed, Medscape, and Physicians' Online. Some features used to evaluate these sites were: default fields; operators (default); access to MeSH; subheadings; stop words protected in MeSH; truncation; and stemming. This article will describe the group process used to arrive at the evaluation criteria, as well as some general conclusions which will help librarians in directing their users to a particular MEDLINE site. 相似文献
12.
This paper investigates the effectiveness of using MeSH® in PubMed through its automatic query expansion process: Automatic Term Mapping (ATM). We run Boolean searches based on a collection of 55 topics and about 160,000 MEDLINE® citations used in the 2006 and 2007 TREC Genomics Tracks. For each topic, we first automatically construct a query by selecting keywords from the question. Next, each query is expanded by ATM, which assigns different search tags to terms in the query. Three search tags: [MeSH Terms], [Text Words], and [All Fields] are chosen to be studied after expansion because they all make use of the MeSH field of indexed MEDLINE citations. Furthermore, we characterize the two different mechanisms by which the MeSH field is used. Retrieval results using MeSH after expansion are compared to those solely based on the words in MEDLINE title and abstracts. The aggregate retrieval performance is assessed using both F-measure and mean rank precision. Experimental results suggest that query expansion using MeSH in PubMed can generally improve retrieval performance, but the improvement may not affect end PubMed users in realistic situations. 相似文献
13.
J G Marshall 《Medical reference services quarterly》1989,8(3):15-26
Although database access has been available via search intermediaries for some time, online services are now encouraging end users to search databases directly. In response to this trend, librarians are taking on new end-user training and support roles. But is this training effort worthwhile? The relationship between online training received and the level of implementation of end-user searching is discussed using survey data from 124 Canadian health professionals (response rate 83%). There was a positive relationship between the number of training events reported and implementation level. Several different kinds of training, in addition to formal courses, were reported by end users. The use of Medical Subject Headings (MeSH) was related to more positive perceptions of online searching which, in turn, predicted higher implementation levels. Variability in the implementation levels of the respondents suggests that end users are a diverse group with different information needs and degrees of searching expertise. Various types of both formal and informal training will continue to be required by end users. 相似文献
14.
F A Brahmi 《Medical reference services quarterly》1988,7(4):47-56
Since 1970, Indiana University School of Medicine Library (IUSML) has traditionally been a high volume online searching institution. The library recently implemented an end user searching program which includes MEDLINE on CD-ROM. The effect of CD-ROM on online end user and mediated searching is discussed. Comparative statistics are provided by category of search service. CD-ROM has had a dramatic lowering effect on online end user searching and has had little effect on mediated searching. IUSML's experience with CD-ROM technology has been a positive one. Trained end users have become IUSML's greatest asset. 相似文献
15.
Colette Hochstein Jeanne Goshorn Florence Chang 《Medical reference services quarterly》2013,32(2):154-163
The Drug Information Portal is a free Web resource from the National Library of Medicine (NLM) that provides a user-friendly gateway to current information for more than 15,000 drugs. The site guides users to related resources of NLM, the National Institutes of Health (NIH), and other government agencies. Current drug-related information regarding consumer health, clinical trials, AIDS, MeSH pharmacological actions, MEDLINE/PubMed biomedical literature, and physical properties and structure is easily retrieved by searching on a drug name. A varied selection of focused topics in medicine and drugs is also available from displayed subject headings. This column provides background information about the Drug Information Portal, as well as search basics. 相似文献
16.
Objective: To determine whether information retrieval might be enhanced by making each component of a structured abstract a separately searchable field. Design: Parallel searches on records arranged so that each abstract could either be searched in its entirety or as a collection of structured fields. Subjects: Records about cardiovascular disease downloaded from MEDLINE and tested against clinical questions derived from a concurrent survey of CD-ROM use in three health science libraries. Intervention: The investigators identified terms used to structure abstracts on MEDLINE and imported the abstracts into an Idealist database prior to searching using keywords from clinical questions. Measurements and main results: recall and precision rates are given for each question in the ‘structured’ and the ‘unstructured’ set of records. Conclusions: Use of structured, rather than unstructured, abstracts improves precision at the ex-pense of recall and places heavier demands upon the searcher’s skill in choosing the correct fields within the abstract to search. Further investigation requires more accurate simulation of MEDLINE software that utilizes features such as MeSH terms, explode, facilities and delimiters. 相似文献
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M A Cahan 《Medical reference services quarterly》1989,8(4):61-79
The latest release of GRATEFUL MED offers medical libraries an opportunity to monitor searching patterns of end users searching the databases of the National Library of Medicine (NLM). A GRATEFUL MED use log records information from each search session. Analysis of the log from a recent beta test program at the Welch Medical Library indicates that most NLM searches occur in the MEDLINE database. Moreover, the study reveals that searchers overlook many user-friendly features of the program. Evaluation of the use log suggests changes for future versions of the program. 相似文献
19.
Melissa Gomis Carole Gall Frances A. Brahmi 《Medical reference services quarterly》2013,32(3):260-271
ABSTRACT The authors of this article analyzed the differences in output when searching MEDLINE direct and MEDLINE via citation management software, EndNote X1®, EndNote Web®, and RefWorks©. Several searches were performed on Ovid MEDLINE and PubMed directly. These searches were compared against the same searches conducted in Ovid MEDLINE and PubMed using the search features in EndNote X1, EndNote Web, and RefWorks. Findings indicated that for in-depth research users, should search the databases directly rather than through the citation management software interface. The search results indicated it would be appropriate to search databases via citation management software for citation verification tasks and for cursory keyword searching. 相似文献
20.
This study analyzes the search behavior of end users who had taken a class in searching MEDLINE on the National Library of Medicine's MEDLARS system. Of the class alumni, 58% obtained passwords. Most of these were still conducting their own searches twelve to eighteen months later. Telephone interviews and search observations indicated that these end users were satisfied with their results and felt they had mastered the basic mechanics of searching. However, appropriate use of explodes and subheadings, as well as locating appropriate search terms, still presented difficulties for them. Further training in these areas may be required. 相似文献