首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 671 毫秒
1.
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   

2.
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   

3.
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 MEDLINE. 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 formulation. 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   

4.
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   

5.
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   

6.
MEDLINE and MeSH     
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   

7.
Evaluation of a program to teach health professionals to search MEDLINE   总被引:1,自引:0,他引:1  
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   

8.
A survey of users of PsycLIT and MEDLINE on CD-ROM was performed at an academic medical library. The questionnaire was designed to gather information about the user population, satisfaction of the users, the assistance needed to use the systems, and the type of searches being performed. The majority of users were graduate students in the schools of medicine, nursing, and pharmacy. In general, users were satisfied with the performance of the systems. Assistance from a librarian, printed documentation, or another patron was required by 85% of users, and they were generally satisfied with this assistance. Most searches were performed to obtain information on a subject. The results were remarkably similar for both databases.  相似文献   

9.
MEDLINE (MEDLARS-ON-LINE) is the new on-line, interactive bibliographic searching system which was recently developed by the National Library of Medicine. The system provides users with lists of bibliographical citations and other information from a three-year file of over 1,250 biomedical journals. A survey testing user reactions was conducted at the University of Virginia Medical Library. The results of the survey are based on replies by 246 users who requested one or more MEDLINE searches between September 1972 and March 1973. The findings indicate that over 93% believe that MEDLINE is a substantial improvement over the traditional methods of searching through the printed indexes. These respondents also stated that the results of MEDLINE searches had assisted them in their clinical or research work, or both. Asked whether they would continue to use MEDLINE after the imposition of user charges on July 1, 1973, about 75% said that they would. The remaining 25% expressed some reservations and doubts. The survey gives reason to believe that with the imposition of user charges the use of MEDLINE will decline.  相似文献   

10.
A survey of users of PsycLIT and MEDLINE on CDROM was performed at an academic medical library. The questionnaire was designed to gather information about the user population, satisfaction of the users, the assistance needed to use the systems, and the type of searches being performed. The majority of users were graduate students in the schools of medicine, nursing, and pharmacy. In general, users were satisfied with the performance of the systems. Assistance from a librarian, printed documentation, or another patron was required by 85% of users, and they were generally satisfied with this assistance. Most searches were performed to obtain information on a subject. The results were remarkably similar for both databases.  相似文献   

11.
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   

12.
OBJECTIVE: The purpose of this study was to evaluate the efficacy of a decentralized intranet access in each medical department as opposed to centralized unique MEDLINE access in the medical library. DESIGN: A two-phase questionnaire to evaluate MEDLINE use was given to junior and senior physicians at Rouen University Hospital (RUH). Phase I (August-October 1996) corresponded to a time period when centralized access was the only means of access available and phase II (August-October 1997) to a time period following the introduction of decentralized intranet access. RESULTS: A total of 168 physicians filled out at least one phase of the questionnaire, among whom 123 (73%) filled out both phases. Use of MEDLINE significantly increased in 1997 (average of 10.2+/-1.1 searches in three months) versus 1996 (average of 4.9+/-0.7 searches in three months, P<0.0001). The aim of searches changed, becoming significantly more care oriented in phase II (P<0.0001). The number of searches performed by the physicians alone increased (P<0.0001) and searches performed by the librarian decreased (P<0.0001) in phase II. The method of searches also changed, as searches by author (P< 0.0001), by journal (P = 0.0042), and by free word (P = 0.0027) increased in phase II. Knowledge of the following concepts of MEDLINE significantly increased: explosion (P<0.0001), scope note (P<0.0001), Abridged Index Medicus (AIM) journals (P<0.0001), Medical Subject Headings (MeSH) qualifier (P<0.0001), and focus (P<0.0001). CONCLUSION: A decentralized intranet access to MEDLINE increased the number of searches and knowledge of this bibliographic database. MEDLINE intranet access modified the purpose and the methods of searching.  相似文献   

13.
This study compares the results of subject searching in two online catalog systems, one system with authority control, the other without. Transaction logs from Library A (no authority control) were analyzed to identify searching patterns of users; 885 searches were attempted, 351 (39.7%) by subject. One hundred forty- two (40.6%) of these subject searches were unsuccessful. Identical searches were performed in a comparable library that had authority control, Library B. Terms identified in "see" references at Library B were searched in Library A. One hundred five (73.9%) of the searches that appeared to fail would have retrieved at least one, and usually many, records if a link had been provided between the term chosen by the user and the term used by the system.  相似文献   

14.
The paper reviews the highlights of a four-week trial period (November 19-December 18, 1970) during which the Medical Library of the University of Virginia experimented with a new remote-access bibliographical control and retrieval system via its TWX machine. The system, called AIM-TWX, was sponsored by the Lister Hill National Center for Biomedical Communications and utilizes a timeshared IBM 360/67 computer in Santa Monica, California. Citations from 109 clinically-oriented journals from 1966 to date, including those currently included in the Abridged Index Medicus, may be retrieved either on- or off-line.Various aspects of this service are described, including problems of staffing, training, and record keeping, as well as the role of the MeSH vocabulary which is the principle "language" of the man-computer dialog.The statistical results indicated that the system was used for approximately 200 minutes on nineteen days and that an average of sixteen searches were run on any given day, or about 4.6 searches per hour of use. In spite of an inexperienced staff who had little knowledge of the MeSH vocabulary and whose training schedule was limited to one four-hour session, the experiment was highly successful in terms of searches and citations.At the end of the period, 298 searches had been run for 114 requestors, and 5,343 citations had been produced. Only fifty-five searches yielded no citations. The experiment generated a great deal of excitement and interest among the staff of the Library and of the Medical Center. Moreover, a large number of medical practitioners in large and small communities of Virginia participated in this experiment, indicating that there exists a great demand for this type of literature searching which AIM-TWX is able to provide with great rapidity.  相似文献   

15.
The Alfred Taubman Medical Library at the University of Michigan has offered instruction in online literature searching to third-year pharmacy students as a component of the course "Drug Information and Scientific Literature Evaluation" since 1983. In the spring of 1989, a follow-up study was conducted to assess the impact of instruction on four classes of graduates. Of a pool of 151 graduates, 90 (60%) responded to a mailed questionnaire on their use of information and computerized literature searching. The respondents were divided into four subgroups: end-user searchers, users of intermediaries, end users who used intermediaries, and those who did not use computerized literature search systems. Seventy-two percent of the respondents used some type of computerized literature searching, and 42% performed their own searches. The four subgroups differed in general computer use, familiarity with MEDLINE search terminology, information use, reasons for using or not using literature searching, and characteristics of searches (i.e., type, time frame, amount, and frequency). Training in end-user search systems appears to have had an impact on the continued use of computerized literature searching several years after the formal educational program.  相似文献   

16.
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   

17.
An analysis of requests for CD-ROM MEDLINE* searches from June to December 1987 at the Medical Library, Chulalongkorn University, was performed. Requests were received from eighty-two places, in Bangkok and the provinces; 97.8% were from government organizations. MEDLINE on CD-ROM was available from 1982 to date. Most users requested searches covering the previous five or six years. Users were surveyed regarding the service: just over 87% found the service user-friendly. In addition, users suggested that the library conduct search training programs, and more than half of the users noted that a single work station could not meet the search load.  相似文献   

18.
19.
Investigation of end-user searching at the New York Hospital-Cornell University Medical Center (NYH-CUMC) revealed that 8% of the physicians surveyed were end users, 63% were interested in learning to search, and 29% were not interested. When training sessions were offered at the Burke Rehabilitation Center, an affiliated institution, 50% of the medical staff attended at least one class, but only 7% of the total staff became frequent searchers. Analysis of the precision and recall ratios of searches conducted by five end users at HYH-CUMC indicated that the best results were obtained by end users who had been taught to search by experienced librarian-searchers. The quality of end user searches did not appear to be affected by the "friendliness" of the systems used, the frequency of searching habits, or the length of time that an end user had been searching.  相似文献   

20.
Investigation of end-user searching at the New York Hospital-Cornell University Medical Center (NYH-CUMC) revealed that 8% of the physicians surveyed were end users, 63% were interested in learning to search, and 29% were not interested. When training sessions were offered at the Burke Rehabilitation Center, an affiliated institution, 50% of the medical staff attended at least one class, but only 7% of the total staff became frequent searchers. Analysis of the precision and recall ratios of searches conducted by five end users at HYH-CUMC indicated that the best results were obtained by end users who had been taught to search by experienced librarian-searchers. The quality of end user searches did not appear to be affected by the "friendliness" of the systems used, the frequency of searching habits, or the length of time that an end user had been searching.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号