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1.
Background: Systematic review articles support the advance of science and translation of research evidence into healthcare practice. Inaccurate retrieval from medline could limit access to reviews. Objective: To determine the quality of indexing systematic reviews and meta‐analyses in medline . Methods: The Clinical Hedges Database, containing the results of a hand search of 161 journals, was used to test medline indexing terms for their ability to retrieve systematic reviews that met predefined methodologic criteria (labelled as ‘pass’ review articles) and reviews that reported a meta‐analysis. Results: The Clinical Hedges Database contained 49 028 articles; 753 were ‘pass’ review articles (552 with a meta‐analysis). In total 758 review articles (independent of whether they passed) reported a meta‐analysis. The search strategy that retrieved the highest number of ‘pass’ systematic reviews achieved a sensitivity of 97.1%. The publication type ‘meta analysis’ had a false positive rate of 5.6% (95% CI 3.9 to 7.6), and false negative rate of 0.31% (95% CI 0.26 to 0.36) for retrieving systematic reviews that reported a meta‐analysis. Conclusions: Inaccuracies in indexing systematic reviews and meta‐analyses in medline can be partly overcome by a 5‐term search strategy. Introducing a publication type for systematic reviews of the literature could improve retrieval performance.  相似文献   

2.
Background: The Polish Medical Bibliography (Polska Bibliografia Lekarska) contains 350 000 records dating from 1979. These records from the fields of medicine, nursing, dentistry, health care systems and preclinical sciences are from nearly 300 biomedical journals published in Poland. Methods: We systematically searched the Polish Medical Bibliography Part II (1996–2006) CD‐ROM (July 2006) using both English and Polish phrases for randomized trials, manually checked results and, for the trials identified in this way, sought these on medline and embase . Results: Systematic searching identified records of 680 randomized trials from all areas of health care. Nearly 40% of these were not found on either medline or embase . Conclusions: The Polish Medical Bibliography should be of interest to health care information specialists concerned with comprehensive searches for trials.  相似文献   

3.
BACKGROUND: The University of Sofia, Bulgaria, disseminates local biomedical literature (1994 to present) through a free online database, ABS. OBJECTIVES: Our objectives were to systematically search ABS, identify citations to controlled trials and discover what proportion of these studies are to be found on medline. METHODS: We searched using Bulgarian and English phrases; manually selected citations of controlled trials and sought these citations on medline. Results: Using the two languages, we found a total of 628 unique citations, 47 of which seem to be relevant controlled trials (precision 7.48%, 13% of ABS citations were found on medline). The trials in ABS commonly focused on evaluation of care for people with cardiovascular or urological problems. DISCUSSION: ABS is another source of easily accessed trials not readily available elsewhere.  相似文献   

4.
Background: People search medline for trials of healthcare interventions for clinical decisions, or to produce systematic reviews, practice guidelines, or technology assessments. Finding all relevant randomized controlled trials (RCTs) with little extraneous material is challenging. Objective: To provide comparative data on the operating characteristics of search filters designed to retrieve RCTs from medline . Methods: We identified 38 filters. The testing database comprises handsearching data from 161 clinical journals indexed in medline . Sensitivity, specificity and precision were calculated. Results: The number of terms and operating characteristics varied considerably. Comparing the retrieval against the single term ‘randomized controlled trials.pt.’ (sensitivity for retrieving RCTs, 93.7%), 24 of 38 filters had statistically higher sensitivity; 6 had a sensitivity of at least 99.0%. Four other filters had specificities (non retrieval of non‐RCTs) that were statistically not different or better than the single term (97.6%). Precision was poor: only two filters had precision (proportion of retrieved articles that were RCTs) statistically similar to that of the single term (56.4%)—all others were lower. Filters with more search terms often had lower specificity, especially at high sensitivities. Conclusion: Many RCT filters exist (n = 38). These comparative data can direct the choice of an RCT filter.  相似文献   

5.
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   

6.
The performance of adverse effects search filters in MEDLINE and EMBASE   总被引：1，自引：1，他引：0  
Background: Search filters can potentially improve the efficiency of searches involving electronic databases such as medline and embase . Although search filters have been developed for identifying records that contain adverse effects data, little is known about the sensitivity of such filters. Objectives: This study measured the sensitivity of using available adverse effects filters to retrieve papers with adverse effects data. Methods: A total of 233 included studies from 26 systematic reviews of adverse effects were used for analysis. Search filters from medline and embase were tested for their sensitivity in retrieving the records included in these reviews. In addition, the sensitivity of each individual search term used in at least one search filter was measured. Results: Subheadings proved the most useful search terms in both medline and embase . No indexing terms in medline achieved over 12% sensitivity. The sensitivity of published search filters varied in medline from 3% to 93% and in embase from 57% to 97%. Whether this level of sensitivity is acceptable will be dependent on the purpose of the search. Conclusions: Although no adverse effects search filter captured all the relevant records, high sensitivity could be achieved. Search filters may therefore be useful in retrieving adverse effects data.  相似文献   

7.
Objectives: National databases may be useful sources in the production of a systematic review (SR). The aim of this study was to assess the potential benefit of a systematic search in the German database ‘Current Contents Medizin’ (CCMed ). Methods: The study was conducted on the basis of published SRs that included CCMed as a literature source. Eligible SRs were identified through a systematic search in medline , embase and The Cochrane Library. The websites of German Health Technology Assessment agencies were also screened. Citations of primary studies included as relevant in the SRs were extracted and then categorised. Results: The search yielded 52 eligible SRs. A total of 1505 relevant citations were extracted. Seventy‐seven of these articles were published in journals indexed in CCMed . Thirty‐two of the 77 citations were indexed in CCMed , but only eight of the 32 were unique. Of these eight citations, seven were not identified by a systematic search, but by handsearching. Only one unique citation, an observational study, was identified in CCMed by a systematic search. Conclusions: In the production of SRs, a systematic search in CCMed identifies relevant studies only in exceptional cases. Therefore, the routine inclusion of this database in systematic searches does not appear meaningful.  相似文献   

8.
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   

9.
Background: To develop and apply search filters retrieving the scientific output (SO) after 2000 focusing on Public Health (PH) of the new European Union (EU) Member States after the 2004 and 2007 enlargements. Methods: Twelve geographical filters (GFs) were designed and applied to retrieve references added since 2001 in medline (accessed through Pub Med ) and originated in the new EU countries. The PH area was accessed using Medical Subject Heading terms. The filters were evaluated through a manual check and the agreement/non‐agreement percentages were calculated. Results: A number of 99 912 articles revealing the total SO and 6502 articles focusing on PH were retrieved. More than 66% were published abroad and more than 80% in English. The evaluation revealed an average agreement percentage of 98.97%. The results were compared with those obtained by using simple search strategies. Conclusions: Twelve GFs applied to medline retrieved references belonging to twelve countries for a specific period of time. The evaluation of the GFs through the manual check demonstrated effectiveness of these filters. Complementary studies would be advisable to focus on the development of search filters to retrieve complete and accurate information.  相似文献   

10.

Background

The most current objectively derived search filters for adverse drug effects are 15 years old and other strategies have not been developed and tested empirically.

Objective

To develop and validate search filters to retrieve evidence on adverse drug effects from Ovid medline and Ovid Embase.

Methods

We identified systematic reviews of adverse drug effects in Epistemonikos. From these reviews, we collated their included studies which we then randomly divided into three tests and one validation set of records. We constructed a search strategy to maximise relative recall using word frequency analysis with test set one. This search strategy was then refined using test sets two and three and validated on the final set of records.

Results

Of 107 systematic reviews which met our inclusion criteria, 1948 unique included studies were available from medline and 1980 from Embase. Generic adverse drug effects searches in medline and Embase achieved 90% and 89% relative recall, respectively. When specific adverse effects terms were added recall was improved.

Conclusion

We have derived and validated search filters that retrieve around 90% of records with adverse drug effects data in medline and Embase. The addition of specific adverse effects terms is required to achieve higher recall.  相似文献   

11.

Background

Degenerative cervical myelopathy (DCM) is a recently proposed umbrella term for symptomatic cervical spinal cord compression secondary to degeneration of the spine. Currently literature searching for DCM is challenged by the inconsistent uptake of the term ‘DCM’ with many overlapping keywords and numerous synonyms.

Objectives

Here, we adapt our previous Ovid medline search filter for the Ovid embase database, to support comprehensive literature searching. Both embase and medline are recommended as a minimum for systematic reviews.

Methods

References contained within embase identified in our prior study formed a ‘development gold standard’ reference database (N = 220). The search filter was adapted for embase and checked against the reference database. The filter was then validated against the ‘validation gold standard’.

Results

A direct translation was not possible, as medline indexing for DCM and the keywords search field were not available in embase . We also used the ‘focus’ function to improve precision. The resulting search filter has 100% sensitivity in testing.

Discussion and Conclusion

We have developed a validated search filter capable of retrieving DCM references in embase with high sensitivity. In the absence of consistent terminology and indexing, this will support more efficient and robust evidence synthesis in the field.  相似文献   

12.
OBJECTIVES: To detect term(s) in the Cochrane Highly Sensitive Search Strategy (HSSS) that retain high sensitivity but improve precision in retrieving reports of trials in the PubMed version of medline. METHODS: Individual terms from the PubMed version of the HSSS were added, term by term, to an African HIV/AIDS strategy to identify reports of trials in medline using PubMed. The titles and abstracts of the records retrieved were read by two handsearchers and checked by a clinical epidemiologist. The sensitivity and precision of each term in the three phases of the HSSS were calculated. RESULTS: Of 7,719 records retrieved, 285 were identified as reports of trials [204 randomized (RCTs); 81 possibly randomized or quasi-randomized (CCTs)]. Phase III had the highest sensitivity (92%). Overall, precision was very low (3.7%). One term, 'random*[tw]', retrieved all RCTs found by our search and improved precision to 29%. The least sensitive terms, yielding no records, were '(doubl* AND mask*)[tw]' and terms containing 'trebl*' or 'tripl*', except for '(tripl* AND blind*)[tw]'. The highest precision per term was for 'Double-blind Method [MeSH]' (76%). CONCLUSIONS: To retrieve all RCTs and CCTs found by our search, seven terms are needed but precision remains low (4.3%). Developments in the methods of search strategy design may help to improve precision while retaining high levels of sensitivity by identifying term(s) which occur frequently in relevant records and are the most efficient at discriminating between different study designs.  相似文献   

13.
The Internet has created new opportunities for librarians to present literature search results to clinicians. In order to take full advantage of these opportunities, libraries need to create locally maintained bibliographic databases. A simple method of creating a local bibliographic database and publishing it on the Web is described. The method uses off-the-shelf software and requires minimal programming. A hedge search strategy for outcome studies of clinical process interventions is created, and Ovid is used to search MEDLINE. The search results are saved and imported into EndNote libraries. The citations are modified, exported to a Microsoft Access database, and published on the Web. Clinicians can use a Web browser to search the database. The bibliographic database contains 13,803 MEDLINE citations of outcome studies. Most searches take between four and ten seconds and retrieve between ten and 100 citations. The entire cost of the software is under $900. Locally maintained bibliographic databases can be created easily and inexpensively. They significantly extend the evidence-based health care services that libraries can offer to clinicians.  相似文献   

14.
Background: Romania is a low‐income country of 22 million people and, currently, information regarding mental health research is limited. Romania is one of the last countries in eastern Europe not to have its own bibliographic biomedical database. Aim: To assess the content and quality of Romanian psychiatric research activity over time. Method: embase (1980 to April 2008), medline (1950 to April 2008) and Psyc INFO (1806 to April 2008) were systematically searched for psychiatric articles originating from Romania. The sample from Psyc INFO was described. Results: Psyc INFO was by far the best source of Romanian mental health literature with a considerable increase in the publication activity since 2000 (Psyc INFO identified 3236 hits, medline 549, embase 139). Most papers are in English, but a sizeable minority are in Romanian (30%), French (4%) or Hungarian (4%). The main topics of interest are cognitive processes, creativity, schizophrenia and cognitive development and stress and are, according to Psyc INFO’s indexing, ‘empirical studies’. Seventeen randomised trials were identified with all studies after 2000 being sponsored by industry. Conclusions: Surprisingly, and not in keeping with other studies of the literature of neighbouring countries, Psyc INFO is the major source of psychiatric bibliographic records of this region. There are signs of a resurgence of research activity in Romania and as the number of local mental health workers increases we can expect more output. Industry is now funding evaluative studies in Romania. As everywhere, but perhaps more acutely in situations of severely limited research support, there is a difficult balance to be struck between benefiting support and losing independence.  相似文献   

15.
Background: The researchers involved in this study work at Exeter Health library and at the Complementary Medicine Unit, Peninsula School of Medicine and Dentistry (PCMD). Within this collaborative environment it is possible to access the electronic resources of three institutions. This includes access to amed and other databases using different interfaces. Objectives: The aim of this study was to investigate whether searching different interfaces to the amed allied health and complementary medicine database produced the same results when using identical search terms. Methods: The following Internet‐based amed interfaces were searched: DIALOG DataStar; EBSCOhost and OVID SP_UI01.00.02. Search results from all three databases were saved in an endnote database to facilitate analysis. A checklist was also compiled comparing interface features. Results: In our initial search, DIALOG returned 29 hits, OVID 14 and Ebsco 8. If we assume that DIALOG returned 100% of potential hits, OVID initially returned only 48% of hits and EBSCOhost only 28%. In our search, a researcher using the Ebsco interface to carry out a simple search on amed would miss over 70% of possible search hits. Subsequent EBSCOhost searches on different subjects failed to find between 21 and 86% of the hits retrieved using the same keywords via DIALOG DataStar. In two cases, the simple EBSCOhost search failed to find any of the results found via DIALOG DataStar. Conclusions: Depending on the interface, the number of hits retrieved from the same database with the same simple search can vary dramatically. Some simple searches fail to retrieve a substantial percentage of citations. This may result in an uninformed literature review, research funding application or treatment intervention. In addition to ensuring that keywords, spelling and medical subject headings (MeSH) accurately reflect the nature of the search, database users should include wildcards and truncation and adapt their search strategy substantially to retrieve the maximum number of appropriate citations possible. Librarians should be aware of these differences when making purchasing decisions, carrying out literature searches and planning user education.  相似文献   

16.
Background: Access to a comprehensive public health index or database has been identified as problematic for health professionals. Public health literature contains many varied sources including reports, journal articles, and grey literature. Traditional biomedical databases such as medline often do not meet the needs of public health workers and researchers. Aim/Methods: The aim of the study was to examine the unique content of the global health database, by comparing it to the medline database. Pre‐determined terms were used as baseline comparators where controlled vocabulary definitions in each database were sufficiently matched. Retrieved results were stored and compared using EndNote libraries. Results: Results obtained from the terms used in the comparison study protocol suggest that the global health database holds a high proportion of unique records in comparison to medline . The largest overlap of duplicates from the global health database perspective came from the coccidiomycosis results set which contained 70.5% of references retrieved from both databases. Analyzing the results from a medline perspective, the subject with the largest overlap was dengue, with a 43% overlap. Conclusion: The results of this study show that the global health database is complimentary to medline in the subject areas of public health and global health.  相似文献   

17.

Objective

The purpose of this study was to investigate the relative effectiveness of three web-scale discovery (WSD) tools in answering health sciences search queries.

Methods

Simple keyword searches, based on topics from six health sciences disciplines, were run at multiple real-world implementations of EBSCO Discovery Service (EDS), Ex Libris''s Primo, and ProQuest''s Summon. Each WSD tool was evaluated in its ability to retrieve relevant results and in its coverage of MEDLINE content.

Results

All WSD tools returned between 50%–60% relevant results. Primo returned a higher number of duplicate results than the other 2 WSD products. Summon results were more relevant when search terms were automatically mapped to controlled vocabulary. EDS indexed the largest number of MEDLINE citations, followed closely by Summon. Additionally, keyword searches in all 3 WSD tools retrieved relevant material that was not found with precision (Medical Subject Headings) searches in MEDLINE.

Conclusions

None of the 3 WSD products studied was overwhelmingly more effective in returning relevant results. While difficult to place the figure of 50%–60% relevance in context, it implies a strong likelihood that the average user would be able to find satisfactory sources on the first page of search results using a rudimentary keyword search. The discovery of additional relevant material beyond that retrieved from MEDLINE indicates WSD tools'' value as a supplement to traditional resources for health sciences researchers.  相似文献   

18.
交互式跨语言信息检索是信息检索的一个重要分支。在分析交互式跨语言信息检索过程、评价指标、用户行为进展等理论研究基础上,设计一个让用户参与跨语言信息检索全过程的用户检索实验。实验结果表明:用户检索词主要来自检索主题的标题;用户判断文档相关性的准确率较高;目标语言文档全文、译文摘要、译文全文都是用户认可的判断依据;翻译优化方法以及翻译优化与查询扩展的结合方法在用户交互环境下非常有效;用户对于反馈后的翻译仍然愿意做进一步选择;用户对于与跨语言信息检索系统进行交互是有需求并认可的。用户行为分析有助于指导交互式跨语言信息检索系统的设计与实践。  相似文献   

19.
Background: Research on identifying trials using geographic filters is limited. Objectives:  To test the sensitivity and precision of a filter to identify African randomised controlled trials (RCTs). Methods: We searched medline and embase for RCTs published in 2004 using a Cochrane filter for RCTs. The search was limited to HIV/AIDS but irrespective of location. Two investigators independently identified African RCTs from the retrieved records forming a reference set. We then repeated the search using an African geographic filter comprising country and regional terms forming the filter set. We compared the sensitivity and precision of the sets. Results: The medline reference set comprised 1799 records with 23 African RCTs; for embase , the reference set comprised 763 records with 37 African RCTs. The medline filter set comprised 180 records with 17 African RCTs; the embase filter set comprised 98 records with 27 African RCTs. Sensitivity of the filter was 74% (medline ) and 73% (embase ). Addition of the filter improved precision from 1.3% to 9.4% (medline ) and from 5% to 28% (embase ). Conclusion: The African filter improved precision with some loss in sensitivity. Incomplete reporting of trial location in electronic bibliographic records restricts efficiency of geographic filters. Prospective trial registration should alleviate this.  相似文献   

20.
Relevance feedback methods generally suffer from topic drift caused by word ambiguities and synonymous uses of words. Topic drift is an important issue in patent information retrieval as people tend to use different expressions describing similar concepts causing low precision and recall at the same time. Furthermore, failing to retrieve relevant patents to an application during the examination process may cause legal problems caused by granting an existing invention. A possible cause of topic drift is utilizing a relevance feedback-based search method. As a way to alleviate the inherent problem, we propose a novel query phrase expansion approach utilizing semantic annotations in Wikipedia pages, trying to enrich queries with phrases disambiguating the original query words. The idea was implemented for patent search where patents are classified into a hierarchy of categories, and the analyses of the experimental results showed not only the positive roles of phrases and words in retrieving additional relevant documents through query expansion but also their contributions to alleviating the query drift problem. More specifically, our query expansion method was compared against relevance-based language model, a state-of-the-art query expansion method, to show its superiority in terms of MAP on all levels of the classification hierarchy.  相似文献   

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