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1.

Background

Systematic reviews risk producing biased conclusions if a comprehensive search to identify eligible studies is not undertaken, but little evidence exists to guide prioritisation of databases to search when resources are limited.

Objectives

A systematic review examining interventions for managing frozen shoulder (adhesive capsulitis) was used to investigate the performance of bibliographic databases in identifying the included studies, the smallest combination of databases required to retrieve all included studies, and the performance of the searches themselves.

Methods

We calculated the yield of included studies from each of 15 databases, and the recall and precision of each search strategy. We investigated differences between the presence of a record in a database and its retrieval.

Results

Thirty of 31 studies were present in at least one database. Yields of individual databases ranged from 0% to 90% (median 23%). Two combinations of databases identified all 30 studies: Cochrane Central Register of Controlled Trials (CENTRAL) and Science Citation Index (SCI); or CENTRAL, MEDLINE and PreMEDLINE.

Conclusions

In a systematic review of a range of interventions used to manage frozen shoulder, at least two databases and reference checking were required to retrieve all included studies, but searching for future reviews should not be restricted.  相似文献   

2.

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   

3.
Objective:The aim of this project was to validate search filters for systematic reviews, intervention studies, and observational studies translated from Ovid MEDLINE and Embase syntax and used for searches in PubMed and Embase.com during the development of evidence summaries supporting first aid guidelines. We aimed to achieve a balance among recall, specificity, precision, and number needed to read (NNR).Methods:Reference gold standards were constructed per study type derived from existing evidence summaries. Search filter performance was assessed through retrospective searches and measurement of relative recall, specificity, precision, and NNR when using the translated search filters. Where necessary, search filters were optimized. Adapted filters were validated in separate validation gold standards.Results:Search filters for systematic reviews and observational studies reached recall of ≥85% in both PubMed and Embase. Corresponding specificities for systematic review filters were ≥96% in both databases, with a precision of 9.7% (NNR 10) in PubMed and 5.4% (NNR 19) in Embase. For observational study filters, specificity, precision, and NNR were 68%, 2%, and 51 in PubMed and 47%, 0.8%, and 123 in Embase, respectively. These filters were considered sufficiently effective. Search filters for intervention studies reached a recall of 85% and 83% in PubMed and Embase, respectively. Optimization led to recall of ≥95% with specificity, precision, and NNR of 49%, 1.3%, and 79 in PubMed and 56%, 0.74%, and 136 in Embase, respectively.Conclusions:We report validated filters to search for systematic reviews, observational studies, and intervention studies in guideline projects in PubMed and Embase.com.  相似文献   

4.
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5.
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6.
Background: Literature for a systematic review on the student experience of e‐learning is located across a range of subject areas including health, education, social science, library and information science. Objectives: To assess the merits and shortcomings of using different search techniques in retrieval of evidence in the social science literature. Methods: A conventional subject search was undertaken as the principal method of identifying the literature for the review. Four supplementary search methods were used including citation searching, reference list checking, contact with experts and pearl growing. Results: The conventional subject search identified 30 of 41 included references; retrieved from 10 different databases. References were missed by this method and a further 11 references were identified via citation searching, reference list checking and contact with experts. Pearl growing was suspended as the nominated pearls were dispersed across numerous databases, with no single database indexing more than four pearls. Conclusions: Searching within the social sciences literature requires careful consideration. Conventional subject searching identified the majority of references, but additional search techniques were essential and located further high quality references.  相似文献   

7.
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   

8.
Background: Search filters have been developed in MEDLINE and EMBASE to help overcome the challenges of searching electronic databases for information on adverse effects. However, little evaluation of their effectiveness has been carried out. Objectives: To measure the sensitivity and precision of available adverse effects search filters in MEDLINE and EMBASE. Methods: A case study systematic review of fracture related adverse effects associated with the use of thiazolidinediones was used. Twelve MEDLINE search strategies and three EMBASE search strategies were tested. Results: Nineteen relevant references from MEDLINE and 24 from EMBASE were included in the review. Four search filters in MEDLINE achieved high sensitivity (95 or 100%) with an improved level of precision from searches without any adverse effects filter. High precision in MEDLINE could also be achieved (up to 53%) using search filters that rely on Medical Subject Headings. No search filter in EMBASE achieved high precision (all were under 5%) and the highest sensitivity in EMBASE was 83%. Conclusions: Adverse effects search filters appear to be effective in MEDLINE for achieving either high sensitivity or high precision. Search filters in EMBASE, however, do not appear as effective, particularly in improving precision.  相似文献   

9.
Cited author searches were conducted in Nursing Citation Index to determine its utility in locating clinical studies that apply the conceptual frameworks of Dorothea Orem, Callista Roy, Martha Rogers, Betty Neuman, and Dorothy Johnson. Fully 75 percent of the relevant papers would have been missed by a conventional subject/textword search in the MEDLINE or CINAHL databases. Had Nursing Citation Index not been available, only 22 percent of relevant papers could have been retrieved by cited author searches of Social Science Citation Index. In summary, Nursing Citation Index provides an important indexing link between nursing theory and nursing research.  相似文献   

10.

Background

Search filter development for adverse effects has tended to focus on retrieving studies of drug interventions. However, a different approach is required for surgical interventions.

Objective

To develop and validate search filters for medline and Embase for the adverse effects of surgical interventions.

Methods

Systematic reviews of surgical interventions where the primary focus was to evaluate adverse effect(s) were sought. The included studies within these reviews were divided randomly into a development set, evaluation set and validation set. Using word frequency analysis we constructed a sensitivity maximising search strategy and this was tested in the evaluation and validation set.

Results

Three hundred and fifty eight papers were included from 19 surgical intervention reviews. Three hundred and fifty two papers were available on medline and 348 were available on Embase. Generic adverse effects search strategies in medline and Embase could achieve approximately 90% relative recall. Recall could be further improved with the addition of specific adverse effects terms to the search strategies.

Conclusion

We have derived and validated a novel search filter that has reasonable performance for identifying adverse effects of surgical interventions in medline and Embase. However, we appreciate the limitations of our methods, and recommend further research on larger sample sizes and prospective systematic reviews.  相似文献   

11.
Background: Measures of the effectiveness of databases have traditionally focused on recall, precision, with some debate on how relevance can be assessed, and by whom. New measures of database performance are required when users are familiar with search engines, and expect full text availability. Objectives: This research ascertained which of four bibliographic databases (bni, cinahl, medline and embase ) could be considered most useful to nursing and midwifery students searching for information for an undergraduate dissertation. Methods: Searches on title were performed for dissertation topics supplied by nursing students (n = 9), who made the relevance judgements. Measures of recall and precision were combined with additional factors to provide measures of effectiveness, while efficiency combined measures of novelty and originality and accessibility combined measures for availability and retrievability, based on obtainability. Results: There were significant differences among the databases in precision, originality and availability, but other differences were not significant (Friedman test). Odds ratio tests indicated that bni , followed by cinahl were the most effective, cinahl the most efficient, and bni the most accessible. Conclusions: The methodology could help library services in purchase decisions as the measure for accessibility, and odds ratio testing helped to differentiate database performance.  相似文献   

12.
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   

13.
Background: The Australian National Stroke Foundation appointed a search specialist to find the best available evidence for the second edition of its Clinical Guidelines for Acute Stroke Management. Objective: To identify the relative effectiveness of differing evidence sources for the guideline update. Methods: We searched and reviewed references from five valid evidence sources for clinical and economic questions: (i) electronic databases; (ii) reference lists of relevant systematic reviews, guidelines, and/or primary studies; (iii) table of contents of a number of key journals for the last 6 months; (iv) internet/grey literature; and (v) experts. Reference sources were recorded, quantified, and analysed. Results: In the clinical portion of the guidelines document, there was a greater use of previous knowledge and sources other than electronic databases for evidence, while there was a greater use of electronic databases for the economic section. Conclusions: The results confirmed that searchers need to be aware of the context and range of sources for evidence searches. For best available evidence, searchers cannot rely solely on electronic databases and need to encompass many different media and sources.  相似文献   

14.
Ten students in a freshman Elementary Composition course were observed as they searched bibliographic databases on a CD-ROM LAN. All were preparing term papers, and were asked to think aloud as they conducted their searches. A total of 329 relevance judgments were made as the students searched an average of 2.7 databases per session. Basic familiarity with computers and a tendency to get out of unproductive searches helped in avoiding problems with the variety of databases and search interfaces. All students found records they chose to print, with relevance judgments often made from information in the controlled vocabulary, title, or abstract. The browse interface was used most often, and its similarity to InfoTrac was helpful. Some students were able to use keyword access effectively, though Wilsondisc's multiterm search required adjustments and adaptation of strategies. SilverPlatter's record display and print functions caused confusion for searchers unfamiliar with this interface.  相似文献   

15.
Objective:This study retroactively investigated the search used in a 2019 review by Hayden et al., one of the first systematic reviews of prognostic factors that was published in the Cochrane Library. The review was designed to address recognized weaknesses in reviews of prognosis by using multiple supplementary search methods in addition to traditional electronic database searching.Methods:The authors used four approaches to comprehensively assess aspects of systematic review literature searching for prognostic factor studies: (1) comparison of search recall of broad versus focused electronic search strategies, (2) linking of search methods of origin for eligible studies, (3) analysis of impact of supplementary search methods on meta-analysis conclusions, and (4) analysis of prognosis filter performance.Results:The review''s focused electronic search strategy resulted in a 91% reduction in recall, compared to a broader version. Had the team relied on the focused search strategy without using supplementary search methods, they would have missed 23 of 58 eligible studies that were indexed in MEDLINE; additionally, the number of included studies in 2 of the review''s primary outcome meta-analyses would have changed. Using a broader strategy without supplementary searches would still have missed 5 studies. The prognosis filter used in the review demonstrated the highest sensitivity of any of the filters tested.Conclusions:Our study results support recommendations for supplementary search methods made by prominent systematic review methodologists. Leaving out any supplemental search methods would have resulted in missed studies, and these omissions would not have been prevented by using a broader search strategy or any of the other prognosis filters tested.

Open in a separate windowLeah Boulos  相似文献   

16.
The article reports on a systematic method of undertaking a literature search on the educational impact of being a young carer (16–24 years old). The search methodology applied and described in detail will be of value to academic librarians and to other education researchers who undertake systematic literature searches. Seven bibliographic databases and Google Scholar were searched between November 2015 and January 2016. Two and three concept search structures were compared, involving 28 search terms plus truncation variants. One hundred and eighty-one relevant articles were retrieved. Sensitivity, precision, and “unique articles retrieved” were used as metrics. Social Care Online and Google Scholar had the greatest sensitivity. As well as meticulous use of AND, OR, and bracket operators, the use of NEAR and NOT operators to increase precision were tested and are recommended as useful tools for conducting systematic searches.  相似文献   

17.
Summary

This study examines the search tactics used by Web users to start their searches and deal with search problems such as too many postings and no relevant postings. Four search topics were developed to allow for comparison of search tactics used in four types of searches. The tactics analyzed include search statements, number of search statements, starting points, and tactics to solve the two search problems mentioned above. Search statements were searched in Alta Vista to determine their success and their nature was analyzed. With regard to the tactics used to address search problems, t-tests and chi-square tests found no difference between searches for texts and searches for graphic information, and between known-item searches and subject searches. Some of Web users' search tactics were similar to those for online searching or online catalog searches, but several tactics were unique to Web searching.  相似文献   

18.
从分析当前书目数据库的特征入手，依次对题名、主题、分类号等项目的数据质量和标引特征进行分析，得出在现有的书目数据质量情况下，几乎没有一条提高查全率和查准率的综合性检索途径的结论。针对现状，指出提高书目数据库检索效果和检索精度的必要性，并对如何提高检索质量的问题进行研究，研究内容包括检索语言兼容性和检索方法的扩展性，并为提高书目数据检索的综合质量、增加书目检索系统的开放性探索提供方案。  相似文献   

19.
Objective:Locating systematic reviews is essential for clinicians and researchers when creating or updating reviews and for decision-making in health care. This study aimed to develop a search filter for retrieving systematic reviews that improves upon the performance of the PubMed systematic review search filter.Methods:Search terms were identified from abstracts of reviews published in Cochrane Database of Systematic Reviews and the titles of articles indexed as systematic reviews in PubMed. Both the precision of the candidate terms and the number of systematic reviews retrieved from PubMed were evaluated after excluding the subset of articles retrieved by the PubMed systematic review filter. Terms that achieved a precision greater than 70% and relevant publication types indexed with MeSH terms were included in the filter search strategy.Results:The search strategy used in our filter added specific terms not included in PubMed''s systematic review filter and achieved a 61.3% increase in the number of retrieved articles that are potential systematic reviews. Moreover, it achieved an average precision that is likely greater than 80%.Conclusions:The developed search filter will enable users to identify more systematic reviews from PubMed than the PubMed systematic review filter with high precision.  相似文献   

20.
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   

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