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1.
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   

2.
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   

3.
Introduction: Locating reports of trials from journals not indexed in the major databases presents difficulties to systematic reviewers, and may be a factor in improving the reliability of the reviews. Objectives: To identify and make available reports of controlled trials from the Australasian Medical Index (AMI). To measure the quality of indexing of trials in AMI. Methods: Using a highly sensitive search strategy consisting of methodology indexing and free‐text terms, records from AMI were read for reports of controlled trials. Trials meeting the criteria were submitted for inclusion in The Cochrane Controlled Trials Register (CCTR) and assessed for the quality of their indexing. Results: 3621 records were downloaded, of which 512 were identified as reports of controlled trials (317 RCTs; 195 CCTs) and submitted to CCTR. The precision of methodology indexing terms was 60%, but sensitivity just 18%. The quality of indexing of trials was generally poor with only 50 tagged with the RCT/CCT publication type term. 453 reports (88%) were not previously available in CCTR. Conclusions: The large proportion of trials found to be unique to the AMI database increases the pool of studies available to systematic reviewers, and helps ensure CCTR remains the most comprehensive source of trials.  相似文献   

4.
Background: Thailand is a poor but highly literate country in South‐East Asia with over 60 million people. A lot of biomedical research is undertaken but dissemination is limited. Objectives: To identify relevant Thai bibliographic databases and investigate accessibility, functionality and content, particularly in relation to randomised controlled trials (RCTs) and clinical controlled trials (CCTs). Methods: A systematic search for institutions productive of research and the databases in their libraries. Search each accessible database in both Thai and English, recording the functionality and content. Assess accessibility of the retrieved RCTs or CCTs by comparing to Pub Med holdings. Results: We found 32 different databases (29 accessible in UK) of various sizes, coverage and functionality but many with unique records of RCTs and CCTs (total, n = 781). Two hundred and nine of 781 trials were accessible on Pub Med (27%). However, 641 of the 781 trial records contain text in both English and Thai (82%) and 112 records were solely English (14%). Conclusions: Those undertaking comprehensive searches for RCTs/CCTs should, in addition to a Pub Med , search the Thai Medical Index and Thai Index Medicus databases, and the Khon Kaen University Library Catalogue.  相似文献   

5.
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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.
Background/objectives: Methodological decisions made during the research process can influence generalizability of findings to real world practice. The aims of this study were to explore the impact of decisions made in the development of a palliative care search filter and to consider the implications for implementation. Methods: Three elements of the original study methodology were explored: (i) choice of OVID medline field delimiters; (ii) use of the general medical literature to evaluate the filter's performance; and (iii) use of the OVID interface. Sensitivity, specificity, accuracy and precision rates of variant search strategies were compared to consider each issue. Results: The delimiter .af. outperformed the alternatives of .tw. or .mp. in OVID medline , improving sensitivity from 45.4 to 46.2%. Applying the filter in the specialist palliative literature resulted in 87.5% (692/791) of articles being retrieved using either .tw. or .mp., increasing to 100% (791/791) with the .af. delimiter. Finally, a PubMed version of the filter was successfully validated. Conclusions: Reviewing three methodological decisions that preserved validity in an original study led to the improved utility of a search filter in practice. Generating high‐quality evidence is only part of evidence‐based practice: consideration of generalizability issues can inform further research and effective evidence implementation.  相似文献   

8.
OBJECTIVES: To assess the performance of published search filters in finding diagnostic test accuracy studies. METHODS: Diagnostic test accuracy search filters were identified by searching medline, our own files and by requesting unpublished filters from colleagues. We applied the filters to a case study review of diagnostic test accuracy studies for urinary tract infections (UTI) in young children. The included studies with records in medline formed the gold standard. The performance of the filters in finding those gold standard records was assessed. RESULTS: We identified twenty-three diagnostic test accuracy search filters for use with medline. The case study systematic review of UTI included 179 studies of diagnostic test accuracy, of which 160 were available in medline. The filters showed a wide range of sensitivities (range: 20.6% to 86.9%) and precision (range: 1% to 9.4%). CONCLUSIONS: Our results broadly support those reported in two other studies. The search filters tested do not offer an adequate trade-off between sensitivity and precision to be used to identify studies for systematic reviews. However, there are methods available to explore whether search filters are viable based on an objective statistical analysis of the text and indexing used in records.  相似文献   

9.
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   

10.
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   

11.
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   

12.

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   

13.

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   

14.
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   

15.
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   

16.
Background and objective: With the advent of an interprofessional approach to delivering health care in today's health care systems, should health care professionals be educated together? Supported by policy‐making circles worldwide, interprofessional education is accumulating a research literature at an exponential rate. Using one‐word search terms in the medline query box for scoping this body of literature, we obtained an unmanageable number of articles (342 338 in all fields). The objective of our study was to outline an efficient specific query. Methods: We created 1072 phrasal search terms consisting of a prefix, an adjective and a noun. Of those, 66 were prolific for the whole indexed period (1950–2006). Results: Only 2510 citations have the search term in all medline fields; of those 2049 were in title/abstract and 652 in title alone. From the 1950s, the citations were published at a slow rate, but the rate then exploded during the decade 1995 to 2006. The combination of prefixes ‘inter’ and ‘multi’ with the adjectives ‘professional’, ‘disciplinary’ and ‘shared’, and the nouns ‘education’, ‘learning’ and ‘training’ may retrieve almost all the relevant citations, while the terms ‘collaborative’ and ‘common’ may retrieve mainly irrelevant ones. The adjective ‘cohesive’ and nouns ‘practice’ and ‘role’ should be also considered. Conclusion: Phrasal search terms highly increased the relevance of medline ‐retrieved citations.  相似文献   

17.
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18.
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   

19.
Our objective was to perform a pilot study to estimate the proportion of published errata linked to randomized controlled trials (RCTs) that are worthwhile obtaining when doing a systematic review. medline was searched for records that had both 'randomized-controlled-trial' in the publication type field and 'erratum' in the comments field. One hundred records from four general medical journals were examined independently from two different perspectives. From the information specialist's perspective, 74% of the errata were considered worthwhile obtaining; these were mainly errors in tables or figures. Another 9% described less serious errors, but were worth obtaining if easily available. The other 17% were minor errors. From the perspective of the experienced reviewer/public health consultant, 5% of errata were classified as likely to affect a meta-analysis, and 10% as having significant errors that would affect the interpretation of the RCT, but no effect on a meta-analysis; 85% were not considered important enough to affect either. About 5% of errata to RCTs appeared to matter in terms of changing the final conclusions of a systematic review. However, the majority of errata were considered to be worthwhile obtaining, on the basis that having full and accurate data can reduce confusion and save reviewers time.  相似文献   

20.
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   

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