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1.
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   

2.
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   

3.
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   

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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   

6.
Background: Considerable barriers still prevent paediatricians from successfully using information retrieval technology. Objectives: To verify whether the assistance of biomedical librarians significantly improves the outcomes of searches performed by paediatricians in biomedical databases using real‐life clinical scenarios. Methods: In a controlled trial at a paediatric teaching hospital, nine residents and interns were randomly allocated to an assisted search group and nine to a non‐assisted (control) group. Each participant searched Pub Med and other online sources, performing pre‐determined tasks including the formulation of a clinical question, retrieval and selection of bibliographic records. In the assisted group, participants were supported by a librarian with ≥5 years of experience. The primary outcome was the success of search sessions, scored against a specific assessment tool. Results: The median score of the assisted group was 73.6 points interquartile range (IQR = 13.4) vs. 50.4 (IQR = 17.1) of the control group. The difference between median values in the results was 23.2 points (95% CI 4.8–33.2), in favour of the assisted group (P‐value, Mann–Whitney U test: 0.013). Conclusions: The study has found quantitative evidence of a significant difference in search performance between paediatric residents or interns assisted by a librarian and those searching the literature alone.  相似文献   

7.
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   

8.
BACKGROUND: Cochrane-style systematic reviews increasingly require the participation of librarians. Guidelines on the appropriate search strategy to use for systematic reviews have been proposed. However, research evidence supporting these recommendations is limited. OBJECTIVE: This study investigates the effectiveness of various systematic search methods used to uncover randomized controlled trials (RCTs) for systematic reviews. Effectiveness is defined as the proportion of relevant material uncovered for the systematic review using extended systematic review search methods. The following extended systematic search methods are evaluated: searching subject-specific or specialized databases (including trial registries), hand searching, scanning reference lists, and communicating personally. METHODS: Two systematic review projects were prospectively monitored regarding the method used to identify items as well as the type of items retrieved. The proportion of RCTs identified by each systematic search method was calculated. RESULTS: The extended systematic search methods uncovered 29.2% of all items retrieved for the systematic reviews. The search of specialized databases was the most effective method, followed by scanning of reference lists, communicating personally, and hand searching. Although the number of items identified through hand searching was small, these unique items would otherwise have been missed. CONCLUSIONS: Extended systematic search methods are effective tools for uncovering material for the systematic review. The quality of the items uncovered has yet to be assessed and will be key in evaluating the value of the systematic search methods.  相似文献   

9.
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   

10.
Background: Complementary and alternative medicine (CAM) has succeeded to implement itself in the academic context of universities. In order to get information on CAM, clinicians, researchers and healthcare professionals as well as the lay public are increasingly turning to online portals and databases, which disseminate relevant resources. One specific type of online information retrieval systems, namely the database, is being reviewed in this article. Question: This overview aims at systematically retrieving and describing all databases covering the field of CAM. One of the requirements for inclusion was that the database would also have to be published in a medical journal. Data sources: The databases amed , CAMbase , embase , and medline /Pub Med were searched between December 2008 and December 2009 for publications relevant to CAM databases. The authors’ specialist library was also searched for grey literature to be included. Study selection: All included databases were then visited online and information on the context, structure and volume of the database was extracted. Main results: Forty‐five databases were included in this overview. Databases covered herbal therapies (n = 11), traditional Chinese medicine (n = 9) and some dealt with a vast number of CAM modalities (n = 9), amongst others. The amount of time the databases had been in existence ranged from 4 to 53 years. Countries of origin included the USA (n = 14), UK (n = 7) and Germany (n = 6), amongst others. The main language in 42 of 45 databases was English. Conclusions: Although this overview is quite comprehensive with respect to the field of CAM, certain CAM practices such as chiropractic, massage, reflexology, meditation or yoga may not have been covered adequately. A more detailed assessment of the quality of the included databases might give additional insights into the listed resources. The creation of a personalised meta‐search engine is suggested, towards which this overview could be seen as a first step.  相似文献   

11.
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   

12.
OBJECTIVE: To describe the development of the Cochrane Behavioral Medicine Field database of interventions and its contribution to the knowledge base of this field. METHODS: A list of behavioural medicine interventions was solicited from content experts. The resulting list of index terms was used to generate a comprehensive search strategy to retrieve relevant records, and a thesaurus of terms with which to index them. The records are included in a register. A subset of records have been coded for study design, health condition, intervention, study participants, setting and provider and made available in a public online database. RESULTS: The Cochrane Behavioral Medicine Field database consists of over 3500 records of systematic reviews, meta-analyses and randomized controlled trials for public educational use. CONCLUSIONS: The register provides a comprehensive listing of studies relating to behavioural medicine interventions. The public online database enables easy access to the evidence base and provides enhanced details of the studies included on it. These databases are a valuable resource for the behavioural medicine community. Other fields are encouraged to duplicate these methods in the design of content-specific databases.  相似文献   

13.
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   

14.
Objective:In regard to locating clinical trials for a systematic review, limited information is available about how librarians locate clinical trials in biomedical databases, including (1) how much information researchers provide librarians to assist with the development of a comprehensive search strategy, (2) which tools librarians turn to for information about study design methodology, and (3) librarians'' confidence levels in their knowledge of study design methodology. A survey was developed to explore these aspects of how a medical librarian locates clinical trials when facilitating systematic reviews for researchers.Methods:In this cross-sectional study, a 21-question survey was sent to medical librarians via several email listservs during April 2020. Respondents were limited to librarians who make the decisions on search terms for systematic reviews.Results:Responses (n=120) indicated that librarians were often asked to search for various types of clinical trials. However, there was not a consistent method for creating search strategies that locate diverse types of clinical trials. Multiple methods were used for search strategy development, with hedges being the most popular method. In general, these librarians considered themselves to be confident in locating trials. Different resources were used to inform study types, including textbooks, articles, library guides and websites.Discussion:Medical librarians indicated that while they felt confident in their searching skills, they did not have a definitive source of information about the various types of clinical trials, and their responses demonstrated a clear need and desire for more information on study design methodology.  相似文献   

15.
我国四大引文数据库比较分析   总被引:22,自引:0,他引:22  
曹志梅  王凯 《情报学报》2002,21(4):481-485
本文针对目前最常用的四个引文数据库 :《中国科学引文数据库》、《中国科技论文与引文数据库》、《中文社会科学引文索引》、《中国学术期刊全文数据库》 ,从数据库收录数据、检索途径、检索功能等方面进行了比较分析 ,并针对使用中存在的一些问题 ,对数据库的改进提出了建议。  相似文献   

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Electronic resources librarians mediate access to a variety of resources and content ranging from electronic journals and databases provided by publishers and vendors to locally produced web pages, documentation, and instructional videos. Providing accessible resources is essential to ensuring equal access and opportunity for students, faculty, and staff in higher education. This article explains accessibility and provides strategies for creating an accessibility initiative at your college or university.  相似文献   

18.
Abstract

There are a few studies in library literature that explore accessibility issues from the perspective of students who use assistive technologies for accessibility. As we shared in part one of this two-part series in our column, librarians have extensively explored through usability studies with WAVE and other audit tools how accessible library websites and databases are when using assistive technologies like JAWS. In this column, we asked our blind student worker to journal his experiences navigating our library’s databases. We found this student navigated the databases better than we anticipated. While his experiences regarding the accessibility of the libraries’ electronic services varied, common issues he experienced included navigational issues from menus with expanding capabilities, documents that were not scanned with OCR, and images without alternative text.  相似文献   

19.
End-user search software is designed to simplify online searching for the casual searcher. User-friendly features provide relatively easy online access to remote databases without the need for expert search systems. At issue is whether the simplified features of such software compromise what is potentially retrievable, and if so, whether the missing information is critical to the end user. A study was designed to address this question, particularly as applied to clinicians using a user-friendly search software package such as Grateful Med. Clinician participants compared their Grateful Med search results with a full Elhill search (as performed by an intermediary) and indicated whether references unique to either search were or were not critical to their information needs.  相似文献   

20.
A double-blind randomised controlled trial was conducted on a group of Hong Kong hospital clinicians. The objective was to test if a three-hour educational workshop (with supervised hands-on practice) is more effective (than no training) to improve clinical question formulation, information-seeking skills, knowledge, attitudes, and search outcomes. The design was a post-test-only control group; recruitment by stratified randomization (by profession), blocked at 800. End-user training was more effective than no training in improving clinical question formulation, in raising awareness, knowledge, confidence and use of databases, but had made no impact on preference for secondary databases. It changed the attitude of clinicians to become more positive towards the use of electronic information services (EIS). Participants had higher search performance and outcomes (satisfaction with information obtained (NNT = 3), EIS satisfaction (NNT = 3) and success in problem solving (NNT = 4)). The workshop improved knowledge and skills in evidence-based searching, but this effect gradually eroded with time. Search logs confirmed that follow-up is required if effects are to be sustained. Longer effects on search behaviours appear to be positive. A randomised controlled trial is valuable in identifying cause-and-effect relations and to quantify the magnitude of the effects for management decision-making.  相似文献   

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