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![Randomized trials in Embase
Update 2011 – 2012 data
Year 2011 2012 All years
Language Embase PubMed Embase PubMed Embase PubMed
German 95 56 28 19 9152 6267
French 41 22 26 12 4525 2780
Italian 19 11 7 5 1973 1341
Turkish 58 8 36 - 756 84
Chinese 550 364 167 86 7381 5057
Example searches:
Embase: ‘randomized controlled trial’/de AND french:la
PubMed: "randomized controlled trial"[Publication Type] AND french[language]
Search date: 22 October 2012](https://image.slidesharecdn.com/embasewebinarebm-24oct2012-121026173310-phpapp02/75/Embase-Supporting-Evidence-Based-Medicine-Webinar-24-Oct-2012-22-2048.jpg)
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(systematic review [ti] OR meta-analysis [pt] OR meta-analysis [ti] OR systematic literature review [ti] OR (systematic
review [tiab] AND review [pt]) OR consensus development conference [pt] OR practice guideline [pt] OR cochrane
database syst rev [ta] OR acp journal club [ta] OR health technol assess [ta] OR evid rep technol assess summ [ta]) OR
((evidence based[ti] OR evidence-based medicine [mh] OR best practice* [ti] OR evidence synthesis [tiab]) AND (review
[pt] OR diseases category[mh] OR behavior and behavior mechanisms [mh] OR therapeutics [mh] OR evaluation
studies[pt] OR validation studies[pt] OR guideline [pt])) OR ((systematic [tw] OR systematically [tw] OR critical [tiab] OR
(study selection [tw]) OR (predetermined [tw] OR inclusion [tw] AND criteri* [tw]) OR exclusion criteri* [tw] OR main
outcome measures [tw] OR standard of care [tw] OR standards of care [tw]) AND (survey [tiab] OR surveys [tiab] OR
overview* [tw] OR review [tiab] OR reviews [tiab] OR search* [tw] OR handsearch [tw] OR analysis [tiab] OR critique
[tiab] OR appraisal [tw] OR (reduction [tw]AND (risk [mh] OR risk [tw]) AND (death OR recurrence))) AND (literature [tiab]
OR articles [tiab] OR publications [tiab] OR publication [tiab] OR bibliography [tiab] OR bibliographies [tiab] OR published
[tiab] OR unpublished [tw] OR citation [tw] OR citations [tw] OR database [tiab] OR internet [tiab] OR textbooks [tiab] OR
references [tw] OR scales [tw] OR papers [tw] OR datasets [tw] OR trials [tiab] OR meta-analy* [tw] OR (clinical [tiab] AND
studies [tiab]) OR treatment outcome [mh] OR treatment outcome [tw])) NOT (letter [pt] OR newspaper article [pt] OR
comment [pt])](https://image.slidesharecdn.com/embasewebinarebm-24oct2012-121026173310-phpapp02/75/Embase-Supporting-Evidence-Based-Medicine-Webinar-24-Oct-2012-27-2048.jpg)
![EBM: other approaches
Comparative Effectiveness Research (CER)
• Emtree term: comparative effectiveness
Added in 2010; approx. 2000 results/year from 2011
Cochrane Database of Systematic Reviews
• Advanced limit: [cochrane review]/lim
Over 11,000 reviews included in Embase since 2000](https://image.slidesharecdn.com/embasewebinarebm-24oct2012-121026173310-phpapp02/75/Embase-Supporting-Evidence-Based-Medicine-Webinar-24-Oct-2012-42-2048.jpg)
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Similar to Embase - Supporting Evidence Based Medicine - Webinar 24 Oct 2012
Embase - Supporting Evidence Based Medicine - Webinar 24 Oct 2012
- 1. Welcome to ourEmbase webinar! Embase - supporting Evidence Based Medicine Your host: Ann-Marie Roche Your presenter: Ian Crowlesmith
- 2.
- 3. Agenda • Medicine withoutevidence • EBM: what it is and what it isn’t • Using EBM in practice: PICO (with case study) • EBM in Embase - working with Cochrane - unique content in Embase (RCTs) - check tags and publication types • EBM: finding clinical evidence (with case studies) • Other approaches - practice guidelines - comparative effectiveness - systematic reviews
- 4. Medicine without evidence Johns Hopkins’ Tragedy: Could Librarians Have Prevented a Death? Source: http://newsbreaks.infotoday.com/nbreader.asp?ArticleID=17534 4
- 7. David L. Sackett,William M.C. Rosenberg, J.A. Muir Gray, R. Brian Haynes & W. Scott Richardson
- 8. David L. Sackettet al. The practice of evidence based medicine means integrating individual clinical expertise with the best available external evidence from systematic research. … By best available external clinical evidence we mean clinically relevant research, often from the basic sciences of medicine, but especially from patient centred clinical research into the accuracy and precision of diagnostic tests (including the clinical examination), the power of prognostic markers, and the efficacy and safety of therapeutic, rehabilitative, and preventive regimens.
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- 10. Levels of evidence OxfordCentre for Evidence-based Medicine - Levels of Evidence (Mar 2009) Ref: Nursetopia.net Parachutes reduce the risk of injury after gravitational challenge, but their effectiveness has not been proved with randomised controlled trials Source: Gordon Smith & Jill Pell, BMJ 2003;327:1459 Source: Robin Harbour & Juliet Miller (SIGN), BMJ 2001;323:334.1
- 11. Using EBM inpractice Formulate a clinical question Information specialist Use EBM to systematically look for relevant evidence Evaluate the evidence and integrate with clinical expertise Clinician Apply the results to the patient
- 12. Using EBM tosystematically look for relevant evidence P = Patient I = Intervention C = Comparison / Control O = Outcome
- 13. Case study Imagine yourselfas a medical intern or librarian who has been asked to advise a senior clinician about any risks that might be associated with the treatment of a patient under his care. http://www.youtube.com/watch?v=QzZbYMS1tQ4 (Source: see http://www.embase.com/info) Clinical question Are there any risks associated with the administration of antibiotics together with digoxin in a patient with congestive heart failure who has contracted pneumonia?
- 14. One possible solutionis in this paper ...
- 15. Using PICO inEmbase P = patient with congestive heart failure and pneumonia I = digoxin and antibiotics C = clinical trials or other levels of evidence? O = risks (e.g. interactions or side effects)
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- 18. EBM: the Embaseadvantage Extensive coverage: > 7,500 journals > 800,000 conference abstracts Indexed AiPs + In-process records Worldwide coverage (languages) Over 65 years: 25m records, 1947 – 2012 All MEDLINE records (Embase Classic abstracts) In depth indexing: > 30,000 drugs > 1,500 device terms (2012) EBM terminology: RCTs, CCTs, DTA studies Comparative effectiveness Systematic reviews
- 19. Collaboration with Cochrane 1993-present Year Embase enhancement 1993 Randomized controlled trial added to Emtree 1997 UK Cochrane Centre project to identify RCTs in Embase • 100,000 RCTs & CCTs from 1980 identified and updated in both Embase & the Cochrane database (CENTRAL) • Unique Embase coverage of non-English RCTs vs MEDLINE 2004 Systematic Review added to Emtree 2007 Controlled Clinical Trial added to Emtree 2011 Topic terms differentiated from study types for RCTs and 9 other terms in Emtree
- 20. Unique content inEmbase Carol Lefebvre MLA 2010 • ‘Embase is a rich source of reports of randomized trials that are either not included in MEDLINE or not indexed as trials in MEDLINE, especially reports in some languages other than English’. • ‘In addition to searching CENTRAL, people looking for reports of randomized trials should search Embase, as well as MEDLINE, for reports published in recent years that have not yet been considered for inclusion in CENTRAL’. Ref: Lefebvre et al. Emerging Themes in Epidemiology 2008 5:13
- 21. Randomized trials inEmbase Carol Lefebvre MLA 2010 PubMed 1) Embase ‘unique’ 1) Chinese 257 320 Dutch 3 13 Italian 11 15 Persian (Farsi) 0 6 Turkish 12 50 1) All data from 2005 Ref: Lefebvre et al. Emerging Themes in Epidemiology 2008 5:13
- 22. Randomized trials inEmbase Update 2011 – 2012 data Year 2011 2012 All years Language Embase PubMed Embase PubMed Embase PubMed German 95 56 28 19 9152 6267 French 41 22 26 12 4525 2780 Italian 19 11 7 5 1973 1341 Turkish 58 8 36 - 756 84 Chinese 550 364 167 86 7381 5057 Example searches: Embase: ‘randomized controlled trial’/de AND french:la PubMed: "randomized controlled trial"[Publication Type] AND french[language] Search date: 22 October 2012
- 23. Publication types andtopics • 10 EBM-related “topic terms” in Emtree • Introduced in 2011
- 24. Check tags forEBM in Embase Check tag Year Scope note Systematic 2004 Used for studies that systematically summarize all relevant evidence pertaining to a defined health question, and review including items identified as such by the author Meta 1987 Used for original reports evaluating medical interventions by the statistical analysis of a large collection of analysis results analysis from individual studies, for the purpose of integrating the findings; not limited to clinical trials Clinical trial 1974 Used for original reports of prospective clinical studies in which the (comparative) efficacy of one or more medical interventions in humans is evaluated; also used for prospective clinical veterinary trials in which the (comparative) efficacy of one or more medical interventions in animals is evaluated Human 1974 Used for all items where humans are a feature, including studies on human tissue, cells or cell components Sources: Emtree browser in Embase.com Embase Indexing Guide 2012 (via Embase.com/info)
- 25. EBM terms inEmbase / Emtree • via Advanced Limits in Advanced Search • via Emtree
- 26. Systematic reviews 20000 PubMed 18000 Embase 16000 14000 12000 10000 8000 6000 4000 2000 0 2004 2005 2006 2007 2008 2009 2010 2011 2012 Search strategies: PubMed: systematic[sb] Embase: [systematic review]/lim
- 27. Systematic reviews 20000 15000 Search strategy decoded: Embase 10000 systematic review/de 5000 (see check tag list for scope note) 0 Search strategy decoded: PubMed (systematic review [ti] OR meta-analysis [pt] OR meta-analysis [ti] OR systematic literature review [ti] OR (systematic review [tiab] AND review [pt]) OR consensus development conference [pt] OR practice guideline [pt] OR cochrane database syst rev [ta] OR acp journal club [ta] OR health technol assess [ta] OR evid rep technol assess summ [ta]) OR ((evidence based[ti] OR evidence-based medicine [mh] OR best practice* [ti] OR evidence synthesis [tiab]) AND (review [pt] OR diseases category[mh] OR behavior and behavior mechanisms [mh] OR therapeutics [mh] OR evaluation studies[pt] OR validation studies[pt] OR guideline [pt])) OR ((systematic [tw] OR systematically [tw] OR critical [tiab] OR (study selection [tw]) OR (predetermined [tw] OR inclusion [tw] AND criteri* [tw]) OR exclusion criteri* [tw] OR main outcome measures [tw] OR standard of care [tw] OR standards of care [tw]) AND (survey [tiab] OR surveys [tiab] OR overview* [tw] OR review [tiab] OR reviews [tiab] OR search* [tw] OR handsearch [tw] OR analysis [tiab] OR critique [tiab] OR appraisal [tw] OR (reduction [tw]AND (risk [mh] OR risk [tw]) AND (death OR recurrence))) AND (literature [tiab] OR articles [tiab] OR publications [tiab] OR publication [tiab] OR bibliography [tiab] OR bibliographies [tiab] OR published [tiab] OR unpublished [tw] OR citation [tw] OR citations [tw] OR database [tiab] OR internet [tiab] OR textbooks [tiab] OR references [tw] OR scales [tw] OR papers [tw] OR datasets [tw] OR trials [tiab] OR meta-analy* [tw] OR (clinical [tiab] AND studies [tiab]) OR treatment outcome [mh] OR treatment outcome [tw])) NOT (letter [pt] OR newspaper article [pt] OR comment [pt])
- 29. David L. Sackettet al. The practice of evidence based medicine means integrating individual clinical expertise with the best available external evidence from systematic research. … By best available external clinical evidence we mean clinically relevant research, often from the basic sciences of medicine, but especially from patient centred clinical research into the accuracy and precision of diagnostic tests (including the clinical examination), the power of prognostic markers, and the efficacy and safety of therapeutic, rehabilitative, and preventive regimens.
- 30. EBM: finding clinicalevidence (1) Diagnosis • Diagnosis : disease subheading ‘celiac disease’/dm_di • Diagnostic test accuracy study (2011) Used for original studies or systematic reviews which assess how accurately a test distinguishes humans or animals having a condition or disease from those who do not. Typically, the test under evaluation is called the index test and its results are compared to the results of the best available standard test (reference standard), which defines the condition or disease Case study: devices used in DTA studies for celiac disease
- 31. Searching for DTAstudies
- 32. EBM: finding clinicalevidence (2) Prognosis • Prognosis as Emtree term • Filters based on HIRU hedges (McMaster Univ.) * Max. specificity: prognos* OR survival Best balance: prognos* OR epidemiology:lnk OR follow-up Case study: prognosis for Parkinson’s disease * Ref: http://hiru.mcmaster.ca/hiru/HIRU_Hedges_EMBASE_Strategies.aspx
- 33.
- 34. EBM: finding clinicalevidence (3) Therapy • Drug subheading : drug therapy • Disease subheadings : drug therapy radiotherapy therapy surgery Safety • Drug subheadings : adverse drug reaction drug interaction • Disease subheadings : side effect complication Case study: complications arising following deep brain stimulation for Parkinson’s disease
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- 37. EBM: finding clinicalevidence (4) Rehabilitation • Disease subheading: rehabilitation ‘parkinson disease’/mj/dm_rh 529 results Prevention • Disease subheading: prevention 1. ‘myocardial infarction’/mj/dm_pc 4,359 results 2. aspirin/de 147,770 results 3. #1 AND #2 1,113 results
- 38. EBM: levels ofevidence systematic review meta-analysis case report case control study cohort analysis case study randomized controlled study editorial
- 39. EBM: finding guidelines Emtree . .........
- 40.
- 41.
- 42. EBM: other approaches Comparative Effectiveness Research (CER) • Emtree term: comparative effectiveness Added in 2010; approx. 2000 results/year from 2011 Cochrane Database of Systematic Reviews • Advanced limit: [cochrane review]/lim Over 11,000 reviews included in Embase since 2000
- 43. Summary Embase - supportingEvidence Based Medicine
- 44. • A Q&Awill be sent by email. • For more information and questions please contact bdtraining@elsevier.com • Our next Embase webinar is scheduled for Oct 25th, looking at drug safety and we will go deep into indexing and Nov 21st. • Go to http://www.embase.com/info/embase-webinars for all Embase webinars and archives. Please fill out the survey that appears on you screen after leaving the webinar.
Editor's Notes
- #3 For those of you who are already using Embase, we would like to remind you of the benefits of registering in the product. As well as receiving up to date webinar, release and event information, you may of course save your all-important searches or set up email alerts to continuously track the new information related to your search.And now, let’s hand over to Ian, welcome! Can you tell us about how Embase plays in role in EBM.
- #4 Medicine without evidence – a reminder of how life was before the EBM eraEBM definedEBM in Embase
- #5 Not so long ago a story unfolded describing a failure to find evidenceThis has become an iconic story and you may be familiar with itThe point I want to emphasize here is that the evidence WAS in fact there, but was difficult to find
- #6 With hindsight, here’s how the evidence could have been found – as described in the Infotoday storyYou had to know what terms to search, and where to look. This search retrieves 3 hits.The article shown describes a case report which, if discovered, would have warned of the possible lung toxicity of hexamethonium It is still covered exclusively on the OldMEDLINE portion of PubMed, not on MEDLINE.
- #7 Interestingly, you can do exactly the same search on Embase Classic, which is available via the Embase.com platform In this case the search retrieves 10 results.One of the hits is the same as we saw just nowon PubMed – but in this case it has an abstract, as do some 90% of records in Embase Classic. This is rather handy as it gives some context for the toxicity that is described.So: the point of this story is that evidence may be available, but difficult to find.
- #8 But what do we mean by evidence?Some 5 years before, a group of physicians working in Oxford, Canada and the US felt it was time to explain EBM to their peers. They published this paper in BMJ to explain what Evidence based medicine IS, and what it is NOT.Their goal was to show that EBM was not “cookbook medicine”, but a tool that could inform clinical decisions in day-to-day practice
- #9 A key point in the article is the link between EBM and clinical expertise, where evidence is obtained by systematic research.This means systematically looking for relevant evidence in the literature, an activity that has become codified in the preparation of systematic reviews.
- #10 The Centre for Evidence based Medicine, where David Sackett was based at the time, was by no means the only organization involved in the EBM movement.A few of the other organizations are depicted here – with the Cochrane Collaboration perhaps one of the best known, founded as it was on principles first set down by Archie Cochrane during and after the Second World War, in particular the idea of the Randomized Controlled Trial. Of interest is also the Guidelines movement, represented here by the Guidelines International Network, founded in 2002, and which has now grown to 88 member organizations worldwide, of which just a few are shown here. I won’t say much about Guidelines today, but the preparation and use of clinical guidelines is becoming increasingly important party of Evidence Based Medicine.
- #11 One of the areas of focus of guidelines is the differentiation of different levels of evidenceI’ll come back to this a little later, but just want to draw your attention to the fact that it is about much more than randomized controlled trials and systematic reviews, which are shown at the very top of the pyramid on the right.In many cases other kinds of study are appropriate, such as observational studies, illustrated by the tongue-in-cheek graphic about the parachutes.
- #12 So I would like to come back to the question posed by Sackett and his collaborators in that 1996 article, about identifying the best available external evidence from systematic research, and integrating that with clinical practice.Both steps are shown here, but we’ll leave clinical practice to the clinician and focus on the first two steps: formulating a clinical question + using EBM to systematically look for evidence.What I would like to show you today is how Embase can help you do that.
- #13 Now, as many of you will know the PICO method has been developed to help searchers, both information specialists or end users, to search systematically for evidence.PICO involves defining four different aspects of the search question, shown here. In practice, you may not need all four – it depends on the results.In the example I will show you I use just the first two and the last.
- #14 This example has been presented in a short video on YouTube which I won’t show you now (see the link here and on the Embase info site).The clinical question is whether there are any risks in giving antibiotics to a pneumonia patient who is already being treated with digoxin for congestive heart failure.
- #15 Jumping ahead, since this is a demo, this is the article we want to find.As you can see it describes the safety profile of moxifloxacin as a potent antibiotic against respiratory tract infections.
- #16 So, using the PICO approach, our clinical question can be parsed as shown here.The “C” is greyed out because it will only be used if needed to discriminate between large numbers of results.
- #17 Here we zoom in on the (O)utcome – identifying the risksThe key here is to link the drug and the subheading – in this example we have chosen drug interactionYoucan do this using the Drug Search form, as shown here. You don’t have to know the abbreviation used for drug interaction in the actual search query.
- #18 And here is an overview of the entire search strategyIn general, there are many strategies you can use to do a search like this. For example, you might limit the index term search in #1 and #2 to major descriptors, or add a subheading for therapy to pneumonia.I have chosen to keep the P part of the search in sets #1 to #3 broad and to focus specifically on possible drug interactions by using the drug subheading “drug interaction”, which I searched as shown in the previous slide, and here represented by dd_it, combined with the drugs of interest in sets #4 to #6.The final result in set #7 produces just #4 hits, and the second one is the article I showed you before.(click) … and here is part of the indexing, showing that digoxin has indeed been indexed as a major term linked to the subheading drug interaction.BTW, on PubMed this article has not been indexed with digoxin or with most of the drugs shown here. This illustrates how Embase’s in-depth drug indexing can help you identify evidence that is more difficult to find in PubMed and MEDLINE.
- #19 That was a short example of searching for evidence in Embase using a specific case. Here, I want to zoom out and look at the big picture: what does Embase have to offer the searcher looking for evidence.First and foremost there is the breadth of coverage. Embase now has almost 8,000 active journals and well over 25m records – 27m including Embase Classic going back to 1947. That includes all of MEDLINE as well as Articles in Press and In-Process records with indexing based on titles and abstracts, plus over 800,000 conference abstracts derived from over 3000 conferences since 2009 . This all means that if there is any evidence available, it has a pretty good chance of being in Embase.Then you have to find the evidence. Embase offers a wide range of tools to help you do that, beginning with in-depth indexing of drugs, diseases and medical devices, which have been recently expanded to cover over 1500 terms in Emtree. This is supplemented with extensive indexing of drug and disease subheadings, trade names and manufacturer names.And last but not least, Embase provides many specific terms focusing on levels of evidence and study types. Let’s look at some of these first.
- #20 Back in 1993, Embase was approached by the Cochrane collaboration with a strong recommendation to implement RCT as a new index term.We did that immediately, and also accepted an offer from Cochrane to identify RCTs and CCTs in Embase’s backfile, which were later used to update Embase’s indexing. As a result, Embase has unique coverage of non-English RCTs compared with MEDLINE, as I will show in a momentDuring the last 10 years and also at the instigation of Cochrane, we have added terms for Systematic Review, Controlled Clinical Trial, and finally in 2011 differentiated between study types, also known as publication types, and topic terms. I’ll explain that later.
- #21 In a paper from 2008 and also a couple of years ago at MLA, Carol Lefebvre, then at Cochrane, described some of these changes.In particular, she reported on some of the unique coverage of RCTs in Embase compared to MEDLINE.
- #22 Here are some of the results reported by Carol Lefebvre.As you see, these data are from 2005. I have now updated the data for the years 2011-2012
- #23 This is just a selection of the non-English language coverage of RCTs in Embase, and is important because it shows that even after the separation of topic terms, which as I mentioned I will explain in a moment, Embase outperforms PubMed for just about any language that you care to choose.
- #24 I promised to explain the topic terms, and here they are.As you can see there are 10 of these terms, and each corresponds to a study type, or publication type, as shown with the red arrow for RCT.The topic terms were introduced in Embase in 2011, in order to differentiate between study types, indexed when the article IS the primary report for an RCT, for example, and articles in which that term is only a topic that is discussed. Good examples of the use of topic terms are in letters and editorials.Before 2011, the distinction between publication types and topic terms was not made, so that searches for RCT (for example) retrieve a small proportion of records in which RCT is in fact only mentioned as a topic. Many of these can be filtered out by excluding non-original article types such as letters and editorials.
- #25 To support the use of key terms such as publication types, Embase has a system of check tags.The scope notes of several check tags are shown here – and an important point is that the scope notes were reviewed and in many cases updated in 2011.For example, the scope note for systematic review explicitly includes records which are identified as systematic reviews by the author. This is in order to minimize confusion when authors may use a slightly wider definition than we would have done.In the case of meta-analyses, the scope note explicitly states that they are not limited to clinical trials, which was previously the case. And as you see, clinical trials are themselves not exclusively human – a previous limitation – and the check tag “human” is itself defined in the widest possible way, now including articles about medical professionals, for example.In all these cases, the scope notes have been extended compared with earlier definitions in order to meet the expectations of users who told us they could not understand the earlier limitations – and, it must be said, with cooperation and advice from the Cochrane Collaboration.
- #26 Within Embase, you can access check tags related to EBM in many different ways.For example, in Advanced Search the Evidence Based Medicine group of limits shows some of the key terms, and in Emtree itself the term Evidence Based Medicine can be exploded to cover many of the same terms, and more.
- #27 The introduction of an Emtree term for systematic reviews in 2004 has been particularly welcomed by our usersAs you can see in this graphic, you can search for systematic reviews on both Embase and PubMed, and PubMed even has more.
- #28 The reason for this is shown here.On Embase, systematic review is indexed explicitly as a check tag.PubMed, on the other hand, does not actually index systematic reviews. Instead, they have an extensive hedge, or pre-programmed search behind the systematic review “subset”. As you can see, this is much broader than the Embase definition, including all kinds of terms such as meta-analysis, evidence-based-medicine, and review.
- #29 Here for example is the first page of a search on PubMed for systematic reviews limited to records indexed with “evidence based medicine”Basically it is up to you, the searcher, to decide what you want. Embase offers you the option of differentiating between all these terms and searching exactly what you want.
- #30 Let’s come back to the article written by Professor Sackett and his colleagues about Evidence Based Medicine: what it is and what it isn’t.In particular, let’s focus on the paragraph explaining what clinical evidence is, and do a deep dive into how we can search these aspects on Embase. So what I’ll do is show you some brief case studies for diagnosis, prognosis, therapy and safety, rehabilitation and prevention.
- #31 First off, let’s have a look at diagnosisOn Embase, you can search for diagnosis using a disease subheading as illustrated here.But what you can also do is use a fairly new check tag, introduced in 2011 following advice from and with the help of the Cochrane Collaboration: diagnostic test accuracy study. The scope note is shown here.In the case study I’ll show a search using this check tag.
- #32 Here it is: as you may know, diagnosis of celiac disease is not straightforward, and patients may experience symptoms for years before they are diagnosed.In this search, I have simply looked for recent articles – remember that this check tag was only introduced in 2011 – which have studied diagnostic test accuracy in celiac disease.I have followed this up with a medical device search to find articles which mention devices in this connection. This makes use of the recent expansion of the medical devices tree in Emtree – as you can see over 1.3 million articles in Embase, nearly 5%, mention a medical deviceThe overall result is 3 articles which if this were a real search you could check out to find out more about the use of capsule endoscopy in diagnosing celiac disease.It’s important to note is that there are many ways to look for evidence: this is just one way, and other approaches may identify other articles – especially from before 2011.
- #33 My second example is about prognosisIn this case, Embase has no subheading. Instead, it is always possible to use the Emtree term.But as an alternative, you can have a look at how third parties have addressed this issue. For example, at the Health Information research Unit in McMaster University, hedges have been proposed for exactly this situation.The URL at the bottom describes many hedges that are applicable to Embase.As an illustration, I have chosen two which can be used for prognosis: a so-called maximum specificity hedge for high precision, … and a hedge which offers the best balance between specificity and sensitivity.The lnk field label, by the way, identifies the use of a term – here epidemiology - as a subheading
- #34 Here is a search illustrating the use of these hedges.You’ll notice that I have chosen to link the epidemiology subheading directly to Parkinson’s disease. And BTW, the free text searches on prognosis, survival and follow-up automatically search words in ALL fields including the indexing.
- #35 My third case covers therapy and safetyIn this case there are many subheadings, depending upon what you need. For example, for treatment you can choose between drug therapy, radiotherapy, therapy (i.e. other kinds of therapy) and surgery. For all these subheadings, scope notes are available in Emtree.For safety, one of the options is the subheading complication, which is used for disorders or symptoms which arise as a complication of a pre-existing disease or medical procedure other than drug treatment. This is the subheading I have chosen to illustrate safety-related clinical evidence, also in association with Parkinson’s disease
- #36 The question addressed in this case is the following: what complications can arise when Parkinson’s disease is treated by deep brain stimulation, and are any of those associated with the medical devices used?Here, complication is searched as a “free” subheading because it is not known in advance what the complication might be. And as for one of the previous searches, an explosion search on medical device retrieves all articles which mention any medical device.Among the 47 articles retrieved is the one on the following slide.
- #37 In this article, postoperative complications are described which are associated with deep brain stimulation of various conditions including Parkinson’s diseaseThis is exactly what we were hoping to find, and illustrates the power of Embase indexing for zero-ing in on this kind of evidence
- #38 And finally I want to show how the remaining two kinds of evidence may be searched on Embase.In both cases you can use subheadings: for rehabilitation and prevention respectively.In the second case, there are rather too many hits to warrant reading them all. This is a good example where the “C” of PICO can come in handy: Comparison
- #39 As you will recall, one of the features of Evidence Based Medicine is the importance of levels of evidence.To search for levels of evidence you can use the study types that we have looked at so far, such as systematic review and RCT. However, Embase provides you with additional optionsOn the left of the search screen a number of search filters are shown, one of which is called “study type” If you open this up, you see a list of all terms available from Embase’s Types of Article or Study facet which have been used in the records found by this search(click) These include not only the terms we have seen so far, but also additional options such as cohort analysis and practice guideline This provides a powerful tool to continue your search and pinpoint those studies carried out at the level of evidence that you are interested in
- #40 Now, one of the terms we just saw was practice guideline.I would like finish today by showing you that Embase contains quite a bit of useful information on clinical guidelines
- #41 For example, we could have used the term practice guideline to limit the search we did earlier on deep brain stimulation of Parkinson’s disease to those records mentioning relevant guidelines, as shown here in set #5.An even more precise approach is to limit the word “guideline” to the title, on the basis that such records are likely to present the actual guidelines.If you do this here you find 6 results.
- #42 These are the first three results from this search And as you see there are some extremely relevant resultsIn the absence of a worldwide compendium of clinical guidelines, a search like this can provide a good snapshot of some of the available guidelines, which you most likely would want to supplement by looking at other sources such as the National Guideline Clearinghouse in the USA, the National Institute of Clinical Excellence (NICE) in the UK, or similar bodies in many other countries, as documented for example by GIN, the Guidelines International Network.
- #43 There’s just time to mention a couple of other approaches to finding Evidence in Embase.These are: Comparative Effectiveness Research which is strong particularly in the USA, and systematic reviews reported by the Cochrane Database of Systematic Reviews.In both cases Embase offers options to search the relevant data, as illustrated here.
- #44 So I hope you will agree that Embase provides a useful toolkit that can help you find evidence for the clinical questions you are interested in or asked to report on.(click) (click) … Whoever you are, librarian, information specialist, research scientist, physician or end-user: Embase has a tool for you !
- #45 We have come to the end of our Embase webinar. Thank you for attending and thank you Ian for this fascinating overview of Embase and EBM. You will receive a link to the webinar calendar in a follow-up email and please feel free to register for as many Embase webinars as you wish. And of course send it to your colleagues. When you leave the session, a survey will pop up. Please fill out what your thoughts are regarding this webinar and so help us to improve future webinars. Besides this you will receive the Q&A by e-mail shortly and we will place the recording of this session on the Elsevier training desk website and Embase YouTube channel. Many thanks again, good luck with further exploring Embase and we hope to meet you again soon.