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WORK ON COMPUTERSWinter Semester : List of

Topics1. Medical literature as a resource for

evidence based medicine. An overview. 2. Biomedical literature resources and

hierarchy of evidence.3. MEDLINE - the most important biomedical

database. PubMed online training. 4. MEDLINE - sample searches. Search

strategy tips, Boolean operators, working with search results. MeSH, links to fulltext articles.

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CLINICAL QUESTION FOR TODAYAuthor: Prof. V. Mihál, MD, PhD.

Vaccination for prevention of otitis media

in children

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Topic 1: ConsolidationGoogle Search & Document Types

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Self-study Assignment 1 Identify types of first 40 documents,

eg. Company websites Journal articles

Fulltext version Bibliographic record only Bibliographic record + abstract

Database Educational material (universities, professional societies) Patents Patient information Library catalogs Business information (eg.pharmaceutical companies) Others (specify)

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Quality of Internet Resources eEurope 2002: Quality Criteria for

Health related Websites

Communication from the Commission to the Council, the European Parliament, the Economic and Social Committee and the Committee of the Regions

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European Commission„Quality Criteria for Health Related Websites“Published 2002

1. Transparency and Honesty

Provider of site - including name, physical address and electronic address of the person or organisation responsible for the site

Purpose and objective of the site

Target audience clearly defined (further detail on purpose, multiple audience could be defined at different levels).

Sources of funding for site (grants, sponsors, advertisers, non-profit, voluntary assistance).

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European Commission„Quality Criteria for health Related Websites“

2. Authority

Clear statement of sources for all information provided and date of publication of source.

Name and credentials of all human/institutional providers of information put up on the site, including dates at which credentials were received.

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European Commission„Quality Criteria for health Related Websites“

3. Updating of information

Clear and regular updating of the site, with date of up-date

clearly displayed for each page and/or item as relevant.

Regular checking of relevance of information.

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European Commission„Quality Criteria for health Related Websites“

4. Privacy and data protection

5. Accountability (user feedback, trustworthy linking to other websites, editorial policy)

6. Accessibility (general findability, searchability, readability, usability, etc.).

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Journal Articles : Categories Original articles / clinical research results

Randomized controlled trials Cohort studies Case reports + case series Editorials, letters to editor, comments….

Reviews / secondary research Critically appraise contents & methodology of published

original studies (>2) to help readers orientate in the never-ending information explosion…..

12Pyramid of Evidence

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Original ArticlesRandomized Controlled Trials

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Original ArticlesRandomized Controlled Trial : ExampleFireman B. et al. Impact of the pneumococcal conjugate vaccine (PCV) on otitis media. Pediatric Infectious

Diseases Journal 2003; 22:10-16.Institution:Kaiser Permanente Vaccine Studies Center, Oakland, CA, USA.

Objectives:To examine impact of PCV on incidence of otitis media; to assess if effectiveness of the vaccine wanes after after age 24

months and varies by race, sex or season. Design, setting, participants:

1995 – 1998 37 868 children were randomized (allocated by random) to receive

PCV vaccineOR Control vaccine

Follow-up until April 1999 Intervention:

Primary series at 2, 4 and 6 months; booster at 12 to 15 months. Results:

Control children averaged 1.8 otitis visits/year PCV vaccinees had fewer otitis visits in every age group, sex, race and season. PCV vaccine reduced

otitis visits by 7.8% antibiotic prescriptions by 5.7%.

Conclusions:In children followed up to 3.5 years, PCV provided a moderate amount of protection against

ear infections while reducing frequent otitis media procedures by greater maounts.

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Original ArticlesCohort Studies

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Original ArticlesCohort Study : ExampleT.Heikkinen et al. Influenza vaccination in the prevention of acute otitis media in children.American Journal of Diseases of Children 1991; 145(4):445-448.Institution: Department of Pediatrics, University of Turku, Finland.

Objectives:We studied a new approach to the prevention of acute otitis media through the administration of

influenza vaccine Participants:

Group of vaccinees: 187 day-care center children aged 1 to 3 years before the influenza A epidemic of 1988-1989.

Comparison group: 187 unvaccinated children of similar age and background. Follow-up:During the 6-week study period, influenza A infection was diagnosed

in 5 (3%) of 187 vaccinees, and in 29 (16%) of 187 controls.

Acute otitis media developed in 3 (60%) of 5 vaccinees with influenza A infection compared with

18 (67%) of 27 controls (excluded were two children with a double viral infection). Outcome:

The incidence of acute otitis media associated with influenza A was reduced by 83% in the vaccinees. The total number of children with acute otitis media in the vaccine group was 35, compared with 55 in the control group, disclosing a 36% reduction among the vaccinees.

Conclusions:Influenza vaccination decreased the incidence of acute otitis media in children during an

influenza A epidemic, suggesting also that other vaccines against respiratory viruses may be an effective way to reduce the incidence of acute otitis media.

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Original ArticlesCase Reports + Case Series

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Review ArticlesDefinition „Review articles in medical journals summarize large

amounts of information on a particular topic; …..a useful and popular source of information for doctors. ……some review articles reflect the personal opinions of the

author more than the body of knowledge about a topic. Experts have proposed guidelines for how authors should

write review articles in order to avoid personal bias. ……..authors should address a focused question, describe how they searched for and evaluated

information, identify gaps in knowledge, estimate risks and benefits of recommended treatments.“

Annals of internal Medicine 1999;131(12):947.

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Types of Reviews

Traditional („narrative“)

Systematic + Meta-analysis (selection of articles according to pre-

determined criteria; statistical analysis)

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Traditional („Narrative“) Reviews Frequently found in many journals Often broad in scope „Book chapter“ Usually based on incomplete data Do not use systematic methods

identify assess synthesize

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Systematic Reviews Main Features Focus on a specific clinical question and

conduct an extensive literature search to identify studies with sound methodology.

Studies are reviewed, assessed, and the results summarized according to the pre-determined criteria of the review question.

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Systematic Reviews & Meta-Analysis

Statistical methodsStatistical methods

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Bibliographic Databases„Pathway to Journal Articles“ MEDLINE / PubMed

Service of US National Library of Medicine

URL http://www.pubmed.com is an easy and free place to search for answers to

foreground questions, and it offers links to a growing number of free full-text articles. Size >18 million records Retrospective since 1950 until present LinkOut feature --- access to fulltext articles through external providers (publishers, info brokers)

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Use of Boolean Operators Allows you to combine search terms to

better focus your search AND: Combines terms to limit your search as both(all)

concepts must be present in all retrieved articles. Example: otitis media AND vaccin*

OR: Widens your search as either term can be present in all retrieved articles

Example: otitis media OR middle ear inflammation NOT: Limits your search by excluding a concept as one

term must be present and the second term must not be present

Example: otitis media NOT chronic

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What is Truncation / Wildcard PubMed finds all terms that begin with a

given text string Represented by the asterisk (*),

sometimes referred to as a „wildcard“.

Example vaccin*

PubMed retrieves: vaccine, vaccines, vaccination, vaccinated, vaccinee(s),,,,,,,,,

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PubMed Search StrategyProblem/Disease

http://www.pubmed.com

Step 1 otitis media OR middle ear inflammation*

OR middle ear infection*

Limits: Title

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Enter One or More Search Terms &Use Features Tabs

Click onLimits

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Choose Limits : Title

2.

Select Title

3.

Press Go

1.Scroll Down

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Step 1 : Results otitis media/title Display Format : Summary

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Display Format : Summary Record Structure

Author(s)Schmelzle J, Birtwhistle RV, Tan AK. Article titleAcute otitis media in children with

tympanostomy tubes. JournalCan Fam Physician. 2008 Aug;54(8):1123

VolumeIssue Page(s)

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PubMed Search StrategyIntervention/ExposureStep 2

vaccin*

Limits: Title/Abstract

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Step 2 : Clear Search Box + Limits Box

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Enter New Search Term(s), Choose Limits

2.

Select Title/Abstract

3.

Press Go

1.Scroll Down

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Step 2 : Results vaccin*/Title-abstractDisplay Format : Summary

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PubMed Search StrategyCombine SearchesStep 3#1 AND #2

Choose additional limits: Ages

Birth-23 months Type of article

eg. Randomized Controlled Trials Etc.

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Step 3 : Clear Search Box + Limits BoxClick on History

Click on History

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Step 3: HistoryClick Query # for More Options

Click query # for more options.

2. Click on Preview

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Combine Searches, eg. #1 AND #2

Click on Preview

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Results of Step 3: otitis media x vaccin*Choose Age Limits

Click on Limits

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Age LimitsBirth-23 months; Pre-school 2-5 years

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Age Limits Applied: Results

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PubMed

To Be Continued ………………