Effective search of bibliographic databases .   

Dr Tarek AminProfessor of Public Health

Cairo Universityamin55@myway.com

Objectives

1 -Orienting the audience of the model for information searching using medical bibliographic databases .

2 -Identify the appropriateness of different medical databases

3 -Orienting the audience about the effective strategy for searching bibliographic databases .

Introduction/rationale

o The rapid increase in medical information poses a challenge for keeping up with the latest developments in the field.

o Information searches can be difficult without a basic knowledge of the way information is organized and indexed.

o In preparing scientific studies and in making clinical decisions, the key issue is to effectively scrutinize previous literature.

o That is why familiarity with medical information sources and the ability to use them effectively is important (1)

Gore G. Searching the medical literature. Inj Prev 2003 Jun;9(2):103–104.

Introduction (cont.)

o Estimated that 20,000-30,000 journals published on medicine and health.

o Printed journals are being increasingly replaced by e-journals

o The amount of medical information is doubling every 5 years

Mattox D. Welcome to Archives CME. Arch Otolaryngol Head Neck Surg 2000;129(7):914.

The information search process

o Medicine is now a multidisciplinaryo Overwhelming bibliographic

databases with advanced technology.o Hard to find the specific and relevant

information o Information search is seldom a simple

one-way process.

Lِohِnen J etal. A guide for medical search. Int J Circumpolar Health 2009; 68(4):394-404

Effective and relevant information

The experience of the searcher :

-Knowledge of sources ,

-Systems , -Search language

and -Use of key words

Databases : -No. of journals.

-Quality of indexing

-Limitations in content description.

Information search model.Definition of research problem and question formulation

Choice of databases: Factors affecting the choice:- Databases available- Up-to-date information on the database- Coverage in terms of time and content- Database’s indexing practicesMedline (Ovid), PubMed, Web of Science, Scopus, PsycINFO and EMBASEFormulation of search strategy- Key concepts, relationships between concepts- Free word searches and thesaurus- Boolean operators (AND, OR, NOT)- Search limits (e.g. ,year, publication type)

Conducting the search and Evaluation- Search terms are entered- Assessing relevance of the search and the results- Possible decision-making in case of clinical problem-solving- A reformulation of a search when needed

McDonald S, Taylor L, Adams C. Searching the right database: a comparison of four databases for psychiatry journals. Health Libr Rev 1999;16(13):151–156

1 -Defining the research problem and formulating the questions.

What is the exact topic? What purpose will the information play? Which issues are included and/or

excluded? What is essential information and what

is already known on the topic? Is the needed information general or

scientific?

1 -Defining the research problem and formulating the questions.

Background reading is essential Make a plan Quick search is important to explore: – terms, - concepts – keywords The PICO model: P patient I Intervention C control O outcome

2 -Choice of databases

Bibliographic databases are extensive compilations of references and documents.

Reference is the information included in the document, such as information on authors, abstract, journal title and year of publication (7).

Many bibliographic databases include a link to the full text.Corrall C, Wyer P, Zick L, Bockrath C. How to find evidence when you need it, part 1: databases, search

programs, and strategies. Ann Emerg Med 2002;39 (3):302–306.

In searching medical bibliography:

Multiple (more than one databases should be considered)

The extent of database coverage should be considered.

Different databases use different keyword systems and different levels when indexing material.

A thesaurus is affected when there is rapid development in a field and recently introduced terms and concepts in the literature are not included in the vocabulary quickly enough (nanotech.).Indexing refers to a description of documents using certain rules,

vocabularies and key words. Thesaurus is a special vocabulary where the relations between terms are expressed in a standardized manner.

Key medical bibliographic databases for search CINAHL Elsevier

ScienceDirect

EMBASE (Excerpta medica)

LILACSMedline (Ovid)

Nursing and allied health sciences - About 1.5 million references to articles, congress publications and academic dissertations since 1982.- About half of thereferences are found in the PubMed database.

Maintained by Elsevier B.V. containing bibliographic data and full texts.- About 6.75 million articles up to 1995 and 2.75 million articles from 1994 onwards.- Covers 25% of full texts and bibliographic data in science, technology and medicine in the world

Biomedical andpharmacologicalDatabase produced by Elsevier B.V.- Over 11 million records from 5,000 journals from 1974 onwards.- More than 500,000 references and abstracts are added to the database each year.

Open-access health science database of BIREME Systems in Spanish, Portuguese and English.- About150,000 records, such as books, congress and conference publications, and articles from 670 well-known medical journals .

Bibliographic database published by Ovid Technologies.- About 13 million references on medicine and related fields from 4,800 journals since1966.- An increasing number of references contain a link to freely available full text

Key medical bibliographic databases for search PsycINFOPSYNDEXPubMedScopusWeb of

Science- A bibliographicPsychological database provided by EBSCO Publishing.- 2.3 million references and abstracts from year 1887.- References from sources such as articles, books and academic dissertations in all fields related to psychology.

- A bibliographicpsychological database from the German speaking countries.- All areas of psychology and related behavioral and social sciences from 1977, audiovisual media from 1932, and tests from 1945.

- A free service of the U.S. National Library on Medicine through which also Medline is available.- About 21 million references from the 1950s onwards.- Includes new references that are not yet indexed in Medline.- Links to full text

- Bibliographic database of Elsevier B.V.- About 27 million abstracts, 230 million references, 200 million scientific www-pages, over 12,850 journals, 535 of which are OA journals.- Covers the Medline (Ovid) database, including full text links when applicable.

Bibliographic database of Thomson Reuters.- Databases accessible from 1986 on: Science Citation Index Expanded, Social Science Citation Index,Arts & Humanities - 850,000 references including links to full texts when applicable.

Access to databases

Bibliographic databases are commercial

products, which is why not all databases are licensed by individual research organizations.

Freely accessed bibliographic databases.

PubMed www.pubmed.gov Directory of Open Access Journals

www.doaj.org PubMed Central www.pubmedcentral.nih.gov . The Public Library of Science (PLoS)

www.plos.org BioMed Central (BMC) www.biomedcentral.com Different OA repositories, like the Directory of

Open Access Repositories OpenDOAR www.opendoar.org and CiteSeer (www.citeseer.ist.psu.edu).

Search engines and portals

The most popular Internet search engine, Google www.google.com

Google Scholar www.scholar.google.com Google books, to search only books

www.books.google.com Google Scholar makes it possible to

search for essays, presentations, books, abstracts and articles in various fields and from different sources, such as academic publishers, associations and other scientific organizations.

Search engines and portals

Other medical search engines and link collections include:

Sum-Search www.sumsearch.uthscsa.edu , Scirus www.scirus.com , Medical-Matrix www.medmatrix.org

The medical pages of Intute www.intute.ac.uk/healthandlifesciences/medicine .

3 -Practical steps for searching

1. Get your search question clear The trickiest part of setting up a search,

basically the question is ‘what am I actually looking for?’. You need to be clear about what search terms you are going to use to ask your question.

Take the topic below as an example Does parental smoking is linked to pediatric

ear infections?

Consider

o Not using natural language (verbs, propositions)

o Concentrate on nouns, keywords and concepts

o Take care of alternatives (synonymous)

o Search engines can not recognize some terms (computer, internet)

2-Putting your terms together

Start by considering possible term variations. Generally, bibliographic databases will only locate exactly what you tell them to find.

Sources of term variation you should consider: Plurals – searching for ‘bacteria’ (plural) won’t find ‘bacterium’

(singular). UK/US spellings – searching for ‘analyze’ won’t find ‘analyse’. Numbers –2 or two or II Synonyms – The same hormone may be known as adrenaline

or epinephrine. Abbreviations – PCR or Polymerase Chain Reaction

Some databases have built in thesauri which help them find some term variations automatically.

For example, searching for ‘Woman’ on PubMed will search for ‘Women’ as well.

Using the wild card*

In Pubmed the asterisk ‘*’ will truncate words:

Bacteri* Finds: Bacteria, bacterial, bacterium, bactericidal etc.

In some databases like Scopus and Web of Science you can allow substitution of single characters to help deal with differences in spelling –

Analy?e Finds: Analyze and Analyse

Boolean operators

Boolean logic operators are named after the British mathematician George Boole, they are used to create relationship between search topics or keywords.The basic Boolean logic operators are: AND, OR, and NOT.

These operators can be used to narrow or broaden the searches.

Boolean operators

OR: This search will retrieve articles

that are about either “heart valve disease” or “myocardial infarction” (similar terms).

MIHeart valve

disease

OR

OR ALWAYS BROADENS A SEARCH

Boolean operators

AND:This search will retrieve articles

that are about “heart valve disease” and “diabetes.”

Heart valveDisease Diabetes

AND

AND ALWAYS NARROWS A SEARCH

Boolean operators NOT: This search excludes all records that

have the term “diabetes” in them. if an article compares heart valve disease with diabetes you will lose it from your search. therefore, use not with restraint and be aware of the consequences.

NOT ALWAYS NARROWS A SEARCH

3-Set your limits

You can refine your results down further by applying limits to your search.

PubMed lets you limit your search by many criteria including date of publication, document type and language.

Example: Published in the last: 5 years. Type of Article: Clinical Trial. Languages: English

Then ask the following questions to rate the quality other websites/engines not bibliographic databases (a yes implies better quality).

Questions YesNo

Is the site put together by a known institution or organization? (clue from the last few letters e.g. gov. edu.)

Are the objectives of the site clearly educational? (are they advertising or selling products? Patient education? Information about services?)

Are there sections that explain the various goals? (e.g. a patient section, and a research section, for a hospital)

Is there a search engine for the site itself, to locate information?

Then rank the quality of the website (other than bibliographic databases by giving a score form 1 to 5 (excellent) in the categories below.

Elements 12345

1Responsive (quick connection)

2Goals are clear

3Distinguishes fact form opinion

4Current (look for the date the site was last updated)

5Visual impact

6Easy to find information

7Connects to useful sites

8Addresses at least 50% of your learner’s needs

9Provides justification for opinions or views (gives evidence)

10Allows for communication with a web master or a consultant.

Searching for evidence

Birch D, Eady A, Robertson D, De Pauw S, Tandan V. Users’ guide to the surgical literature: how to perform a literature search. Can J Surg 2003;46(2):136–141

5 S pyramid

Searching for evidence:

Pubmed using clinical queries www.ncbi.nlm.nih.gov/entrez/query/static/clinical.shtml This feature is also included in Medline

(Ovid), EMBASE, PsycINFO and CINAHL (Ebsco).

The Cochrane Library: www.cochrane.org

Searching for evidence

Evidence-based information at Seek www.shef.ac.uk/seek ,

EBM Guidelines ebmg.wiley.com/ebmg The TRIP database (

www.tripdatabase.com/index.html), SUMsearch: http://sumsearch.uthscsa.edu/ BMJ Clinical Evidence:

www.clinicalevidenceorg/ceweb/index.jsp DynaMed www.ebscohost.com/dynamed

Searching for evidence

UpToDate http://www.uptodate.com is an evidence-based, peer-reviewed

information resource. PIER: The Physicians’ Information and

Education Resource http://pier.acponline.org/index.html?jhp provides authoritative, evidence-based

summaries.

Useful Web Sites for Physicians.

Evidence-based Medicine.Cochrane Library:

www.cochrane.orgClinical evidence (Free):

www.clinicalevidence.comJournals:

www.evidence-basedmedicine.comEvidence based guidelines (Free access):

www.guideline.gov.Best treatment :

www.besttreatment.orgDynaMed:

www.dynamicmedical.com

Useful Web Sites for Physicians.

Data base other than Pubmed and free:

www.pubmedcentral.com

www.biomedcentral.com

www.sumsearch.uthscsa.edu/

Useful Web Sites for Physicians.

http://emedicine.medscape.com

http://www.biomedcentral.com/

Useful Web Sites for Physicians.

General Web Sites for Clinical Educators

www.acgme.org

www.helath.gov/healthypeople/

www.uchsc.edu/CIS

www.aamc.org

www.acog.org

www.cdc.gov

Useful Web Sites for Physicians.

General Web Sites for Clinical Educators

www.acgme.org

www.helath.gov/healthypeople/

www.uchsc.edu/CIS

www.aamc.org

www.acog.org

www.cdc.gov

Useful Web Sites for Physicians.

Physicians Training Web Siteswww.APGO.ORG/MEMEBERSHIP/CURRICULUM.CFM

www.mcphu.edu/institutes/iwh/nawhme/academy.htmlwww.mero.lib.wfubmc.edu/tfwhcepub/comparecenters.htmwww.aafp.com/edu/guide/rep282.html

Useful Web Sites for Physicians.

Sites For Clinical Informationwww.ideallibrary.com/links/toc/ebogwww.nof.orgwww.nams.orgwww.nlm.nih.govwww.cochrane.orgwww.ahcpr.govwww.fis.utoronto.ca/phd/marton/womenhl.htm

Useful Web Sites for Physicians.

Public Healthwww.who.intwww.apha.comwww.cdc.govwww.ginevafoundation.comwww.papha.org

Useful Web Sites for Physicians.

Clinical Teaching

www.aamc.org/meded/start.htmhttp://futurehealth.ucsf.edu/hpsisn.htmlwww.medinfo.ufl.edu/cme/inethttp://omie.med.jhmi.edu/lecturelinks/

Thank you