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UNDERSTANDING A RESEARCH ARTCILEA.THANGAMANI RAMALINGAM
ObjectivesCOMPONENTS OF AN ARTICLELEVELS OF EVIDENCEHOW TO READ AN ARTICLECOMMON SIGNS OF DUBIOUS DATA
Original article – information based on original research
Case reports – usually of a single case Technical notes - describe a specific technique or
procedure Pictorial essay – teaching article with images Review – detailed analysis of recent research on a
specific topic Commentary – short article with author’s personal
opinions Editorial – often short review or critique of original
articles Letter to the Editor – short & on subject of interest
to readers
Effective Medical Writing. Peh WCG &, NG K H Singapore Medical Journal 2008 49(7) 522 smj.sma.org.sg/4907/4907emw1.pdf (accessed 05 November 2013)
I.COMPONENTS OF AN ARTICLE
The Usual Sequence(Abstract and Key
Terms)IntroductionMethodsResultsDiscussionConclusionAcknowledgements
(References)
Most journals use a conventional IMRD structure: An abstract followed by Introduction, Methods, Results, and Discussion
Features of AbstractsAbstracts usually contain four kinds of
information: Purpose or rationale of study (why they did
it) Methodology (how they did it) Results (what they found) Conclusion (what it means)
Features of IntroductionsIntroductions serve two purposes: Creating readers’ interest in the subject providing them with enough information to
understand the article
Features of MethodsThe Methods section tells the reader what
experiments were done to answer the question
Features of Results and DiscussionThe Results section contains results—
statements of what was found, and reference to the data shown in visuals (figures and tables). Normally, authors do not include information that would need to be referenced, such as comparison to others’ results.
The Discussion also functions to provide a clear answer to the question posed in the Introduction and to explain how the results support that conclusion.
II.LEVELS OF EVIDENCE
Systematic review
Randomized controlled
trials
Cohort studies Case series,
Case reports
Ideas opinions
Levels of Evidence
Evidence grading1989 USPSTF(United States Preventive
Services Task Force )5 levels of evidence
Other systems:CEBMACCAAFP (SORT)GRADE
Grade Definition Suggestions for Practice
A The USPSTF recommends the service. There is high certainty that the net benefit is substantial.
Offer or provide this service.
B The USPSTF recommends the service. There is high certainty that the net benefit is moderate or there is moderate certainty that the net benefit is moderate to substantial.
Offer or provide this service.
C The USPSTF recommends against routinely providing the service. There may be considerations that support providing the service in an individual patient. There is at least moderate certainty that the net benefit is small.
Offer or provide this service only if other considerations support the offering or providing the service in an individual patient.
D The USPSTF recommends against the service. There is moderate or high certainty that the service has no net benefit or that the harms outweigh the benefits.
Discourage the use of this service.
I Statement The USPSTF concludes that the current evidence is insufficient to assess the balance of benefits and harms of the service. Evidence is lacking, of poor quality, or conflicting, and the balance of benefits and harms cannot be determined.
USPSTF (as of May 2007)
GRADE (a work in progress) GRADE classifies recommendations as strong or weak Strong recommendations
mean that most informed patients would choose the recommended management
and that clinicians can structure their interactions with patients accordingly Weak recommendations
mean that patients’ choices will vary according to their values and preferences,
and clinicians must ensure that patients’ care is in keeping with their values and preferences
Strength of recommendation
determined by the balance between desirable and undesirable consequences of alternative management strategies, quality of evidence, variability in values and preferences, and resource use
http://www.gradeworkinggroup.org
SORT
Patient or disease oriented?Disease-Oriented Outcomes.
Intermediate, histopathologic, physiologic, or surrogate results
Examples: blood sugar, blood pressure, flow rate, coronary plaque thickness
May or may not reflect improvement in patient outcomes.
Patient-Oriented Outcomes. Outcomes that matter to patients and help
them live longer or better livesExamples: including reduced morbidity,
reduced mortality, symptom improvement, improved quality of life, or lower cost
III.HOW TO READ AN ARTICLE
1. How are papers organized?2. How do I prepare to read a paper,
particularly in an area not so familiar to me?
3. What difficulties can I expect?4. How do I understand and evaluate the
contents of the paper?
How are papers organizedSkim the article and identify its structure.
How do I prepare to read a paper Read the title and the
abstractChoose to read the
background in a review or textbook, as appropriate.
If you are very familiar with the field, the introduction can be skimmed or even skipped.
Interested in a particular point given in the abstract often skips directly to the relevant section of the results
Interpretation of the findings
Most scientists read the abstract first.
What difficulties can I expect?One major problem is that many papers are poorly
written.Second, papers are often cluttered with a great deal of
jargon.Third, the authors often do not provide a clear road-
map Many authors do not clearly distinguish between fact
and speculationOverstate the importance of their findings, or put a
speculation into the title in a way that makes it sound like a well-established finding("assertive sentence title“)
Distinguish main points.
How do I understand and evaluate What questions does the paper address? What are the main conclusions of the
paper?What evidence supports those conclusions? Do the data actually support the
conclusions? What is the quality of the evidence? Why are the conclusions important?
Actions to be takenSkim the article without taking notesRead the “Materials and Methods” and
“Results” sections multiple times.Generate questions and be aware of your
understandingTake notes as you read. Draw inferences.
Write a draft of your summary
.
A Critical Review and Assessment of the Article Include a summary as well as your own analysis and evaluation
of the article. Know the article thoroughly. Do not include personal opinions. Be sure to distinguish your thoughts from the author’s
words. Focus on the positive aspects and what the author(s) of the
study learned. Note limitations of the study at the end of the essay o Do the data and conclusions contradict each other? o Is there sufficient data to support the author’s generalizations? o What questions remain unanswered? o How could future studies be improved?
IV. DUBIOUS DATABlundersSources(who counted and why)Definitions(what did they count)Measurements(how did they count)Packaging(what they are telling)Rhetoric(what they want us to think)Debates
COMMON SIGNS OF DUBIOUS DATASlippery decimal point(eg:4%-1990,7%-2000)Botched translations(25% increase in risk)Misleading graphsCareless calculationBig round numbers(bird window deaths)Hyperbole(using superlatives)Broad definitionsOdd units of analysisConvenient time frame ,selective comparisions,
misleading samples &statistical adjustmentsShort term benefits are converted to longterm
benefits
NewsNature 418, 113 (11 July 2002) | doi:10.1038/418113aDubious data remain in print two years after
misconduct inquiry Alison Abbott & Johanna Schwarz Many of the 94 scientific papers listed two
years ago by a German inquiry as likely to contain manipulated data have yet to be retracted from the literature, Nature has discovered. The suspect papers were identified during a high-profile investigation into misconduct in German cancer research, the results of which were published in June 2000.
ResourcesEffective Medical Writing. Peh WCG &, NG K H
Singapore Medical Journal 2008 49(7) 522 smj.sma.org.sg/4907/4907emw1.pdf
How to read a scientific article. Mary Purugganan & Jan Hewitt, Rice University www.owlnet.rice.edu/~cainproj/courses/HowToReadSciArticle.pdf
How to read a scientific paper. John W. Little & Roy Parker--University of Arizona www.biochem.arizona.edu/classes/bioc568/papers.htm
How to read and review a scientific journal article. Duke University Writing Studio twp.duke.edu/uploads/media_items/scientificarticlereview.original.pdf
ResourcesAbout EBMCentre for Evidence-
Based Medicine (http://www.cebm.net/)
Agency for Healthcare Research and Quality (http://www.ahrq.gov/clinic/epcix.htm)
Evidence sources DynaMed (
www.dynamicmedical.com/)Essential Evidence Plus (
www.infopoems.com/)Cochrane Library (
www.cochrane.org/)Database of Abstracts of
Reviews of Effectiveness (www.crd.york.ac.uk/crdweb/)
FPIN (www.fpin.org/) Clinical Evidence (
www.clinicalevidence.com/)