Middle East Fertility Society Journal (2010) 15, 294–295

Middle East Fertility Society

Middle East Fertility Society Journal

www.mefsjournal.comwww.sciencedirect.com

EVIDENCE BASED MEDICINE CORNER

From evidence-based medicine to evidence-based practice:

Is there enough evidence?

Ahmed Nasr *

Women’s Health Center, Department of Obstetrics & Gynecology, Faculty of Medicine, Assiut University,P.O. Box 1, 71516 Assiut, Egypt

Received 1 September 2010; accepted 2 September 2010Available online 2 October 2010

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KEYWORDS

Evidence-based medicine

(EBM);

Evidence-based practice

(EBP)

Tel.: +2 010 5212140/088 21

-mail address: a_nasr02@lyco

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Abstract Undoubtedly, the ultimate intention of EBM is to provide a theoretical background on

which evidence-based practice (EBP) is founded. However, does reliance on EBM dictums always

leads to an equally satisfying EBP? Are they two sides of the very same coin? Are EBM-drawn con-

clusions too hard-and-fast to defy any argument, reasoning, challenge or questioning? Such ideal-

ism is still, unfortunately, out of reach. It is prudent to ask ourselves one important question: is

evidence-based medicine really evidence-based? If so, how could we explain the discrepancies and

inconsistencies existent between EBM and EBP? How did such discrepancies arise?� 2010 Middle East Fertility Society. Production and Hosting by Elsevier B.V. All rights reserved.

Long thought of as a novel concept that has acquired con-siderable popularity over the last few decades, medical practicebased on evidence is an antiquated stratagem. Its roots are

traced to the 11th century where evaluation of the efficacy ofmedical interventions was cited in Avicenna’s The Canon ofMedicine (1). Over the years, interest in the subject has beengrowing steadily; efforts have been orchestrated to unravel

its various merits making it indispensable for medical practice

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and decision making. This innovative prospect was fostered bythe writings of Professor Cochrane, a renowned Scottish epide-miologist. At the McMaster University, a research team led by

David Sackett and Gordon Guyatt improvised tactics to verify‘‘best evidence’’. It was only in 1990 that the term ‘‘evidencebased’’ was first used by David Eddy (2). Two years later,the term ‘‘evidence-based medicine (EBM)’’ showed its first

appearance in the medical literature (3). Ever since, a growingnumber of international publications have been released in thedomain of EBM around the globe.

Undoubtedly, the ultimate intention of EBM is to provide atheoretical background on which evidence-based practice(EBP) is founded. However, does reliance on EBM dictums al-

ways leads to an equally satisfying EBP? Are they two sides ofthe very same coin? Are EBM-drawn conclusions too hard-and-fast to defy any argument, reasoning, challenge or ques-

tioning? Such idealism is still, unfortunately, out of reach. Itis prudent to ask ourselves one important question: Is evi-dence-based medicine really evidence-based? If so, how couldwe explain the discrepancies and inconsistencies existent

From evidence-based medicine to evidence-based practice: Is there enough evidence? 295

between EBM and EBP? How did such discrepancies arise?That mentioned, EBM is not a panacea; limits to EBM areboth theoretical and practical. Theoretical limits pivot around

one important fact. EBM provides answers about the likeli-hood if a certain drug, procedure or intervention would havea positive or negative impact on a certain outcome, missing

both the mechanism ‘‘how’’ and cause ‘‘why’’. Consequently,EBM can only be applied to specific dogmas in clinical prac-tice. EBM can help prove that a particular maneuver is bene-

ficial, but it is not so helpful in finding out how or why. As forthe practical limits relevant to EBM, they include insufficientevidence for a myriad of clinical challenges, inadequate exper-tise and talents to make proper and the utmost use of EBM

conclusions and lack of support structures necessary forEBM-centered decision making. Albeit largely considered the‘‘gold standard’’ for sound clinical practice, EBM is weakened

by many criticisms and limitations much detracting from itsvalue. From the ethical point of view, carrying out RCTscan commonly be considered unethical; observational studies

can be the best available means of providing some evidence.Moreover, large multi-center RCTs are so costly, that fundingbodies may play a confounding role in the investigations done

and thereby conclusions drawn. This is best exemplified bystudies funded by pharmaceutical companies trying to verifysafety or efficacy of a certain drug. Furthermore, are EBM-centered guidelines universally applicable to different popula-

tions, timeframes or social circumstances? Is it rational toextrapolate the results of several top-quality studies to all wo-men? Are the conclusions earnestly ‘‘generalizable’’ to other

populations? Moreover, secondary endpoints may be over-looked when interpreting some test results without havingthe power to show a significant change in the general popula-

tion. Studies vary considerably in quality, making it exceed-ingly difficult to compare them and generalize about theresults. In many research trials certain population groups have

been underprivileged and ignored which precludes generaliza-tion of study conclusions (4). Unfortunately, not all evidenceis made accessible; thereby limiting the effectiveness of a givenapproach. The urgent need for reduction of publication bias

and retrieval bias cannot be overemphasized. One of the salientgaps in EBM is its failure to publish negative trials. This can beovercome by registering all trials at the outset, eventually

releasing the awaited results. Mandatory are changes in publi-cation methods, particularly related to the web, to help reducethe difficulty of publishing a paper on a trial that did not prove

anything new, given its initial hypothesis. Moreover, it hasbeen witnessed that the effectiveness of a certain therapy inroutine clinical practice is less than that reported from clinicaltrials, partly due to closer patient monitoring that leads to

higher compliance rates (4). Studies that are published in

medical journals may not be representative of all the publishedand unpublished studies executed on a given topic or may bemisleading due to conflicts of interest (i.e. publication bias)

(4). Consequently, the evidence available on a particular ther-apy may not be truly or completely presented in the literature.Clinicians are still encouraged to make maximal use of their

personal experience treating their patients; EBM basically ap-plies to a sample population. The knowledge gained from clin-ical research does not directly answer the primary clinical

question of what is best for the patient at hand; EBM shouldnot discount the value of clinical acumen (4,5). The practice ofEBM means integrating individual clinical judgment with thebest available external clinical evidence from systematic re-

search (4–7).Conclusively, EBM helps provide evidence, but not all

evidence. Such evidence is not all the time irrefutably accepted

as the only proof. What all clinicians really need is a goodcompromise between the available evidence drawn fromtop-quality research works and that emanating from life-long

experience, sound clinical judgment and personal inferences.The relative weight of each component is left to the vigilantphysician to decide. There remain, however, gaping holes in

evidence on many common clinical topics and among high-riskpopulations. Such currently available gaps mandate properand timely management strategies. The evidence so far is farfrom being inclusive or complete.

The mind of the discerning clinician is always at workdeciding what to do and what not to do, managing each andevery case on its own merits. Decision making can’t be solely

founded on available evidence. With more evidence accumu-lating, decision making is rendered easier.

References

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(4) Sackett DL, Rosenberg WM, Gray JA, Haynes RB and Richard-

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BMJ 1996;312:71–2.

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