This document discusses evidence-based medicine (EBM) and its importance in helping clinicians navigate the vast amount of medical information available. It defines EBM as integrating the best research evidence with clinical expertise and patient values. The document outlines the stages of EBM, from identifying a clinical problem to implementing evidence in patient care. It also discusses resources for finding evidence, barriers to EBM, and the benefits it provides like improving patient outcomes and reducing unnecessary treatment.

1. International Educational Applied Scientific Research Journal
ISSN (Online): 2456-5040
Volume: 1 | Issue: 1 | October 2016
40
THE MERITS OF EVIDENCE BASED MEDICINE IN MEDICAL
INFORMATION JUNGLE
PAVANI PRIYADARSINI
Freelance Medical Writer, Hyderabad, India-500004.
ABSTRACT
Most clinicians neither have enough time nor are trained to pick the best information from the enormous literature available. By
practicing Evidence Based Medicine, they can give better patient care. EBM is the integration of the best research evidence with
clinical expertise and patient values to make clinical decisions.
Key Words: Evidence Based Medicine, Evidence Based Practice, Patient care.
INTRODUCTION:
The first randomized controlled trial (RCT) was published in
the British Medical Journal in 1948. 1
Now, several databases
containing numerous clinical trials are available. Medical
research grows at a rapid pace. Clinical practitioners do not
have enough time to go through all the new information that
is being published. They are also not trained to pick the best
information from the vast material which is available both
online and offline. Here comes the role of Evidence Based
Medicine (EBM). EBM is the integration of the best research
evidence with clinical expertise and patient values to make
clinical decisions. 2
The classical definition of EBM is credited to David L.Sackett
: conscious, explicit and sensate use of the best evidence
available in decision making about patient care, added to the
physician's experience and the patient's preferences. 3
As the
EBM precepts were incorporated into other disciplines, it
started to be called Evidence-Based Practice (EBP).4
Research studies show that EBP leads to higher quality care,
improved patient out-comes, reduced costs, and greater nurse
satisfaction than traditional approaches to care. 5
Research
literature is not static. It is changing continuously. The best
guidelines this year may be modified next year. The task of
staying current, although never easy, is made much simpler
by incorporating the tools of EBM into everyday practice. 6
HOW CAN CLINICIANS PRACTICE EBM?
For improved patient care, health care professionals can
practice EBM in the following ways: 7
1. Clinicians must recognize the gaps in their own
information retrieval and evaluation skills.
2. They should look for and obtain continuing education
that enhances the relevant skill sets.
3. They should demand greater access to high-quality
information resources in the workplace.
4. Clinicians should demonstrate a commitment to using
information resources effectively to improve care.
5. They should set goals for integrating evidence-based
practice that link practice interventions to patient and
hospital outcomes.
THE STAGES OF EBP: 8
1. Identification of a clinical problem.
2. Formulation of a relevant, specific and answerable
clinical question.
3. Searching and finding the scientific evidence in the
literature and online databases.
4. Critical appraisal tools: Appraising the evidence
gathered with regard to its validity and relevance.
5. Evaluation of clinical applicability of evidence.
6. Implementation of evidence in the patient care. Making
a decision and integrating the evidence with clinical
expertise and patient values.
7. Evaluation of the changing results.
EBM RESOURCES:
Where to begin a search? The tools to find the Evidence in
EBM are called EBM tools. Prominent among them are
MEDLINE, EBM Reviews, Cochrane Library and Clinical
Evidence. The web sites are www.nlm.nih.gov,
www.cochrane.org, www.guideline.gov, www.cinahl.com,
etc.
MEDLINE, PubMed, Index Medicus: MEDLINE is created
by US National Library of Medicine. It is an easy to use
interface. It has both basic and advanced search options. One
can effectively search information using Medical Subject

2. International Educational Applied Scientific Research Journal
ISSN (Online): 2456-5040
Volume: 1 | Issue: 1 | October 2016
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Headings (MeSH). As of July 2016, 5630 journals are
indexed in MEDLINE. MEDLINE includes journals that are
cited as INDEX-MEDICUS as well as other non-INDEX-
MEDICUS journals. Journals are selected on the basis of
recommendations of a selection committee. MEDLINE is
available online and at no cost through PubMed, or it can be
obtained for a fee through several subscription databases like
Ovid. PubMed has been available since 1996. Its more than
25 million references include the MEDLINE database plus
other types of citations. The National Guideline
Clearinghouse, a program of the U.S. Department of Health
and Human Services, is a database of evidence-based clinical
practice guidelines. The web site is www.guideline.gov.
Barriers to EBM :
Too much literature, not enough time. 9
To stay current with
advances in the field, it is estimated that health care
professionals would have to read 19 journal articles per day
every day of the year.10
Research barriers, lack of resources,
lack of time, inadequate skills, and inadequate access, lack of
knowledge and financial barriers were found to be the most
common barriers to EBM .11
EBM GLOSSARY: 12
Following are some of the key terms in relation to Evidence-
Based Medicine.
Absolute risk reduction (ARR): The difference in the event
rate between control group (CER) and treated group (EER):
ARR = CER – EER.
Bias: Any tendency to influence the results of a trial (or their
interpretation) other than the experimental intervention.
Blinding: A technique used in research to eliminate bias by
hiding the intervention from the patient, clinician, and/or
other researchers who are interpreting results.
Clinical practice guideline: A systematically developed
statement designed to assist health care professionals and
patients make decisions about appropriate health care for
specific clinical circumstances.
Cochrane collaboration: A worldwide association of groups
who create and maintain systematic reviews of the literature
for specific topic areas.
Effectiveness: A measure of the benefit resulting from an
intervention for a given health problem under usual
conditions of clinical care for a particular group.
Efficacy: A measure of the benefit resulting from an
intervention for a given health problem under the ideal
conditions of an investigation.
Forrest plot: A diagrammatic representation of the results of
individual trials in a meta-analysis.
Funnel plot: A method of graphing the results of trials in a
meta-analysis to show if the results have been affected by
publication bias.
Negative predictive value (-PV): The proportion of people
with a negative test who are free of disease.
Number needed to treat (NNT): The number of patients
who need to be treated to prevent one bad outcome. It is the
inverse of the ARR: NNT=1/ARR.
Odds: A ratio of events to non-events. If the event rate for a
disease is 0.2 (20%), its non-event rate is 0.8 and therefore its
odds are 2/8.
Positive predictive value (+PV): The proportion of people
with a positive test who have disease.
Publication bias: A bias in a systematic review caused by
incompleteness of the search, such as omitting non-English
language sources, or unpublished trials (inconclusive trials are
less likely to be published than conclusive ones, but are not
necessarily less valid).
Randomized trial: An epidemiological experiment in which
subjects in a population are randomly allocated into groups,
usually called study and control groups, to receive or not
receive an experimental preventive or therapeutic procedure,
maneuver, or intervention. The results are assessed by
rigorous comparison of rates of disease, death, recovery, or
other appropriate outcome in the study and control groups.
Relative risk (RR) (or risk ratio): The ratio of the risk of an
event in the experimental group compared to that of the
control group (RR=EER / CER).
Relative risk reduction (RRR): The percentage reduction in
events in the treated group event rate (EER) compared to the
control group event rate (CER): RRR = (CER-EER) / CER.
Sensitivity: The proportion of people with disease who have
a positive test.
Specificity: The proportion of people free of a disease who
have a negative test.
Systematic review: The application of strategies that limit
bias in the assembly, critical appraisal, and synthesis of all
relevant studies on a specific topic. Systematic reviews focus
on peer-reviewed publications about a specific health problem
and use rigorous, standardized methods for selecting and
assessing articles. A systematic review may or may not
include a meta-analysis, which is a quantitative summary of
the results.
Treatment benefits: Positive patient-relevant outcome
associated with an intervention, quantifiable by
epidemiological measures such as absolute risk reduction
(ARR) and number needed to treat (NNT).

3. International Educational Applied Scientific Research Journal
ISSN (Online): 2456-5040
Volume: 1 | Issue: 1 | October 2016
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Validity: The extent to which a variable or intervention
measures what it is supposed to measure or accomplishes
what it is supposed to accomplish. The internal validity of a
study refers to the integrity of the experimental design. The
external validity of a study refers to the appropriateness by
which its results can be applied to non-study patients or
populations.
BENEFITS OF EBM:
Guidelines improve health outcomes. They discourage
ineffective interventions. This leads to reduced morbidity and
mortality. Guidelines can also improve the consistency of
care; studies around the world show that the frequency with
which procedures are performed varies dramatically among
doctors, specialties, and geographical regions, even after case
mix is controlled for .13
The patients will be cared for in
similar manner in all locations and by all clinicians.
POTENTIAL HARMS:
Some clinical guidelines, especially those developed by
medical and other groups unconcerned about financing, may
advocate costly interventions that are unaffordable or that cut
into resources needed for more effective services.14
Conflicting guidelines from different professional bodies can
also confuse and frustrate practitioners.15
CONCLUSION:
EBM provides short, comprehensible and applicable
guidelines to clinicians to apply latest research findings in
their practice.
Conflict of interest: Nil.
Funding: Nil.
Ethical Permission: Not needed.
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