This document provides an overview of evidence-based medicine (EBM), including its background, key principles, and methods. It discusses how EBM aims to optimize clinical decision-making by emphasizing the use of evidence from well-designed research studies. Some of the main points covered include formulating answerable clinical questions using the PICO framework, systematically identifying and appraising relevant evidence, understanding different types of research studies and levels of evidence, and incorporating patients' values and preferences into clinical decision-making. The goal of EBM is to improve patient outcomes by ensuring treatment choices are informed by the best available research evidence.
a brief overview about how and why to practice evidence based medicine, its clinical application, what it is and what it is not? benefits and challenges
EBM Is the ability to access, asses and apply the best evidence from systematic research information to daily clinical problems after integrating them with the physician's experience and patient's value.
a brief overview about how and why to practice evidence based medicine, its clinical application, what it is and what it is not? benefits and challenges
EBM Is the ability to access, asses and apply the best evidence from systematic research information to daily clinical problems after integrating them with the physician's experience and patient's value.
Clinical Questions types .
A Hierarchy of Preprocessed Evidence.
EBM definition and value.
Knowledge and Skills Necessary for Optimal Evidence-Based Practice.
Basic computer and internet knowledge for electronic searching of the literature
"Hierarchies of Evidence" is an important but problematic concept for medical professionals to understand as it underpins their capacity to be effective practitioners and researchers.
Principles of evidence based medicine.
EBM means integrating individual clinical expertise with the best available external evidence from systematic research.
This topic is very essential for Pharm.D students. It includes application, benefits, limitations of EBM. It also includes EBM history and background which helps you for examinations. EBM is very important topic in Pharmacotherapeutics-III so you may find this needful.
All the best!!!
Clinical Questions types .
A Hierarchy of Preprocessed Evidence.
EBM definition and value.
Knowledge and Skills Necessary for Optimal Evidence-Based Practice.
Basic computer and internet knowledge for electronic searching of the literature
"Hierarchies of Evidence" is an important but problematic concept for medical professionals to understand as it underpins their capacity to be effective practitioners and researchers.
Principles of evidence based medicine.
EBM means integrating individual clinical expertise with the best available external evidence from systematic research.
This topic is very essential for Pharm.D students. It includes application, benefits, limitations of EBM. It also includes EBM history and background which helps you for examinations. EBM is very important topic in Pharmacotherapeutics-III so you may find this needful.
All the best!!!
Evidence based nursing practice is one of most important for perfect and accurate in terms of saving a life.this presentation covers almost all aspect of EBD
Evidence-Based Medicine - Overview
- How to be a good doctor - A step in Health promotion
- By Ibrahim A. Abdelhaleem - Zagazig Medical Research Society (ZMRS)
EBPStudent’s NameInstitution AffiliationEvidence based pra.docxbudabrooks46239
EBP
Student’s Name
Institution Affiliation
Evidence based practice (EBP)
Clinical Issue
There are multiple of the mental illness which are common such Generalized Anxiety Disorder, Bipolar, Dementia, Schizophrenia and list continues.
There are various models of the treatment such Cognitive behavioral therapy, exposure therapy and medication such as use of antidepressants.
Globally, mental illnesses account for 33% of the disability that adult get due to health problems.
Therefore, narrowing down to Generalized anxiety disorder, my concern is to establish effectiveness of the psychotherapy method of treatment used and specifically cognitive behavioral therapy.
Mental disorder has been global problem that which affects over 900 million people in the world.
Global burden cuts across high income countries to low income countries.
Correct method of treatment of mental illness is important and can be helpful to persons.
Treatment of the mental disorders is put into two categories which are; psychotherapy- behavioral therapy, cognitive therapy, interpersonal therapy, Psychodynamic therapy, Group therapy and Family therapy.
Second category is medication-Antidepressants, Antipsychotics, Mood stabilisers and Sleeping pills and minor tranquillisers.
Choice of the method of treatment is determined by its effictiveness.
2
Development of PICOT
Picot is method of developing of clinical question which was introduced in 1995 (Davies, 2011).
In was developed to help in carrying out the research where relevant information ought to be collected depending on the components of the clinical question that was formulated.
In view of this, PICOT has been basis of formulation of the clinical questions that guides in coming up with evidence based practice which is used in making in making clinical decisions.
Clinicians deal with human life and it is critically important they make decision on the medication that they should give based on the level of the evidence that is available which influence delivery of quality healthcare.
In conducting the research in clinical setting, clinical questions must be formulated.
To ensure that relevant data is corrected, clinical questions is collected using the format of the question known as PICOT.
PICOT has been used since 1995 and has confirmed as an effective way to formulate clinical questions that help to collect data that is analyzed, tested and later inform desion making for better delivery of the quality care.
3
Cont.…
Considering the clinical issue discussed in the second slide, Picot clinical question will be, for generalized anxiety disorder patient, how does cognitive behavioral therapy against antidepressants affects anxiety level within first 8 weeks?
In breaking down the picot question to individual components, P ( patient population): generalized anxiety disorder patient.
I(intervention): cognitive behavioral therapy.
C(comparison): antidepressants
O (Outcome): affects anxiety level
T (time): first.
EVIDENCE –BASED PRACTICES 1
Evidence-Based Practices
Stephanie Petit-homme
Miami Regional University
Professor: Garcia Mercedes
07/05/2021
Evidence-Based Practices to Guide Clinical Practices
In other terms recognized as evidence-based medication, evidence-based scientific practice is elucidated as the careful, obvious, and judicious use of the best indication in creating results for the outstanding care of separate patients. It helps those who brand the choices to device best healthcare practices while drawing the roadmaps for the health system. In clinical trials, the integration of the EBCP entails clinical respiratory medicine considers two fundamental principles. For example, the principle is the hierarchy of the evidence and the art of clinical decision-making.
The interrelationship between the theory, research, and EBP
The relationship between the theory, research, and the EBP supports the three recognition programs. They still relate in terms of the magnet model component of modern knowledge, innovation, and advancement. They describe in a way in which they lead to the promotion of quality in a setting that makes supports professional practices. Second, there is the identification of excellence in giving nursing services to sick people or the people who stay around. For instance, the model, which is other terms the magnet theory, has got five components ( Reddy, 2018).
The first constituent includes transformational management; the additional is structural authorization. The third one is archetypal specialized practices, new information, invention, and upgrading. Lastly, in the model, there are the empirical quality outcomes. For the achievement of the aims of the goals that have been set, there is a need to make sure that the theory, current knowledge innovation, and the improvements and the components that are found in view all the nurses who are located in the levels of the healthcare company need to get involved.
The research has its primary purpose for the help of coming up with knowledge or the validation done for the knowledge that has always been there from before based on the theory. There is systematic, scientific questioning in the research to give the answers to some of the specific questions. It can use the test hypotheses and the rigorous method, the primary purpose of the study being for investigation knowing of the new things and the exploration. There is a need to understand the philosophy of science.
Second, on the EBP, there is no development of the new knowledge or even the learning being validated. The primary purpose of the EBP is to translate the evidence and then apply it to medical executive. It uses the indication available to brand patient-care choices. The EBP goes yonder the exploration as fine as the persevering penchants and ideals. The EBP retains into deliberation that the best indication is for the opinion leaders and the experts. Even though there is the existence of definitiv ...
Operation “Blue Star” is the only event in the history of Independent India where the state went into war with its own people. Even after about 40 years it is not clear if it was culmination of states anger over people of the region, a political game of power or start of dictatorial chapter in the democratic setup.
The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
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The empire's roots lie in the city of Rome, founded, according to legend, by Romulus in 753 BCE. Over centuries, Rome evolved from a small settlement to a formidable republic, characterized by a complex political system with elected officials and checks on power. However, internal strife, class conflicts, and military ambitions paved the way for the end of the Republic. Julius Caesar’s dictatorship and subsequent assassination in 44 BCE created a power vacuum, leading to a civil war. Octavian, later Augustus, emerged victorious, heralding the Roman Empire’s birth.
Under Augustus, the empire experienced the Pax Romana, a 200-year period of relative peace and stability. Augustus reformed the military, established efficient administrative systems, and initiated grand construction projects. The empire's borders expanded, encompassing territories from Britain to Egypt and from Spain to the Euphrates. Roman legions, renowned for their discipline and engineering prowess, secured and maintained these vast territories, building roads, fortifications, and cities that facilitated control and integration.
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Roman architecture and engineering achievements were monumental. They perfected the arch, vault, and dome, constructing enduring structures like the Colosseum, Pantheon, and aqueducts. These engineering marvels not only showcased Roman ingenuity but also served practical purposes, from public entertainment to water supply.
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1. 1
Presented by
Marc Imhotep Cray, M.D.
Companion Article:
Masic I, Miokovic M, Muhamedagic B. Evidence
Based Medicine-New Approaches and Challenges.
Acta Informatica Medica. 2008;16(4):219-225.
2. Marc Imhotep Cray, M.D.
Learning Objectives
2
By the end of this presentation the learner should:
Understand the background, history, definition and
importance of evidence-based medicine.
Know how to formulate clinically relevant,
answerable questions using the Patient
Intervention Comparison Outcome (PICO)
framework.
Be able to systematically perform a literature
search to identify relevant evidence.
Understand the importance of assessing the
quality and validity of evidence by critically
appraising the literature.
Know that different study designs provide varying
types and levels of evidence.
3. Marc Imhotep Cray, M.D.
Scope of Evidence-Based Medicine
3
Term "evidence-based medicine" has
two main tributaries
First is insistence on explicit evaluation of
evidence of effectiveness when issuing
clinical practice guidelines and other
population-level policies
Second is introduction of epidemiological
methods into medical education and
individual patient-level decision-making
o This tributary had its foundations in clinical
epidemiology a discipline that teaches medical
students and physicians how to apply clinical and
epidemiological research studies to their practices
4. Graphic from: Guyatt G et al. (Eds). Users’ Guides to the Medical Literature: Essentials of Evidence-Based Clinical Practice 3rd Ed. New York: McGraw-Hill Education-JAMA Network, 2015.
Background, history and definition
EBM methods were published to a broad
physician audience in a series of 25 "Users’
Guides to the Medical Literature" published in
JAMA between 1993 and 2000 by the
Evidence-based Medicine Working Group at
McMaster University.
6. Marc Imhotep Cray, M.D.
What is EBM? (2)
6
Sackett and colleagues describe evidence-based
medicine (a.k.a. evidence-based practice[EBP])
as “the conscientious, explicit and judicious use
of current best evidence in making decisions
about the care of individual patients”
Sackett DL, et al. BMJ. 1996; (7023): 71-72.
7. Marc Imhotep Cray, M.D.
What is EBM? (3)
7
“Evidence-based medicine (EBM) is the process
of systematically reviewing, appraising and using
clinical research findings to aid the delivery of
optimum clinical care to patients”
Rosenberg W, Donald A. Evidence based medicine: an approach to clinical
problem-solving. BMJ 1995; 310: 1122–1126.
8. Marc Imhotep Cray, M.D.
What is EBM ? (4) Capsule
8
EBM is an approach to medical practice
intended to optimize decision-making by
emphasizing use of evidence from well-
designed and well-conducted research
Although all medicine based on science has some
degree of empirical support EBM goes further
classifying evidence by its scientific strength and
requiring that only strongest types evidence (i.e.,
meta-analyses, systematic reviews, randomized
controlled trials) can yield strong recommendations
o weaker types of evidence (such as from case-control
studies) can yield only weak recommendations
9. Marc Imhotep Cray, M.D.
History of EBM
9
1940s-Formal assessment of medical interventions
using controlled trials well established
1972-Prof. Archie Cochrane, director of Medical
Research Council Epidemiology Research Unit in
Cardiff expressed what later came to be known as
evidence-based medicine (EBM) in his book
Effectiveness and Efficiency: Random Reflections on
Health Services
Late 1980s and early 1990s-EBM concepts were
developed into a practical methodology by groups at
Duke University in North Carolina (David Eddy) and
McMaster University in Toronto (Gordon Guyatt and
David Sackett)
10. Marc Imhotep Cray, M.D.
History of EBM (2)
10
1992- UK government funded establishment of
Cochrane Centre in Oxford objective was to facilitate
preparation of systematic reviews of randomized
controlled trials of healthcare
1993-Cochrane Centre expanded into an international
collaboration of centres, of which (as of 2009) there
were thirteen, whose role is to co-ordinate activities of
11,500 researchers
NB: Cochrane Collaboration considered as one of critical
factors in spreading concept of EBM worldwide
11. Marc Imhotep Cray, M.D.
Main elements of EBM
11
EBM is part of multifaceted process of assuring
clinical effectiveness main elements are:
Production of evidence through research and
scientific review
Production and dissemination of evidence-based
clinical guidelines
Implementation of evidence-based, cost effective
practice through education and management of
change
Evaluation of compliance with agreed practice
guidance through clinical audit and outcomes-
focused incentives
12. Marc Imhotep Cray, M.D.
Key principles of EBM
12
EBM involves a number of key principles
discussed in turn during course of presentation:
Formulate a clinically relevant question
Identify relevant evidence
Systematically review and appraise evidence
identified
Extract most useful results and determine whether
they are important in your clinical practice
Synthesize evidence to draw conclusions
Use clinical research findings to generate guideline
recommendations which enable clinicians to deliver
optimal clinical care to patients
Evaluate implementation of EBM
13. Marc Imhotep Cray, M.D.
Core of Evidence-Based Medicine
13
At core of EBM is a care and respect for patients who
will suffer if clinicians fall prey to muddled clinical
reasoning and to neglect or misunderstanding of
research findings
Practitioners of EBM strive for a clear & comprehensive
understanding of evidence underlying their clinical
care and work w each pt. to ensure that chosen
courses of action are in that pt’s best interest
Practicing EBM requires clinicians to understand how
uncertainty about clinical research evidence intersects
w an individual pt’s predicament, values & preferences
14. Marc Imhotep Cray, M.D.
Logic behind EBM
14
To make EBM more acceptable to clinicians
and to encourage its use best to turn a
specified problem into answerable questions
by examining:
Person or population in question
Intervention given
Comparison (if appropriate)
Outcomes considered
Next, it is necessary to refine problem into
explicit questions then check to see
whether evidence exists
But where can we find information to help us
make better decisions?
15. Marc Imhotep Cray, M.D.
What is involved in identification, appraisal and
application of evidence summarized in reviews?
15
Framing questions
↓
Identifying relevant reviews
↓
Assessing quality of review and
its evidence
↓
Summarizing the evidence
↓
Interpreting finding
17. Marc Imhotep Cray, M.D.
Where can we find information?
17
Common sources include:
Personal experience for example, a bad drug
reaction
Reasoning and intuition
Colleagues
Published evidence
o meta-analyses, systematic reviews and
randomized controlled trials
NB: By becoming educated in strength of published
evidence (and critical appraisal ), in contrast to more
traditional--less rigorous--sources of information use of
ineffective, costly or potentially hazardous interventions
can be reduced
18. Marc Imhotep Cray, M.D.
Formulating Clinical Questions
18
In order to practice evidence-based
medicine initial step = converting a clinical
encounter into a clinical question
A useful approach to formatting a clinical (or
research) question Patient Intervention
Comparison Outcome (PICO) framework
19. Marc Imhotep Cray, M.D.
Formulating Clinical Questions (2)
Patient Intervention Comparison Outcome (PICO)
framework
19
Question is divided into four key components:
1. Patient/Population: Which pts. or popul. group of
pts. are you interested in?
Is it necessary to consider any subgroups?
2. Intervention: Which intervention/treatment is being
evaluated?
3. Comparison/Control: What is/are main alternative/s
compared to intervention?
4. Outcome: What is most important outcome for
patient?
Outcomes can include short- or long-term measures,
intervention complications, social functioning or quality of
life, morbidity, mortality or costs
20. Marc Imhotep Cray, M.D.
PICO Framework illustrated
20
Patient Children with congestive heart failure
Intervention Carvedilol (a β-blockers )
Comparison No carvedilol
Outcome Improvement of CHF symptoms
Clinical Encounter
Ali, 30 years old, was diagnosed with heart failure at 4
years old and prescribed a beta-blocker which
dramatically improved his symptoms. Ali’s 5- year-old
daughter, Leda, has been recently diagnosed with
chronic symptomatic CHF. Ali asks you, whether his
daughter should also be prescribed a beta-blocker.
Question: Is there a role for beta-blockers in the
management of heart failure in children?
21. Marc Imhotep Cray, M.D.
Formulating Clinical Questions (4)
Types of research questions (=Tx/ Etio/ Dx/ Px)
21
Not all research questions ask whether an intervention
is better than existing interventions or no Tx at all
From a clinical perspective EBM is relevant for three
other key domains:
1. Etiology: Is exposure a risk factor for developing a certain
condition?
2. Diagnosis: How good is diagnostic test (history taking,
physical examination, laboratory or pathological tests and
imaging) in determining if a pt. has a particular condition?
Questions usually asked about clinical value or diagnostic
accuracy of test
3. Prognosis: Are there factors related to pt. that predict a
particular outcome (disease progression, survival time after
Dx of disease, etc.)?
Px is based on characteristics of pt. (“prognostic factors”)
22. Marc Imhotep Cray, M.D.
Formulating Clinical Questions (5)
22
Important that pt. experience is taken into
account when formulating clinical question
(p)atient experience may vary depending on which
pt. population is being addressed
Following pt. views should be determined:
o Acceptability of proposed (i)ntervention being evaluated
o Preferences for Tx options already available (c)
o What constitutes an appropriate, desired or acceptable
(o)utcome
NB: Incorporating above pt. views will ensure clinical
question is patient-centered and therefore clinically
relevant
23. Marc Imhotep Cray, M.D.
Identifying Relevant Evidence
23
Three Ways to Use the Medical Literature
Staying Alert to Important New Evidence
Problem Solving
Asking Background & Foreground Questions
Analyzing information
In using evidence it is necessary to:
o Search for and locate it
o Appraise it
o Interpret it in context
o Implement it
o Store and retrieve it
o Ensure it is updated
o Communicate it
24. Marc Imhotep Cray, M.D.
Ways to Use Medical Literature
24
Medical student, in early training, seeing a
patient with newly diagnosed type 2 diabetes
mellitus She will ask questions such as:
What is type 2 diabetes mellitus?
Why does this patient have polyuria?
Why does this pt. have numbness & pain in his legs?
What treatment options are available?
These questions address normal physiology and
pathophysiology assoc. w a medical condition
Traditional medical textbooks that describe
underlying pathophysiology or epidemiology of a
disorder provide an excellent resource for addressing
these background questions
25. Marc Imhotep Cray, M.D.
Ways to Use Medical Literature (2)
25
…In contrast, sorts of foreground questions
that experienced clinicians usually ask
require different resources, namely using
current medical literature for pt.-related
problem solving
Formulating a question is first step and
critical skill for this evidence-based
practice (EBP)
Ways to use medical literature that follow
provide an opportunity to start learning &
practicing the skill
26. Marc Imhotep Cray, M.D.
Ways to Use Medical Literature (3)
26
“Clinicians do Problem Solving”
Experienced clinicians managing a pt. w T2DM
will ask questions such as:
In pts w new onset T2DM, which clinical features or
test results predict development of diabetic
complications?
In pts with T2DM requiring drug therapy, does
starting w metformin Tx yield improved diabetes
control and reduce long-term complications better
than other initial treatments?
NB: Here, clinicians are defining specific questions
raised in caring for pts then consulting the
medical literature to resolve these questions
27. Marc Imhotep Cray, M.D.
Ways to Use Medical Literature (3)
27
Most valuable single free access point is The
Cochrane Library
The Cochrane Library contains high-quality,
independent evidence to inform all healthcare
decision-making
An alternative to alerting systems are
secondary evidence based journals
For example, in internal and general medicine, ACP
Journal Club (http://acpjc.acponline.org) publishes
synopses of articles that meet criteria of both high
clinical relevance and methodologic quality
See: Haynes RB, Cotoi C, Holland J, et al; McMaster Premium Literature
Service (PLUS) Project. Second-order peer review of the medical literature
for clinical practitioners. JAMA. 2006;295(15):1801-1808
28. Marc Imhotep Cray, M.D.
Ways to Use Medical Literature (4)
28
Most efficient strategy for ensuring you are
aware of recent developments relevant to your
practice is to subscribe to e-mail alerting
systems, such as EvidenceAlerts
A free service w research staff screening approx.
45, 000 articles per year in more than 125 clinical
journals for methodologic quality and a worldwide
panel of practicing physicians rating them for
clinical relevance and newsworthiness
29. 29
Asking Background & Foreground Questions
One can think of first set of
questions, those of medical
student, as background
questions and of browsing and
problem-solving sets as
foreground questions
In most situations you
need to understand
background thoroughly
before it makes sense to
address foreground issues
Guyatt G et al. (Eds). Users’ Guides to the Medical Literature:
Essentials of Evidence-Based Clinical Practice 3rd Ed. New York:
McGraw-Hill Education-JAMA Network, 2015.
30. Marc Imhotep Cray, M.D. 30
Five Types of Foreground Clinical Questions
In addition to clarifying population,
intervention or exposure, and outcome, it
is productive to label nature of question
that you are asking
Finding a Suitably Designed Study for Your
Question Type
You need to correctly identify category of
study b/c to answer your question, you
must find an appropriately designed
study
o For example, if you look for a randomized
trial to inform properties of a diagnostic test,
you will not find answer you seek
31. Marc Imhotep Cray, M.D.
There are 5 fundamental types of
clinical questions
31
1. Therapy: determining effect of interventions on patient
important outcomes (symptoms, function, morbidity,
mortality, and costs)
2. Harm: ascertaining effects of potentially harmful agents
(including therapies from first type of question) on
patient-important outcomes
3. Differential diagnosis: in patients with a particular
clinical presentation, establishing the frequency of the
underlying disorders
4. Diagnosis: establishing power of a test to differentiate
Betw. those with and without a target condition or disease
5. Prognosis: estimating a patient’s future course
We will now review study designs associated with 5
major types of questions.
32. Marc Imhotep Cray, M.D. 32
Structure of Randomized Trials
To answer questions about a therapeutic issue, we seek a
randomized trial (group assignment analogous to flipping a coin)
Once investigators allocate participants to treatment or control
groups they follow them forward in time to determine whether
they have, for instance, a stroke or myocardial infarction what
we call outcome of interest
Guyatt G et al. (Eds). Users’ Guides to the Medical Literature: Essentials of Evidence-Based Clinical Practice
3rd Ed. New York: McGraw-Hill Education-JAMA Network, 2015.
33. 33
Structure of Observational Cohort Studies
Ideally, we would also look to randomized trials to address issues of harm
For most potentially harmful exposures, however, randomly allocating patients is
neither practical nor ethical
o For example , one cannot suggest to potential study participants that an
investigator will decide by the flip of a coin whether or not they smoke during
next 20 years
For exposures such as smoking, best one can do is identify observational
studies (subclassified as cohort or case-control studies) provide less
trustworthy evidence than randomized trials
Guyatt G et al. (Eds). Users’ Guides to the Medical Literature: Essentials of Evidence-Based Clinical Practice
3rd Ed. New York: McGraw-Hill Education-JAMA Network, 2015.
34. Marc Imhotep Cray, M.D.
Structure of Studies of Differential
Diagnosis
34
For sorting out differential diagnosis investigators collect a
group of patients with a similar presentation (eg, painless jaundice,
syncope, or headache), conduct an extensive battery of tests,
and if necessary follow patients forward in time
Ultimately, for each pt. investigators hope to establish underlying
cause of symptoms and signs with which pt. presented
Guyatt G et al. (Eds). Users’ Guides to the Medical Literature: Essentials of Evidence-Based Clinical Practice
3rd Ed. New York: McGraw-Hill Education-JAMA Network, 2015.
35. Marc Imhotep Cray, M.D.
Structure of Studies of Diagnostic
Test Properties
35
In diagnostic test studies, investigators identify a group of patients
among whom they suspect a disease or condition of interest exists
(such as tuberculosis, lung cancer, or iron deficiency anemia)
which we call the target condition
Pts. undergo new diagnostic test and a reference standard (also
referred to as gold standard or criterion standard)
Investigators evaluate diagnostic test by comparing its classification
of pts. w that of reference standard
Guyatt G et al. (Eds). Users’ Guides to the Medical Literature: Essentials of Evidence-Based Clinical Practice
3rd Ed. New York: McGraw-Hill Education-JAMA Network, 2015.
36. 36
Structure of Studies of Prognosis
Final type of study examines a patient’s prognosis and may identify factors
that modify that prognosis
Here, investigators identify pts who belong to a particular group (such as
pregnant women, pts. undergoing surgery, or pts w cancer) with or without
factors that may modify their prognosis (such as age or comorbidity)
The exposure here is time investigators follow up pts to determine if they
experience the target outcome such as an adverse obstetric or neonatal event
at end of a pregnancy, a myocardial infarction after surgery, or survival in cancer
Guyatt G et al. (Eds). Users’ Guides to the Medical Literature: Essentials of Evidence-Based Clinical Practice
3rd Ed. New York: McGraw-Hill Education-JAMA Network, 2015.
38. Marc Imhotep Cray, M.D.
Finding Current Best Evidence
38
Searching for Evidence is a Clinical Skill
Searching for current best evidence in
medical literature has become a central skill
in clinical practice
On average, clinicians have 5 to 8 questions
about individual patients per daily shift and
regularly use online evidence-based medicine
(EBM) resources to answer them
See: Chapter 4, Finding Current Best Evidence. In: Guyatt G et al.
(Eds). Users’ Guides to the Medical Literature: Essentials of
Evidence-Based Clinical Practice 3rd Ed. New York: McGraw-Hill-
JAMA Network, 2015.
39. Marc Imhotep Cray, M.D.
Categories of EBM Resources
39
Summaries and guidelines
UpToDate
DynaMed
Clinical Evidence
Best Practice
US National Guidelines
Clearinghouse
Preappraised research
ACP Journal Club
McMaster PLUS
DARE
Cochrane
Evidence Updates
Nonpreappraised research
PubMed (MEDLINE)
CINAHL
CENTRAL
Filters:
Clinical Queries in PubMed
Federated searches (engines)
ACCESSSS
Trip
SumSearch
Epistimonikos
Abbreviations: ACCESSSS, ACCess to Evidence-based Summaries, Synopses,
Systematic Reviews and Studies; CENTRAL, Cochrane Central Register of Controlled
Trials; CINAHL, Cumulative Index to Nursing and Allied Health Literature; DARE,
Database of Abstracts of Reviews of Effects.
40. Marc Imhotep Cray, M.D. 40
http://www.cochranelibrary.com/
Free EBM alerting system
41. Marc Imhotep Cray, M.D.
Databases included in The Cochrane Library
41
Belsey J. What is evidence-based medicine? Hayward Medical Communications, 2009.
42. Marc Imhotep Cray, M.D. 42
https://plus.mcmaster.ca/EvidenceAlerts/
Free EBM alerting system
43. Marc Imhotep Cray, M.D. 43
https://www.nlm.nih.gov/bsd/pmresources.html
Free Medical Literature Research Portal
44. Marc Imhotep Cray, M.D. 44
http://www.medscape.com/
http://jama.jamanetwork.com/journal.aspx
Peer-Reviewed Publications, News, Alerts and CME
45. Marc Imhotep Cray, M.D.
Critically Appraising the Evidence
45
Once all possible studies have been identified
w literature search each study needs to be
assessed for eligibility against objective criteria
for inclusion or exclusion
Having identified those studies that meet
inclusion criteria they are subsequently
assessed for methodological quality using a
critical appraisal framework
Despite satisfying inclusion criteria, studies
appraised as being poor in quality should also be
excluded
46. Marc Imhotep Cray, M.D.
Critical appraisal (2)
46
Critical appraisal is process of systematically
examining available evidence to judge its
validity, and relevance in a particular context
Appraiser should make an objective
assessment of study quality and potential for
bias
Note: Methodological checklists for critically appraising
study designs will be covered in a subsequent lecture
47. Marc Imhotep Cray, M.D.
Critical appraisal (3)
47
Important to determine both internal validity
and external validity of study:
External validity: extent to which study findings are
generalizable beyond limits of study to study’s
target population.
Internal validity: Ensuring that study was run
carefully (research design, how variables were
measured, etc.) and extent to which observed
effect(s) were produced solely by intervention being
assessed (and not by another factor)
Three main threats to internal validity (confounding,
bias and causality) for each of the key study designs are
discussed in subsequent lectures
48. Marc Imhotep Cray, M.D.
Evaluating the Literature: Capsule
48
Theodore J Gaeta et al. Evaluating the Literature.
Accessed 07-08-17
Available at http://emedicine.medscape.com/article/773527
…reviewing medical literature poses a challenge to busy
physicians. A willingness and ability to do so enhance
quality of practice they bring to each of their patients.
To save time, a brief primary survey of article of interest
informs reader as to potential value of findings and to
whether a more in-depth review is indicated. If so, this
detailed analysis (secondary survey) allows reader to
determine whether article's conclusion is supported by its
results and whether these results are believable.
Knowledge of standard anatomy of an article and
idiosyncrasies of various types of studies will assist reader
to intelligently review medical literature efficiently…
49. Marc Imhotep Cray, M.D.
Conclusion: Using the Medical Literature
Provides for Optimal Patient Care.
49
Guyatt G et al. (Eds). Users’ Guides to the Medical Literature: Essentials of Evidence-
Based Clinical Practice 3rd Ed. New York: McGraw-Hill Education-JAMA Network, 2015.
50. 50See next slide for links to tools and resources for further study.
51. Marc Imhotep Cray, M.D.
Sources and further study:
51
Textbooks
Kaura A. Evidence-Based Medicine: Reading and Writing Medical
Papers (Crash Course Series). Philadelphia: Mosby- Elsevier,
2012.
Guyatt G et al. (Eds). Users’ Guides to the Medical Literature:
Essentials of Evidence-Based Clinical Practice 3rd Ed. New York:
McGraw-Hill Education-JAMA Network, 2015.
Swiger KJ et al. (Eds). 50 studies every internist should know.
New York: Oxford University Press, 2015.
Cloud Folders
EBM (Evidence Based Medicine), Reading the Medical Literature
and Medical Writing
52. Marc Imhotep Cray, M.D.
External Links
52
Lefebvre, C., Manheimer, E., Glanville, J., 2011. Searching for studies. In:
Higgins, J.P.T., Green, S. (Eds.), Cochrane Handbook for Systematic Reviews of
Interventions. Version 5.1.0 (updated March 2011). The Cochrane
Collaboration. National Institute for Health and Clinical Excellence, March
2012. The Guidelines Manual. National Institute for Health and Clinical
Excellence, London. Available from: http:// www.nice.org.uk
Sackett, D.L., Rosenberg, W.M.C., 1995. The need for evidence based
medicine. J. R. Soc. Med. 88, 620–624.
Sackett, D.L., Rosenberg, W.M.C., Gray, J.A.M., Haynes, R.B., Richardson, W.S.,
1996. Evidence based medicine: What it is and what it isn’t. BMJ 312, 71–72.
Straus, S.E., McAlister, F.A., 2000. Evidence-based medicine: A commentary on
common criticisms. CMAJ 163, 837–841.