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Evidence-Based Practice Introduction to methods and searching for Librarians. Ann McKibbon MLS PhD McMaster University [email protected] Have fun Stretch your minds Make clinical decisions Ask questions and make comments Make mistakes and say dumb things Develop some new skills

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Evidence based practice introduction to methods and searching for librarians

Evidence-Based PracticeIntroduction to methods and searching for Librarians

Ann McKibbon MLS PhD

McMaster University

[email protected]

Rules for the day

Have fun

Stretch your minds

Make clinical decisions

Ask questions and make comments

Make mistakes and say dumb things

Develop some new skills

Stop me for breaks

Rules for the day

Morning agenda

Morning Agenda

Introduction to EBM

EBM and the question

EBM and searching/retrieval

Categories of care

How are the similar

How are they different

EBM and the article

Types of articles

What makes a “good’ one



How they differ?

What makes them strong?

How do I find them?





Systematic reviews

Current working pragmatic definition

Current Working (Pragmatic) Definition

…a set of tools, resources, and procedures

…for finding current best evidence from research

…and applying this evidence

…for decision making with respect to

the care of individual patients (EBM, EBN, EBD, EBHC)

the care of groups of people (EBPublic Health)

the running of your library (EBL)

raising your child (EBParenting)

…taking into account the situation, culture, resources, and common sense

Historical roots of ebp

Historical Roots of EBP

Daniel—first clinical trial with Shadrack, Meshack, and Abednigo

The results? At the end of 10 days, they "appeared better and fatter than all the young men who had been eating the royal rations" (v:15), and …the king found them in learning and wisdom to be "ten times better than all the magicians and enchanters in his whole kingdom" (vs:18-19).

Ibn sina 981 1037

Ibn Sina (981-1037)

Rules of drug evaluation

The drug must have a specific defined mode of action

It must be tested on a well defined disease

The time of action must be observed

The effect of the drug must been seen to occur consistently in many cases

The experimentation must be done on the human body (horses or lions may react differently than a human)

Historical roots of ebp1

Historical Roots of EBP


Late 1700s

12 sailors

Dramatic results

Slow implementation

Osler information


It is astonishing with how little reading a doctor can practice medicine, but it is not astonishing how badly he may do it.

Historical roots of ebp2

Historical Roots of EBP

First randomized trial

--not enough drug in UK

--George Orwell not

eligible for trial

Eb health care first version
EB Health Care—First Version


Evidence Clinical Expertise

Eb health care new version
EB Health Care—New Version

Clinical Circumstances

Clinical Experience

Patient preferences Evidence

and actions

5 steps of ebhc
5 Steps of EBHC

  • Framing the question appropriate to the needs of the patient

  • Finding the evidence

  • Evaluating the evidence (critical appraisal)

  • Making and doing the decision

  • Evaluation of the whole process

Critical appraisal
Critical appraisal

Three-step process

  • Find out how good (strong) the evidence is (assessment of the methods)

  • Find out what the results are and how strong they are

  • Figure out how our patient (or patient group) and settings matches with the study patients and setting

Critical appraisal1
Critical appraisal

Go to first page of supplemental package

Pictorial representation of the EB process from a clinical perspective

Most of the steps are done intuitively and not on paper

New awareness of the importance of evidence and difficulties to find accumulate

New Awareness of the Importance of Evidence and Difficulties to Find/Accumulate

Systematic reviews and meta-analyses

Presence of search strategies a measure of quality

Expert searching—have we lost our edge?

Seeing a true collaboration (work as equals)

Searching and data management

Cochrane and Campbell Collaborations, DARE

Librarians full members with own sections on methods

CADTH, AHRQ and Technology Assessment

As above (Jessie McGowan)

Guidelines and Care Maps

Librarians true partners (Ruth Holst)

Professional Societies hire librarians/contract for services


Need for new information tools and techniques

Need for new information tools and techniques to Find/Accumulate

Books and book-like products

Clinical Evidence has much librarian input—searching etc


Summary Journals

ACP Journal Club, EBM, EBN

Web pages and sites

MEDLINEPLUS and Go Local implementations

Provide sites and production

New products

OVID EBM Reviews and other aggregated services

PubMED Clinical Queries


New services

New respect for our abilities collections

New Respect for our Abilities to Find/Accumulate/Collections


Preparation, editing of grants

Teaching of grant writing skills (Wessel & Pitt modules)

Institutional Review Boards


Standards (Kate Oliver)

New service opportunities

Scherrer and publication process

Code Yellow—Library 911


EBM workshops in Hamilton and Denver

Limited only by our


Ability to recognize and create opportunities

Clinical research
Clinical Research to Find/Accumulate

Move now to looking at clinical research…

…the kind of research that is strong enough and applicable enough for use in making/changing clinical decisions

Clinical research1
Clinical Research to Find/Accumulate

  • Question based—once question formed

  • Methods

    • Observation

    • Manipulation/experimental

  • Which is stronger to do?

  • Which is easier to do?

  • Do we need both?

  • Why?

Observational or experimental
Observational or Experimental? to Find/Accumulate

  • What is the process that elderly people go through as they come to terms with living in an assisted living arrangement?

  • Does yoga improve fatigue levels in people recovering from cancer?

  • How effective is this appetite reducing drug in relation to exercise?

  • Do suduku puzzles protect me from developing Alzheimer disease?

  • What is my life expectancy now that you have told me I have ALS?

  • Is this blood test as effective as stomach biopsy at telling me that I have celiac disease?

Publishing wedge therapy
Publishing Wedge (therapy) to Find/Accumulate


Idea development



Early human Phase I

Middle human Phase II

Late human Phase III

Categories of clinical literature

Original studies to Find/Accumulate





Clinical prediction guides

Differential diagnosis

Qualitative studies


Systematic reviews/ meta-analyses

Clinical practice guidelines

Economic studies

Decision analyses

Categories of clinical literature

Similarities across categories
Similarities across categories to Find/Accumulate

Done to answer legitimate and important problems and issues

Meet standards

  • Ethical

  • Moral

  • Record keeping and reporting

  • Publishing standards and procedures

Similarities across categories1
Similarities across categories to Find/Accumulate

  • Question based

  • Preplanned

  • Comparative

  • Patients/participants

  • Results and statistics

  • Settings

  • Cultures/health care systems

  • Conflict of interest/disclosure statements

  • Funding sources

Clinical question
Clinical Question to Find/Accumulate

For young children, is a smoke detector/fire alarm that uses a recording of his or her mother’s voice more effective at awakening the child and shortening time to evacuation as compared to a standard tone-based smoke detector?

Settings to Find/Accumulate

  • Important for assessment of match between patient and article

  • Most often primary care, tertiary care, hospital, office (UK surgery), nursing home, university medical center, chronic care facilities, home care

  • Compare the “typical” headache seen in above settings

Cultures health care systems
Cultures/health care systems to Find/Accumulate

  • For profit

  • Not for profit

  • Managed care

  • Health maintenance organizations

  • Medicare/Medicaid

  • Veterans Affairs Hospitals

  • Socialized medicine

  • Two tier vs. three tier

Health care systems assignment
Health care systems—assignment to Find/Accumulate

What health care system does each country have?

What “type” of research comes from each country?

  • Canada

  • Israel

  • Sweden

  • United Kingdom

  • Australia

  • The Netherlands

  • United States

Funding sources
Funding Sources to Find/Accumulate

  • Complex and costly issue

  • Competing demands with “for profit” funders vs. “not for profit” funders

  • Kjaergard and Als-Nilesen showed that

    • “in pharmacological and nonpharmacological randomised controlled trials from 12 specialties financial competing interests were significantly associated with authors’ conclusions”

    • “personal, academic and political competing interests were not significantly associated with authors’ conclusions”.

Conflict of interest
Conflict of Interest to Find/Accumulate

Researchers or authors of the study or its report stand to gain (probably financially) from certain results of the study.

Watch for this. Should be included in the article—usually at the end and in a small font.

Differences to Find/Accumulate

All articles same for a few features

  • Question based

  • Preplanned

  • Comparative

  • Patients/participants

  • Settings

  • Cultures/health care systems

  • Funding sources

    Then different….


Therapy to Find/Accumulate

Therapy treatment
Therapy/Treatment to Find/Accumulate

  • More of these types of studies than any other

  • Methodology is pretty well established for conducting trials and presenting results

  • Indexing (and retrieval) excellent

Alternate names
Alternate Names to Find/Accumulate

  • Therapy/Treatment (medicine)

  • Intervention (nursing)

  • Prevention and control

  • Prevention

    • Primary prevention

    • Secondary prevention

    • Tertiary prevention

  • Quality improvement

  • Management???

How to do a therapy trial
How to do a Therapy Trial to Find/Accumulate

  • 2 or more groups

  • Each group gets 1 intervention

  • All groups followed over time

  • At the end of the trial groups compared to assess outcomes

Things to look for in a therapy trial
Things to Look for in a Therapy Trial to Find/Accumulate

Common sense

Allocation concealment

Random allocation



Sensible and important outcomes

Allocation concealment
Allocation Concealment to Find/Accumulate

Done before and during randomization

No one with any influence on who goes into which group can have any knowledge of which group is next

Differences among outcomes if this is not done—more favourable outcomes

Random allocation
Random Allocation to Find/Accumulate

You can randomize:

  • parts of people (e.g., arms, warts)

  • whole people

  • families

  • hospitals or wards (cluster)

  • towns

Methods for random allocation
Methods for Random Allocation to Find/Accumulate


  • Computer methods that do not allow for manipulation of randomization

  • An agency that has no involvement in patient recruitment such as a pharmacy department

  • An external trials office that entails calling into a central registration office and providing details of patient before the randomization is done

  • Sealed, opaque, consecutively numbered envelopes with external checking

Blinding to Find/Accumulate

Individuals involved in a study (e.g., patients, investigators, research staff) do not know who is assigned to treatment or control groups.

Why: Individual expectations can influence study outcomes

Types of blinding
Types of Blinding to Find/Accumulate

Single, double, triple blinding although many more could be listed

Masked, dummy also used

  • Patients

  • Care providers

  • Study personnel

    • Data collectors

    • Outcome assessors

  • Data analysts

  • Report writers

  • Sponsors

Placebo to Find/Accumulate

To aid in blinding some trial participants may get something that is not really a treatment or for “real”

  • Sugar pill in vitamin C trials

  • Sham ultrasound in treating BPH and both real and sham kept “equivalent” by heating pads placed over treatment sites

  • Can be for assessors in addition to patient as in fake blood for patients in a scope vs full surgery trial

Follow up
Follow-up to Find/Accumulate

Concerns the number of participants who completed the study

Look for withdrawals, drop outs, or those who were lost

80% is magic number

Common sense

Clinical question1
Clinical Question to Find/Accumulate

Pain is a complex challenge at the best of times and is especially difficult for children. A hospital committee has been formed that wants to look at alternatives to simply increasing the doses of pain meds. Someone has suggested that video games may distract kids with substantial burns from thinking about their pain. Does the following article support this assertion?

MeSH to Find/Accumulate

Research Comparative study

Clinical protocols Placebos*

Feasibility studies Clinical trials as topic

Pilot projects Clinical trials as topic, I-IV

Research design* Multicenter studies

Double-blind method* Randomized controlled trials Meta-analysis as topic

Patient selection Treatment outcome

Random allocation* Single-blind method

Sample size

Publication types
Publication Types to Find/Accumulate

Clinical trial

Clinical trial, phase I

Clinical trial, phase II

Clinical trial, phase III

Clinical trial, phase IV

Randomized controlled trial

Controlled clinical trial

Multicenter study


Subheadings to Find/Accumulate

Therapy (explodable)



Diet therapy


Therapeutic use (explodable)

Administration and dosage

Textwords to Find/Accumulate

Random: Double blind:

Double-dummy Mask:

Sham: Placebo:

Control: trial: Efficacy


Diagnosis and screening

Diagnosis and Screening to Find/Accumulate

Disease condition present

Diagnosis to Find/Accumulate

This patient has signs and symptoms that suggest diabetes. Does she have it?

Signs and symptoms are present that warrant action.


We are going to check all students in this school to see if the head lice has spread from room 2.

No symptoms are present but because of the population we are going to assess all of them.

Disease/condition Present?

Diagnostic decision
Diagnostic Decision to Find/Accumulate

Three choices after assessing patient:

  • Do nothing for a while—I am not sure at all if the patient has a condition—low probability of a positive diagnosis

  • Treat right away—I am sure beyond any doubt that the patient has the condition—the diagnostic tests will give me no more information

  • Start doing diagnostic tests

Diagnostic decision1
Diagnostic Decision to Find/Accumulate

Probability of disease

0% testing threshold treatment threshold 100%

Wait Test Treat

Diagnostic decision2
Diagnostic Decision to Find/Accumulate

Wait Test Treat

Probability of disease

0% testing threshold  treatment threshold 100%

Positive test results moves    

Negative test results moves    

Diagnosis study example
Diagnosis study—example to Find/Accumulate

Problem: Is this incontinence urge or stress? One treated with drugs, other behaviour

Possible solution: questionnaire vs urologist?

Tested 301 women some incontinence.

Test results after every women got both

75% of time positive when have incontinence

77% of time negative when no incontinence

Diagnosis screening
Diagnosis/Screening to Find/Accumulate

Does this person have or not have a specific disease or condition?

Can questionnaires in family medicine settings screen for:

  • eating disorders

  • Depression

  • domestic violence

  • Alzheimer disease

  • drinking problems

Old test vs new test
Old Test vs New Test to Find/Accumulate

  • Need patients to have spectrum of disease (none to severe)

  • Everyone gets both tests

  • Old test is often invasive, time consuming, costly, or has risks involved

  • Can only do if “gold” test available or can be “rigged”

Things to look for in a diagnosis study
Things to look for in a diagnosis study to Find/Accumulate

Old test vs new test

Blinding of assessment of results of both tests

Blinding of test reading
Blinding of Test Reading to Find/Accumulate

  • Absolutely crucial for evaluation of diagnostic tests

  • Exceptions are things like laboratory tests that do not involve personal biases

  • Blinding is almost NEVER indexed by NLM nor is it included in the abstract of the articles. Often hard to find in the body of the article (methods section)

A good test
A good test…. to Find/Accumulate

…is positive when it should be positive AND negative when it should be negative...

  • Sensitivity and specificity

  • Positive and negative predictive values

  • False positive and negative reactions

  • Positive and negative likelihood ratio

Calculating diagnosis numbers
Calculating diagnosis numbers to Find/Accumulate

Sensitivity and specificity
Sensitivity and Specificity to Find/Accumulate


---test is positive when it should be positive


---test is negative when it should be negative

Predictive values
Predictive Values to Find/Accumulate


---proportion of people with positive results who actually have the disease


---proportion of people with negative results who do NOT have the disease

False positive negative results
False Positive/Negative Results to Find/Accumulate

False positive---

---test is positive when the person does not have the disease (labeling)

False negative---

---test is negative when the person does have the disease (lose time)

Likelihood ratios
Likelihood Ratios to Find/Accumulate

The likelihood ratio for a positive result (LR+) tells you how likely you are to have a positive test if you HAVE the disease

The likelihood ratio for a negative result (LR-) tells you how likely you are to have a negative test if you do NOT have the disease.

Diagnostic decision3
Diagnostic Decision to Find/Accumulate

Wait Test Treat

Probability of disease

testing threshold  treatment threshold

0% 100%

Positive test results moves    

Negative test results moves    

Likelihood ratios are the SLIDERS on this scale!


Accuracy to Find/Accumulate

Bayes theorem


False negative

False positive

Negative predictive value

Positive predictive value

ROC curves

Likelihood ratios






MeSH to Find/Accumulate

Sensitivity a#d specificity*

Predictive values of tests

ROC curves

Diagnostic errors

False negative reactions

False positive reactions

Observer variations

Likelihood functions

Diagnosis, differential*

Reproducibility of results

Publication types1
Publication Types to Find/Accumulate

Subheadings to Find/Accumulate

Diagnosis (explodable)

Diagnostic use (explodable)

Textwords to Find/Accumulate



Predictive value:

False positive

False negative

Likelihood ratio



Prognosis to Find/Accumulate

Prognosis natural history
Prognosis/Natural History to Find/Accumulate

  • What is going to happen to me over the next period of time now that I have been diagnosed with…Patient preference for this type of information and not therapy.

  • Should I treat (or choose to be treated) rather than what is best to treat with. (Scoliosis and prostate cancer)

Prognosis example
Prognosis—Example to Find/Accumulate

  • Do we know the natural history or prognosis for patients who have have been diagnosed with Parkinson disease?

  • 297 patients (181 men) with 1731 visits over 6.4 years (mean) showed a variable course of the disease and its symptoms

Prognosis vs natural history
Prognosis vs Natural History to Find/Accumulate

Traditional difference…

Natural history is what happens to untreated disease over time….

Prognosis is what happens to treated disease…

Prognosis vs natural history1

Natural History to Find/Accumulate

Biological onset at cellular level

Early diagnosis possible (screening)

Usual diagnosis



Usual diagnosis


Prognosis vs Natural History

Prognosis methodology
Prognosis Methodology to Find/Accumulate

Inception cohort study

Group of persons assembled early (or at least at a uniform point) in the timing of their disease and followed over time.

Prognosis methodology1
Prognosis Methodology to Find/Accumulate

Inception cohort study…

  • Follow up 80% or better

  • The follow-up time should be consistent with the demands of the disease

  • Common sense rules

Prognosis numbers
Prognosis Numbers to Find/Accumulate

Raw rates of disease progression (14% had a subsequent myocardial infarction within 5 years of follow up)

Relative risks

Hazards ratios

Odds ratio

Standardized mortality ratios

Prognostic vs risk factors
Prognostic vs Risk Factors to Find/Accumulate

Prognostic factors

Some aspect that an individual has that can modify how that disease will play out—e.g., age of person with CAD, breast cancer stage

Risk factors

Some aspect that an individual has that may affect whether that person is more or less prone to acquire a disease or condition, e.g., family history of CAD, Al and Alzheimer’s

Prognosis terms
Prognosis Terms to Find/Accumulate

Adjustment Natural History

Cohort study Prevalence

Inception Prognosis

Incidence Prognostic factor

Longitudinal studies Prospective studies

Morbidity Risk factors

Mortality rates, ratios

MeSH to Find/Accumulate

Cohort studies* Survival XXXXXX

longitudinal studies

prospective studies

follow-up studies






Survival analysis

Disease progression*

Time factors*

Age factors*

Sex factors*

Publication types2
Publication Types to Find/Accumulate

Subheadings to Find/Accumulate


Epidemiology (sometimes)

Textwords to Find/Accumulate

Natural history Prognos:

Inception cohort Clinical course

Predict: Predictive value

Outcome Prognostic factor


Alternative source
Alternative Source to Find/Accumulate

For short-term prognosis information, randomized controlled trials often have information that can be used when desperate. This is especially true for placebo-controlled or usual-care arms of studies.

Etiology causation harm

Etiology/Causation/Harm to Find/Accumulate

Etiology causation harm1
Etiology/Causation/Harm to Find/Accumulate

Etiology or causation is the study of what causes, or what increases or decreases the risk for a disease or condition. This can be either positive (protective) or negative (harmful).

e.g., social support at work is associated with fewer short-term psychiatric absences

giving up driving is associated with depressive symptoms in older adults.

Etiology causation harm2
Etiology/Causation/Harm to Find/Accumulate

Generally looking at

  • Exposures to causative/protective agents

  • Outcomes

  • Time (can be now, in the future, or looking back)

  • Other factors that can affect outcomes

  • Need a lot of creativity and common sense

  • Many long-term etiology studies come from countries with socialized medicine.

Q does the use of cell phones while driving cause accidents
Q: Does the use of cell phones while driving cause accidents?



What groups?

Q does the use of cell phones while driving cause accidents1
Q: Does the use of cell phones while driving cause accidents?

Randomized controlled trial

large group of persons who

are told whether they will

use cell phone during driving for long time…..

Q does the use of cell phones while driving cause accidents2
Q: Does the use of cell phones while driving cause accidents?

Cohort study

a group of persons who uses phones while driving is compared with another group who do not use phones while driving…

Q does the use of cell phones while driving cause accidents3
Q: Does the use of cell phones while driving cause accidents?

Case-control study

people who have had automobile accidents are compared with people who have not had accidents and both groups are studied to see who used phones during driving…

Q does the use of cell phones while driving cause accidents4
Q: Does the use of cell phones while driving cause accidents?

Statistically adjusted groups (cross sectional study)

Data on some persons with automobile accidents were collected and compared with data from some persons with no accidents and both groups have cell phone use rates determined….

Etiology study types
Etiology study types accidents?

Type Time Quality Number

RCT future ***** *

Cohort now *** ***

Case-control past * *****

Statistically past - infinity

adjusted groups

(cross sectional studies)

Etiology issues
Etiology Issues accidents?

  • Association is not necessarily causation

  • Ethics

  • Logistics

  • Blinding

  • 2 C’s—Common sense and Creativity

Association vs causation
Association vs Causation accidents?

Just because two things occur at the same time does not mean that they are causal--

  • Higher intake of ice cream and higher rates of drowning occur in the summer—linked? Don’t think so…...

  • Poor quality health and low socioeconomic status……

Ethics accidents?

Sometimes you cannot allocate persons to exposures

  • Smoking

  • Divorce

  • Genetic disposition

  • High socioeconomic status

  • Can do this however for drug adverse effects, social programs

Logistics accidents?

Groups need to be as similar as possible to account for confounding

  • For power line studies…..

  • Smoking and drinking issues…

  • Another set of “intertwined” issues?

    Need for creative problem solving

Blinding accidents?

Blinding is crucial especially for the case-control studies.

Blinding must be 2-fold here:

  • forming groups without knowing exposures (cell phone use in cars)

  • assessing exposure without knowing disease/exposure status (automobile accidents)

Relative risk rr
Relative Risk (RR) accidents?

Used for RCTs and cohort studies (prospective)

Comparison of rates of developing the disease/ condition in the 2 groups of people with and without the risk factor (We know exposures)

Weight gain and coronary heart disease in women (400 women in our sample)

if gain > 15 lb 106/200

if gain < 15 lb 56/200

RR= (106/200)/(56/200) = 1.9


Association accidents?



Case-control study

Cohort study


Cross sectional studies

Odds ratio

Prospective studies

Relative risk

Retrospective studies


Risk factors


MeSH accidents?

Case-control studies*

Retrospective studies

Cohort studies*

Longitudinal studies

Prospective studies

Follow-up studies

Cross sectional studies


Risk assessment

Risk factors

Odds ratio

Publication types3
Publication Types accidents?

Subheadings accidents?

Etiology (explodable)

Epidemiology (for distributions, causes, and attributes of disease)

Textwords accidents?


Case control


Odds ratio

Causation or causal:

Relative risk

Etiol: or Aetiol:

Systematic reviews and meta analyses
Systematic Reviews and Meta-Analyses accidents?

Two types of review articles exist:

  • Narrative reviews

  • Systematic reviews

    • Systematic reviews

    • Meta-analyses of study data

    • Meta-analyses using individual patient data

Systematic reviews
Systematic Reviews accidents?

  • Medicine did not “invent” or develop

  • Fully developed by psychology, education, and related disciplines

  • Early 1900s

    • Pearson and enteric fever in the British Army

    • NIH (Hygiene Laboratory) report

  • People:

    • Eugene Glass was one of the first developers

    • Tom Chalmers was one of the first medical developers (On Golden Pond)

    • Archie Cochrane plus Tom and Iain Chalmers

Systematic vs narrative

Team approach accidents?

Narrow specific purpose

Methods drive the process

Inclusion/exclusion criteria

Clinically useful

One major author

Broad purpose may not always be stated

No methods on how articles picked

No inclusion/ exclusion criteria

Ecuationally useful

Systematic vs Narrative

Systematic reviews1
Systematic Reviews accidents?

Must have

  • Purpose why done

  • Search strategy in detail

  • Inclusion and exclusion criteria for study selection

Why do one
Why do one? accidents?

  • Too much data

  • Too little data

  • Resolve discrepancies

  • “tighten up” estimates of effects of treatments, exposures, etc

  • Analyze patient subgroups

  • Plan for new studies—similar or “next generation” studies

  • Provide data for certain types of studies such as economic studies, decision analyses, or clinical practice guidelines

Steps accidents?

  • Problem formulation

  • Identify and select articles (searching and retrieval)

  • Data extraction

  • Analysis and decision if meta-analysis is appropriate (clinical and statistical test)

  • Presentation of results

Statistical concepts
Statistical Concepts accidents?





Effect sizes

Statistical concepts1
Statistical Concepts accidents?

Same as for other study types but often qualified with “combining” phrases

combined odds ratio

pooled relative risk

weighted hazards ratio

typical mortality rate

summary estimates sensitivity

Medline difference
MEDLINE Difference accidents?

Simplistic difference (and hard to differentiate between the two)

Review—does a summary of existing knowledge

Meta-analysis—produces new knowledge

Meta analysis mesh
Meta-analysis MeSH accidents?

A quantitative method of combining the results of independent studies (usually drawn from the published literature) and synthesizing summaries and conclusions which may be used to evaluate therapeutic effectiveness, plan new studies, etc., with application chiefly in the areas of research and medicine.

Clinical trials overview, data pooling,

Meta analysis previous indexing
Meta-analysis Previous Indexing accidents?

Follow up studies

Outcome and process assessment


Research design


Meta analysis publication type
Meta-analysis Publication Type accidents?

Works consisting of studies using a quantitative method of combining the results of independent studies (usually drawn from the published literature) and synthesizing summaries and conclusions which may be used to evaluate therapeutic effectiveness, plan new studies, etc. It is often an overview of clinical trials. It is usually called a meta-analysis by the author or sponsoring body and should be differentiated from reviews of literature.

Review literature mesh
Review Literature MeSH accidents?

Published materials which provide an examination of recent or current literature. Review articles can cover a wide range of subject matter at various levels of completeness and comprehensiveness based on analyses of literature that may include research findings. The review may reflect the state of the art. It also includes reviews as a literary form.

Systematic reviews terms

Effect sizes accidents?



Meta-analysis of study data

Meta-analysis of individual pt data


Narrative review

Summary estimates

Systematic reviews



Systematic Reviews Terms

MeSH accidents?

Randomized controlled trials

Clinical trials

Controlled trials


Publication types4
Publication Types accidents?


Review iff

ANDed with MeSH or textwords

Subheadings accidents?


Meta-analy: accidents?



Systematic review or overview

Overview (careful)

Quantitative review or overview

Methodologic: review or overview








Food for thought
Food for Thought accidents?

Sometimes a rare condition that is being written up as a case report will include a substantial amount of background material. Don’t necessarily cross out a case-report if you are desperate for review type material.

Alternative sources
Alternative Sources accidents?

PubMed Clinical Queries—Review articles

Cochrane—note only for RCTS

  • Cochrane reviews

  • Dare

  • Clinical Trials

    DARE (Database of Reviews of Effectiveness—librarian run project)

    Campbell Collaboration

    TRIP database—one stop shopping

Systematic reviews quiz
Systematic Reviews Quiz accidents?

1 Systematic reviews are the same as ordinary reviews only bigger?

Based on: Petticrew M. Systematic reviews from astronomy to zoology: myths and misconceptions. BMJ. 2001;322:98-101.

Systematic reviews quiz1
Systematic Reviews Quiz accidents?

2 Systematic reviews contain only randomized controlled trials.

Systematic reviews quiz2
Systematic Reviews Quiz accidents?

3 Only medical topics can be studied in systematic reviews.

  • More money on schools improved educational outcomes?

  • Do men or women make better leaders?

  • Does the sexual orientation of the parent matter to the child’s well being?

  • Are fathers more likely to treat their children differently than mothers?

  • Is job absenteeism an indicator of job dissatisfaction?

  • Are jurors influenced by the race of the defendants?

  • Is there a relation between poverty and violence?

Systematic reviews quiz3
Systematic Reviews Quiz accidents?

4 Systematic reviews can be done well without experienced information personnel or good library support.

Systematic reviews quiz4
Systematic Reviews Quiz accidents?

5 Systematic reviews have no relevance to the real world

Systematic reviews quiz5
Systematic Reviews Quiz accidents?

6 Systematic review necessarily involve statistical syntheses.

Systematic reviews quiz6
Systematic Reviews Quiz accidents?

7 Systematic reviews have to be done by experts with a lot of training in methodologies.

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Systematic Reviews Quiz accidents?

8 Systematic reviews are a substitute for doing good quality individual studies.

Systematic reviews quiz8
Systematic Reviews Quiz accidents?

9 You can be part of a team doing a systematic review.