Evidence Based Medicine – Introduction

& Information Resources

Dr. Suman Bhusan BhattacharyyaMBBS, ADHA, MBA

&http://www.cebm.net/

An Evaluation

• What?• Why?• Where?• How?• Pain areas…

Evidence Based Medicine– What?

• Widely credited to have been coined by Dr. David Eddy of Kaiser Permanente

• It is believed that its philosophical base dates back to the sceptics of post-revolutionary France (Xavier Bichat, Pierre Louis, François Magendie)

• May have origins in China, B.C.• The conscientious, explicit and judicious use of current

best evidence in making clinical decisions about the care of individual patients (Dr. David Sackett, 1996)

Evidence Based Medicine- When?

• There is evidence that something works, is good and benefits the patient, do it

• There is evidence that something does not work, is harmful, does not benefit the patient, do not do it

• There is insufficient evidence, be conservative, relying on individual clinician expertise

Evidence Based Practice- What?

Any practice that applies up-to-date information from relevant and valid research about the usefulness of various diagnostic tests or the predictive power of prognostic factors or the beneficence of a particular treatment method across healthcare, including education, practice management and health economics, it is said to be EBM-enabled.

Evidence Based Enablement, but…

Mere application of evidence based medicine is in itself simply not good enough. The end results need to be validated. This is done by performing outcomes analysis, preferably on a continuous basis

Evidence Based Practice– Why?

• The old way of depending on a combination of informed guesswork, unsystematic observation, common sense, the consensus views of clinical experts, and the so-called “standard and accepted practice”, meaning the treatments and procedures used by most other clinicians in a local community – was fine, but with the addition of enormous amounts of information every day, things are threatening to “get out of control”.

• So, is this way “the only way”?

The Pain Areas… • 27 Kg of guidelines, • 3000+ new papers per day, • 1000 new Medline articles, • 46 randomized clinical trials• The number of biomedical journals alone doubling since 1970. • Average workload for a clinician of anything between 100 to 200

consultations a week resulting in 5000 to 10000 per year. • Add to it the difficulty of relying solely on experience while using 2

million pieces of information all stored in ones memory, ever increasing pressures to provide value-for-money services, raised patient demands and expectations, pressures due to a myriad of obtrusive and mostly confusing regulatory compliances, and rapidly altering business demands.

• Hmmm…

The Pain Areas… [Contd.]

Every encounter with a patient identifies gaps in our knowledge about the etiology, diagnosis, prognosis, or therapy of their illness. Recent research reveals that even as seasoned clinicians we generate about five knowledge “needs” for every in-patient encounter, and two “needs” for every three out-patients encounters.

The Pain Areas… a plausible answer

• To bridge these gaps and fulfill the “needs”, we need to practice evidence based medicine, and to evaluate the best evidence that evidence based medicine is supposed to reveal we need to perform outcomes analysis

• Practicing medicine based on best evidence in the form of clinical protocols helps as a valid legal cover in malpractice suits

Best Evidence…

• Current best evidence is up-to-date information from relevant, valid research about the effects of different forms of healthcare, the potential for harm from exposure to particular agents, the accuracy of diagnostic tests, and the predictive power of prognostic factors.

PICO – well built clinical questions

Evidence Based Medicine – How? The way of seven A’s…

Assess the patient a clinical conundrum or question that arises out of the clinical examination

Ask the patient the care provider needs to construct a well-built clinical question from the findings in step 1

Access the information the appropriate resources needs to be selected and searched for the answer to the question framed in step 2

Appraise the evidence the information gathered in step 3 needs to be critically appraised using the various indices for its validity and applicability to the patient’s problems

Apply the findings the validated evidence needs to be integrated with clinical expertise and patient preferences and then applied as required

Assess the outcomes the performance of the evidence with the patient needs to be evaluated

Add the knowledge the information so gathered added to the clinician’s knowledge base for future reference to best evidence in similar problems

Evidence Based Medicine – The Types

• Diagnostic– Here the importance of various observations,

value of diagnostic tests, etc. are evaluated in ruling in or out a diagnosis

• Treatment– Here the value of a treatment method or the

necessity of a particular medication or procedure is determined

Evidence Based Balance Sheet

1. Examine the evidence that a treatment is effective.

2. If so, then determine the magnitude of its benefits, harms, and costs.

An evidence based balance sheet is an important tool that supports the practice of evidence based medicine.

Evidence Based Balance Sheet• Display in a compact form the evidence as

quantitative estimates of the effects of alternative treatments on all the important outcomes

• The decision-makers can more easily grasp the consequences of the different options they face.

• Specially useful for informed shared decision-making between physicians and patients.

Developing an Evidence Based Balance Sheet – The 4 Main Steps

1. Identification of the alternative treatments that are available to the patient

2. Identification of the health outcomes (i.e., the outcomes that can be experienced by, and are important to, the people who will receive the treatments) that are affected by the treatments

3. Estimation of the probabilities or magnitudes of each of the health outcomes, for each of the alternative treatments

4. Displaying the information in a table

EBM Balance Sheet – An ExampleOne-year probabilities of outcomes associated with Alendronate 5 mg vs. no drug, for a 55-year-old average-risk woman.

Item  No Drug Drug Difference NNT

Hip fracture .00046 .00032 .00014 7143

Wrist fracture .00316 .00223 .00093 1078

Spine fracture .00144 .00084 .0003 3322

Long-term benefits 0 ? ? ?

Inconvenience 1 0 1 1

Gastric distress 30% 0 30% 3

Long-term Harms 0 ? ? ?

Cost of drug $0 $308 +$308  

Expected cost of treatment $220 $203 -$17  

Net cost $220 $511 +$291  

Problems associated with Evidence Based Practice

Problems Solutions/Workarounds

Resources and commitments in terms of time and money that needs to be delivered away from actual patient care

Evaluate against opportunity cost, follow-on and abandonment option costs. Evidence based practice wins hands down as a strategic investment

Finding and evaluating the evidence is costly in terms of time

Use EPR

Lack of skills in computer use and locating evidence Train personnel. This is not an issue with the generation next.

Resources needed to acquire and maintain databases Availability in electronic form and increased usage will bring the prices down

Searching may only result in discovering gaps in medical knowledge

One must seriously doubt our capabilities and question our insecurities

Poor indexing may lead to frustration of futile literature searches

Use online searches and make all literature available searchable online

The quality and quantity of research mostly unknown Use refined studies performed real-time using EPR

Demands a high degree of statistics knowledge Use EPR that have the calculations as well as their interpretations built-in

Viewed as a form of rationing Evidence based medicine is about improving the quality of patient care. It is just as likely to show that effective interventions are underused as to show that ineffective procedures are over-used

EBM in Clinical Protocols

• Clinical protocols need to be made based on the current best evidence

• These protocols must undergo continuous revalidation in order to continue to be relevant according to the current best evidence

• Protocols change according to triage assessments and specialty – so they need to be user and problem-specific

Push, Pull, Prompt …ways to deal with

too much information

Evidence-Based Information Resources

Evolution of EBM InfoPreEBM: Passive diffusion (“publish it and they will come”)Early EBM: Pull diffusion (“teach them to read it and they will come”)Current EBM: Push diffusion (“read it for them and send it to them”)Future EBM: Prompt diffusion (“read it for them, connect it to their individual patients, prompt them and their patients”)

Information in the Internet Age*

Information in the Internet age may be constrained by a variant of Malthus’ law: • The amount of information is growing exponentially, but our attention is not.• A wealth of information creates a poverty of attention. • The low cost of production of poor quality information results in high quality information being drowned out.• The cost of finding specific information rises as the amount of information increases.

*Coiera E. Information economics and the internet. J Am Med Inform Assoc 2000;7:215-21.

The Slippery Slope

years since graduation

r = -0.54p<0.001

...

...

. ... . .... .

....

....

.....

...knowledgeof current best care

100%

0%

50%

Choudhry, Fletcher and Soumerai, Ann Intern Med 2005;142:260-73-94% of 62 studies found decreasing competence for at least some tasks, with increasing physician age.

The McMaster PLUS project

• only a tiny proportion of all research is “ready for application”

• only a tiny fraction of the “ready” research is

“relevant” to the practice of a given clinician

• only a tiny proportion of the “relevant” research for a given practitioner is “interesting” in the sense of being something new, important, and actionable.

60,000 articles/yrfrom 120 journals

~3,500 articles/yrmeet critical appraisaland content criteria(95% noise reduction)

Evidence-Based Journals

Critical Appraisal Filters

~3,500 articles/yr meet critical appraisaland content criteria(95% noise reduction)

McMaster PLUS Project

Clinical Relevancy Filter (MORE)

~25 articles/yr for clinicians (99.95%noise reduction)

~5-50 articles/yr for authors of evidence-based clinical topic reviews

McMaster Online Rating of Evidence: >6000 practicing clinicians

http://bmjupdates.mcmaster.ca

User End

• Users sign up according to discipline• Users control relevance and flow• Users can change disciplines at any time, and can sign up for

as many as they wish• Users can search according to discipline – or not• Users can access PubMed Clinical Queries• (We can monitor individual use, if agreed)

Dear Dr. Haynes,

We want to alert you to NEW articles in the PLUS system. These articles that have received very high relevancy and newsworthiness scores:

1. Brazg R, et al. Effect of adding sitagliptin, a dipeptidyl peptidase-4 inhibitor, to metformin on 24-h glycaemic control and beta-cell function in patients with type 2 diabetes. Diabetes Obes Metab. 2007;9:186-93.

 

Rated by: IM/General (patients referred from Primary Care)

Relevance: 5 of 7 Newsworthiness: 5 of 7

 

We hope that you will find these articles of value in your clinical practice.

Best wishes from the PLUS Team

CONCLUSIONS: In this 24-week study, once-daily sitagliptin monotherapy improved glycemic control in the fasting and postprandial states {vs placebo}, improved measures of beta-cell function, and was well tolerated in patients with type 2 diabetes.

Medscape Best Evidence Alerts

Free at https://profreg.medscape.com/px/newsletter.do

Systems

Summaries

Synopses

Syntheses

Studies

Examples

Computerized decision support

Evidence-based textbooks

Evidence-based journal abstracts

Systematic reviews

Original journal articles

The evolution of information resources for evidence-based decisions

Premier evidence resources

Systems: EMR with decision supportSummaries: Clinical Evidence, PIER, UpToDate, DynamedSynopses: ACP Journal Club, EBMSyntheses: via BMJUpdates+Studies: via BMJUpdates+, PubMed Clinical Queries

58 year old obese male with …type 2 diabetes mellitus …A1c 9% (elevated) on glyburide and rosiglitazone, with metformin intolerance…continuing to gain weight…very reluctant to take insulin

Can the new ‘incretin therapies’ (eg, exenatide, pramlintide or sitagliptin)

help?

SystemsSummariesSynopsesSyntheses

Studies

For type 2 diabetes, what are the effects- good and bad -

of incretin therapy?

Systems: no Computerized Decision SupportSummaries: in UTD, PIER, Dynamed, not CESynopses: sitagliptin in ACP JCSyntheses: one for pramlintide in BMJUpdates+Studies: exenatide, pramlintide, sitagliptin in UTD, PIER, CE, BMJUpdates+; more on exenatide, pramlintide and sitagliptin in Clinical Queries

Januvia is approved for use by people with type 2 diabetes that can't be controlled adequately with diet and exercise.

Section updated June 2007

Comments on exenatide, pramlintide, sitagliptin, with drug monographs for each

“Many questions remain unanswered regarding clinical use and long-term outcomes with these drugs.”

US$5 per pill

• Includes exenatide, pramlintide, and sitagliptin, with drug monographs for each

• “Consider metformin as a first-line agent because it causes less hypoglycemia and weight gain, along with possible improvements in cardiovascular risk.”

• “Consider other oral agents, such as sulfonylureas, thiazolidinediones, and DPP-IV inhibitors {sitagliptin}, as reasonable first-line agents, although some are costly and the long-term benefits of these drugs have not been well studied.”

CONCLUSIONS: Incretin therapy offers an alternative option to currently available hypoglycemic agents for nonpregnant adults with type 2 diabetes, with modest efficacy and a favorable weight-change profile. Careful postmarketing surveillance for adverse effects, especially among the DPP4 inhibitors, and continued evaluation in longer-term studies and in clinical practice are required to determine the role of this new class among current pharmacotherapies for type 2 diabetes.

Survey of traditional textbooks of medicine

• Harrison’s Textbook – nothing • Books@Ovid – nothing• Kelley’s Textbook - nothing

My conclusions about exenatide, pramlintide, sitagliptin

• Interesting new options for diabetes• Not well studied (eg, no comparisons with

current best medications)• Exenatide and pramlintide would likely be

out for this patient (injections)• Sitagliptin is a possibility, but not until better

known options tried (acarbose, Avandamet, repaglinide)

Finding evidence when you’re not sure where to look

• TRIP• SUMSEARCH• CLINICAL QUERIES

(Pick One)

To keep up with evidence

• Pull

• Push

• Prompt…some labs and EMRs with a credible evidence-based pedigree (Zynx)

Systems

Summaries

Synopses

Syntheses

Studies

Thank You!