DISLE: Evidence Based Medicine Midterm Review

What is the definition of evidence based medicine?

"...the conscientious, explicit, and judicious use of current best evidence in making decisions about the care of individual patients."

What is EBM the integration of?

• Best evidence

• Clinical expertise

• Patient values

Why is EBM practices?

• Underuse of effective care

• Continued use of interventions that are proven ineffective or harmful

• Overuse of services that are of high supply

• Variation in outcomes attributable to quality of care

What is the general hierarchy of clinical drug studies?

 TOP: Systematic review / Meta-analysis (SR/MA)

 Randomized controlled trials (RCT)

 Cohort studies

 Case control

 Case series

 BOTTOM: Consensus (or expert) opinion

What are the four general principles of grading in EBM?

High

Moderate

Low

Very Low

High

Meta Analysis of multiple well-designed RCTs (I²=0%)

Moderate

Individual RCTs with validated/clinically important outcomes

Low

Observational studies or meta-analysis with high heterogeneity 

Very low

Case series, expert opinion

Systematic review

• Basis is multiple clinical trials

• Studies derived from an extensive and structured search of the literature

• Explicit study protocol (inclusion/exclusion criteria)

• Validity of studies assessed

Meta-analysis

• All elements of systematic review

• Also: 

  • All studies are statistically combined

  • Individual study results are integrated into a single result

• Not always possible

PRISMA

Preferred Reporting Items for Systematic Reviews and Meta Analysis

What is the purpose of the PRISMA guidelines?

To provide proper procedures for conducting a meta-analysis and to standardize the methods of reporting a meta-analysis

Results of individual studies

For all outcome present for each study

Publication bias

Arises when trials with statistically significant results are more likely to be published and cited and are preferentially published in English language journals and those indexed in Medline