EBM Intro Flashcards
Who established the core principles of EBM?
Dr David Sackett
What is EBM?
the integration of best research evidence with clinical expertise and patient values
Why do we need EBM?
what we learn in school will not last forever
-new therapies
-new indications
-new formulations
-new “experts”
What are the 5 steps of EBM?
ask (develop your question)
acquire (find the best evidence)
appraise (critically evaluate the evidence for validity and usefulness)
apply (use results in your practice)
assess (evaluate your performance)
What are the components of the research question (step 1: ask)?
PICO
population
intervention
comparison
outcome
What are some tools for literature searching (step 2: acquire)?
Medline
PubMed
Cochrane Database (systematic reviews)
Google Scholar (be careful)
Google (be careful)
Differentiate between descriptive and analytic study designs.
descriptive: snapshot in time, no intervention
-survey (cross-sectional)
-qualitative
analytic: intervention, following throughout time
-experimental: randomized (parallel or crossover), non-randomized
-observational: cohort, cross-sectional, case-control
What does it mean to appraise (step 3)?
the process of carefully and systematically examining research to judge its validity, results, and relevance
Why is critical appraisal important?
its no longer possible to believe much of the clinical research that is published
much of the scientific literature may be untrue
many studies have small sample sizes, tiny effects, invalid exploratory analyses, and conflicts of interest
study results are not always: valid, safe, and useful
True or false: the number of journals indexed on PubMed has been declining
false
the number of journals has been increasing fast
Differentiate between internal validity and external validity.
internal validity:
-are the results due to the intervention or something else?
external validity:
-are the results applicable (generalizable) to other populations, settings, and time?
-depends on study population and setting
What are the 3 major threats to internal validity?
chance
confounding
bias
What is chance?
random error
-inherent in all measurements
-the more there is, the less precise the results
What is bias?
any systematic error in a study that results in an incorrect estimate of the association between the intervention or exposure and the outcome
problems with the way a study was designed, conducted, or analyzed that leads to incorrect results or conclusions
What is confounding?
a confusion of effects
-factor(s) other than the intervention or exposure influences the observed outcome
-the factor must be linked to the exposure and the outcome
