Research evidence (knowledge base)
Doctor's Clinical Expertise
what is the the theory of evidence based
Patient's Preferences and values
pratice?
all overlap
what are curated databases considered? deep web
-case reports, cases series
-observational studies: cross-sectional, case-control, cohort
what are the primary (unfiltered) sources of
-randomized control trials
evidence? what does "primary/ unfiltered"
mean?
the authors collected new data or used previous data in a new way (still pass through
peer-review)
- clinical practice guidelines
what are the secondary (filtered) sources of - Systematic reviews (NOT literature reviews)
evidence? what does "secondary/ filtered" - Meta-analyses
mean?
the authors review data from previously published studies
arrange the following in the order of the (Base) -case reports, case series
evidence hierarchy (from base to apex): -observational studies
-randomized controlled trials
-clinical practice guidelines -clinical practice guidelines
-case reports, case series -systematic reviews
-meta-analyses (apex) -meta-analyses
-systematic reviews
-randomized controlled trials
-observational studies
natural experiments, no intervention except observational studies
usual care, new data is collected or
previous data from a registry or database is
used in a new way describes
, what type of study can continue for years- observational studies
decades and may include 10's-100,000's of
participants
a) prevalence- count new cases during a specific perdio
Obs 1: cross-sectional/ longitudinal :
b) incidence- determine the rate of new cases
Why do this type of study?
estimate the expected number of cases, prepare for medical needs of the
community
a) case group and control group
Obs 2: Retrospective case control:
b) look back for common exposure
why do this type of study?
make hypotheses about possible cause (etiology)
why do/ did only see of the exposed get sick?
a) case group and control group
Obs 3: Prospective cohort: b) look forward for development
Why do this type of study? make predictions about outcomes such as:
1. disasters: what needs are anticipated
2. medical (exposure): what is the prognosis
counting (ds) cases , seeing the new cases within x amount of time and determining
what is an example of an Obs 1 study?
the rate of infection
disease outbreak on a cruise ship: how many people got it, why did they get it
what is an example of an Obs 2 study? (stomach bug with everyone who at bad shrimp on the Tuesday, no one else go sick
except those etc...)
tracking the effects of smoking to see what developed in smokers vs non smokers to
see what happens
what is an example of Obs 3 study? or
hurricane preparedness after impact: what needs to be the baseline for
preparedness
what is a true human experiment (with Randomized control trials
consent), used to test medical hypotheses,
control vs tx groups OR gold standard vs
new tx groups?
confirm results of clinical trials (safety, efficacy)
why do a RCT?
provide date used in future secondary studies
provide practice consistency to physicians (and save them the work of finding the
why is professional recommendation of a
evidence)
best practice based on secondary
evidence and or RCTs?
provide evidence to support billing claims and legal challenges
what is an intense, exhaustive, review of systematic review
previous studies to verify they were done
properly and their conclusions are valid,
generally done by committees that include
experts on the medical condition, on
statistics, and on research design?