Align Module Flashcards
what is the best evidence for when looking at interventions and screening, prevention, and therapy?
best is systematic reviews for RCTS
what are the parts of PICO
population
intervention
comparison
outcomes
what is equipoise
belief that the new treatment will be helpful and positive
what is placebo
sham treatment, sugar pill, etc
what is masking/blidning
making it so someone doesnt now that something is happening or what itnervention or placebo they are getting
what is bias?
all different types. that make it so that the study isnt fair
can blinding be bad?
yes if the treatment is dangerous, or if the resutls are really good. you would want to know
what is attrition bias?
a form of selection bias
how can you stop the attrition bias?
intent to treat analysis!
what is the highest level of evidence?
meta analysis
what is the lowest level of evidence
unsystematic clinical observations
what is the order of evidence in total
1) meta analysis
2) Systematic review of RCTS
3) single RCT
4) systematic review of controlled observational study
5) single controlled observational study (cohort is better than case control)
6) single uncontrlled observational study (case series better than case report) btu the rest in line with cross sectional and ecological
7) physiologic studies (blood pressure, etc)
8) unsystematic clinical observations (anecdotes, subjectives)
what is an ecologic observational study?
summaries, groups and aggregate measures
no causation is found
what is a case report and case series?
not controlled, new unusual occurances
what is cross sectional study? s
surveys, prevalance
sample at a point in time, data collected on exposures and outcomes
what is case control
begins with people with and without the condition. compared on an exposure they had in the past
what is cohort?
follow up, longitudinal
groups followed over time to see if a symptom develops
what is a hazard ratio?
similar to releative risk, risk ratio
often used interchangably with relative risk even though its calculated differently
calculated using survival analysis
relativ erisk calculates risk over a certain time span
hazard ratio calculates risk at a particularpoint in time
sinterpreted in a similar fassion
what does a relative risk of 1 mean
no difference
what does a relative risk >1 mean
higher (one is more harmful than the other)
what is relative risk?
probability of an outcome in an exposed group to the probability of an outcome in an unexposed group
what types of studies reveal clusters?
cross sectional
