Lecture 8 - Harm Flashcards
equation for incidence
NEW cases / # people at RISK;
in a specified period of time
prevalence equation
EXISTING cases / TOTAL # people
what kind of study calculates incidence?
cohort
case fatality equation
people dying due to disease / # people WITH DISEASE
attack rate equation:
people CONTRACTING a disease / # people AT RISK
Cohort vs Case control:
which is better (ie higher at heirarchy of eveidence)?
which starts with patients that are the same (ie don’t have disease)?
which starts with patients with disease vs control?
cohort;
cohort (ie think o and o are same);
case control (think A and O are different)
cohort vs case control: which assess exposure status? which assess outcome based off of exposure? which can find incidence? which is associated with recall bias?
exposure status = case control;
outcome = cohort;
incidence = cohort;
recall bias = case control
cohort vs case control:
which uses ODDs ratio?
which uses relative risk?
case control;
cohort (ie think o and o are related)
in a harm 2 x 2 table, with disease on top and exposure on the side, relative risk uses _____ (ie rows or columns), while ODDs ratio uses _____
rows (think Rows for Relative Risk);
columns
a ____ of 3.0 means outcome occurs 3 times more often in those exposed vs unexposed
RR
when discussing Harm, we expect RR to be ___ Than 1
greater
an ____ of 3.0 means that diseased patients were 3 times more likely to have been exposed than were control patients
OR
equation for attributable risk
AR = risk of disease in exposed - risk of diseased in unexposed
also equal to (RR-1)/RR
equation for number needed to harm
1 / AR
to be an meaningful result, odds ratio (case control) should be greater than ____;
Relative risk (cohort) should be greater than _____
4;
3