logistic regression Flashcards
what is the purpose of logistic regression
- one or more categorical exposures
- one or more continous exposures
- a combiantion of teh above
- model the realtionship between an binary outcome and its predictor variables
- predict the proabbi;ty of an event happening
what test can be used ot look at the risk of hypertension depend on sex
pearson chi-squared
why use logistic regression
chi2 cant adjust confounders, so results can be biased
logistic regression can handle a lot more variables of any kind
what does OR= 1 mean
if disease/condition/event is equally likely to happen in exposed and nonexposed subjects
what does OR>1 mean
more likely to happen in exposed
what does 0<OR<1 mean
less likely to happen when exposed
what is logistic regression
logostic regression anyalsis is based on the log transformation of the odds
what is polytomous regression
catergorical reponse variable with 3+ groups hvaing a natural ordering
what is teh princiople of general linear modelling
transform any outcome varibale into a continous normal equalent then fit a linear regression
what do odds ratio allow
easy to esitamate and compare, allowing to detect favtors taht have an impact on the event of interest
what are odds
alternative metric to measure incidence or prevalence
what do you need for logistic regression
- a conntinous outcome and normal distribution
what is the point of logistic regression
when you have binary data that needs to be continous
what cant chi squared do
cant adjust confonders so results can be biased
what happens in rare conditions
risk is approx the same as the odds
