day 9 slides Flashcards
P-value explains the likelihood that what is true?
the null hypothesis
When do you reject the null hypothesis?
when p-value is less than 0.05
What does Cohen’s D explain?
practical significance instead of just statistical significance
What is Bonferonni correction?
helps you to control for confounding errors; take the p-value and divide by the number of items you are evaluating
type 1 error is a ____?
false positive
type II error is a ____?
false negative
greater power = more ____
confidence
whenever we up the sample size, what happens to power?
increases
if we decrease standard deviation, what happens to power?
increase power
the larger the effect size, the greater the ____
power
Effect size of less than .2 is considered ____
small
Effect size of .2-.5 is considered _____
medium range
Effect size greater than .8 is considered ____
large
What is mortality?
number of deaths, person-centric
what is morbidity?
state of being symptomatic, illness-centric
What is incidence?
new cases per population at risk
What does incidence tell you?
tells you risk of contracting the disease
Incidence does or does not depend on duration of illness?
does not
incidence reporting is preferred when studying what?
cause and effect short-term diseases
what is prevalanece?
all cases in the. population at risk, new and old cases
what does prevalence tell you?
tells you how widespread the disease is
Prevalence does or does not depend on the duration of disease?
does, a long duration will eventually increase the prevalence
prevalence reporting is preferred when studying what?
estimating population based burden of chronic disease or attribute (example: smoking)
what are used to quantify the quality of a study?
critical appraisal tools
