Epidemiology Flashcards Preview

POM > Epidemiology > Flashcards

Flashcards in Epidemiology Deck (11):
1

What are the parts of PICO?

-patients (population)
-intervention (experimental group)
-comparison (control group)
-outcome

2

What drags down sensitivity?

False negatives

Sensitivity + FNR = 100%

3

Formula and definition of sensitivity

Sensitivity = a / (a+c)

-true positive rate
-what percent of ppl w/ the disease get a positive test result

4

Formula and definition of specificity

Specificity = d / (b+d)

-true negative rate
-what percent of ppl w/o the disease get a negative result

5

What is the real value of interest of a test result

Positive predictive value (which = posttest probability)

-value of ppl w/ a positive result who truly have teh disease

6

Formula and definition of PPV

+PV = a / (a+b)

-proportion of ppl w/ a positive test result who actually have the disease

7

Formula and definition of NPV

-PV = d / (c+d)

-proportion of ppl w/ a negative test result who truly don't have the disease

8

What result from what kind of test would rule a diagnosis in ?

SpPIN

-positive result on a specific test (low false positives) rules in a diagnosis

9

What results from what kind of test would rule out a diagnosis?

SnNOUT

-negative result on a sensitivity test (low false negative) rules out a diagnosis

10

Describe what a likelihood ratio is

LR is one test result for two populations

ex] LR of 11 means that the test results are 11 times more likely in a patient with the disease than in a patient without the disease

11

Describe how to get from pretest probability to posttest probability

Pretest odds = (pretest probability) / (1- pretest probability)

Pretest odds x LR = post test odds

Post test probability = (posttest odds) / (posttest odds + 1)