PP Bioestadistics Flashcards
What is the Median?
Middle value
What is the mean?
Average
What is the Mode?
Most frequent value
What does sensitivity tell you?
People that have the disease with a (+) test
= A / (A+C)
= 1 - false negative rate
What does specificity tell you?
People that don’t have the disease with a (-) test
= D / ( D+B)
= 1 - false positive rate
What does PPV tell you?
Probability of having the disease with a (+) test
= A / ( A + B)
What does NPV tell you?
Probability of not having the disease with a (-) test
= D / (C+ D)
What does incidence tell you?
Number of new cases in a period of time
What does prevalence tell you?
Total of cases
What does OR tell you?
Diseased are x time more likely to see risk factor
What does Confidence interval = 96% tell you?
95% sure it lies within the interval
What does RR tell you?
Risk of getting the disease with known exposure
What is NNT?
NNT to change 1 life
What does a p value < 0.5 tell you?
Random chance that you will be wrong 1 time out of 20
What does a Null hypothesis tell you?
Nothing’s happening
What does Pawer tell you?
Probability of detecting a < > when there is one
P= (1- beta)
What is Type I error?
False positives
Admitting there is a < > when there is not
Alfa = probability of making a TI error
What is Type II error?
False negative
Denying there is a < > when there is one
Beta = probability of making a TII error
What is Accuracy?
Validity “truth”