Chapter 29: Statistics

Question 1

the results of our exam indicate that the patient has disease

Answer 1

positive

Question 2

our exam results indicate that the patient has no disease

Answer 2

negative

Question 3

our exam is correct

Answer 3

true

Question 4

our exam is incorrect

Answer 4

false

Question 5

our test indicated disease and is correct

Answer 5

true positive

Question 6

our test indicates normal and is correct

Answer 6

true negative

Question 7

our test indicates disease and is incorrect

Answer 7

false positive

Question 8

our test indicates normal and is incorrect

Answer 8

false negative

Question 9

what determines if the test is positive or negative

Answer 9

our test (ultrasound/doppler)

Question 10

what determines if it is true or false?

Answer 10

the gold standard (angiography, CT, venography)

Question 11

what is the statistics rule?

Answer 11

look at our test first to determine + or - and then the gold standard to determine true or false

Question 12

the ability of a test to detect disease when present

Answer 12

sensitivity

Question 13

true positive/ true positive + false negative

Answer 13

sensitivity

Question 14

the ability of a test to identify normalcy (no disease present)

Answer 14

specificity

Question 15

true negative / true negative + false positive

Answer 15

specificity

Question 16

percentage of positive studies that are correct

Answer 16

positive predictive value

Question 17

true positive / true positive + false positive

Answer 17

positive predective value

Question 18

percentage of negative studies that are correct

Answer 18

negative predictive value

Question 19

true negative / true negative + false negative

Answer 19

negative predictive vale

Question 20

percentage of all studies that are correct

Answer 20

accuracy

Question 21

true positive + true negative / total number of exams

Answer 21

accuracy