Chapter 34: Quality Assurance

Question 1

the overall percentage of correct results

Answer 1

accuracy

Question 2

a well-established and reliable testing parameter, which, for vascular disease, is often angiography

Answer 2

gold standard

Question 3

the evaluation of one’s work by other experts in the same field

Answer 3

peer review

Question 4

it is the ability of a test to detect disease

Answer 4

sensitivity

Question 5

it is the ability of a test to correctly identify a normal result

Answer 5

specificity

Question 6

a program for the systematic monitoring and evaluation of the various aspects of vascular testing to ensure that standards of quality are met

Answer 6

quality assurance

Question 7

making effective use of numerical data relating to groups of individuals or experiments

Answer 7

statistics

Question 8

compare one form of a diagnostic test with another that is well-established, reliable, and considered reference standard

Answer 8

“gold standard”

Question 9

assumed to be the truth

Answer 9

“gold standard”

Question 10

number of studies performed which state disease is present and gold standard agrees

Answer 10

true positives

Question 11

number of negative findings reported that were also reported negative by gold standard

Answer 11

true negatives

Question 12

studies that are reported positive but found to be negative by the gold standard

Answer 12

false positives

Question 13

states that a study is normal when gold standard identifies disease

Answer 13

false negatives

Question 14

the degree of “closeness” something is to its actual value

Answer 14

accuracy

Question 15

percentage of correct results

Answer 15

accuracy

Question 16

calculated as total number of correct tests divided by the total number of all tests

Answer 16

accuracy

Question 17

measures the proportion of actual positives studies correctly identified

Answer 17

sensitivity

Question 18

ability to identify disease when disease is present

Answer 18

sensitivity

Question 19

calculated by taking TP results and dividing by all positive results determined by gold standard

Answer 19

sensitivity

Question 20

ability of a test to identify something as normal or the absence of disease

Answer 20

specificity

Question 21

calculated by dividing the number of TN results by all the negative results as identified by gold standard

Answer 21

specificity

Question 22

consistency of obtaining similiar results in similar circumstances

Answer 22

reliability

Question 23

accuracy over a period of time

Answer 23

reliability

Question 24

proportion of patients with positive test results that are correctly identified

Answer 24

positive predictive value

Question 25

provides probability that positive test reflects underlying disease for which the test is being conducted

Answer 25

positive predictive value

Question 26

calculated at the number of TP studies divided by all the positive studies

Answer 26

positive predictive value

Question 27

The proportion of negative test results when there is no underlying disease present

Answer 27

negative predictive value

Question 28

provides probability that a negative test reflects absence of diseaes

Answer 28

negative predictive value

Question 29

statistical test, that in sum, compares the difference between what one "expects" and what one actually "observes"

Answer 29

the chi-square test

Question 30

the more test that are performed that agree with the "gold standard" or the narrower the difference between what is expected and what is observed, the greater the accuracy

Answer 30

the chi-square test

Question 31

table containing four letters (A, B, C, and D); each letter represents the results of what was expected and what was observed

Answer 31

the chi-square test

Question 32

duplex ultrasound is what was ______

Answer 32

expected

Question 33

angiogram is what was _____

Answer 33

observed

Question 34

offers a well established alternative method of QA

Answer 34

Peer review

Question 35

specific quality indicators for peer review

Answer 35

test appropriateness adherence to criteria technical quality adherence to protocol completeness timeliness

Question 36

______ values are an integral part of a QA program.

Answer 36

statistical

Question 37

In vascular testing, what is typically considered to be the gold standard?

Answer 37

angiography

Question 38

What is the identification of a 50% - 70% stenosis of the internal carotid artery and a 60% stenosis by angiography an example of?

Answer 38

true positive

Question 39

Upon ultrasound evaluation, DVT is found in the popliteal vein; venography demonstrates a widely patent vessel. What is this an example of

Answer 39

false positive

Question 40

During duplex assessment of the abdominal aorta, the aorta measures less than 2.0 cm, which is confirmed by angiography. What is this an example of?

Answer 40

true negative

Question 41

Duplex evaluation of the superior mesenteric artery demonstrated velocities of 150 cm/s. Angiography demonstrated a 70% stenosis in the same vessel. What is this an example of?

Answer 41

false negative

Question 42

Which of the following is NOT likely to occur if false-positive results are indicated by the duplex ultrasound examination? a. unnecessary treatment b. lack of treatment when treatment is needed c. unnecessary stress to the patient d. repeat examination

Answer 42

a

Question 43

Which of the following would have the highest accuracy? a. 25 true positives and 30 true negatives out of 100 examinations b. 20 true positives and 10 true negatives out of 100 examinations c. 50 true positives and 5 true negatives out of 100 examinations d. 10 true positives and 75 true negatives out of 100 examinations

Answer 43

d

Question 44

An increase in which of the following results would increase the sensitivity of an examination? a. false positive b. false negative c. true positive d. true negative

Answer 44

c

Question 45

Which results are needed to improve specificity? a. true negatives b. true positives c. false negatives d. false positives

Answer 45

a

Question 46

What is the consistency of obtaining similar results under similar circumstances?

Answer 46

reliability

Question 47

Which of the following would an increase in the number of false-positive results have impact on? a. positive predictive value and negative predictive value b. positive predictive value and specificity c. negative predictive value and sensitivity d. positive predictive value and sensitivity

Answer 47

b

Question 48

After statistical analysis, a test was found to have a sensitivity of 92% and a specificity of 84%. Which of the following could represent the overall accuracy? a. 95% b. 82% c. 89% d. cannot be determined

Answer 48

c

Question 49

If a test has a negative predictive value of 50%, how sure can you be that your test results is negative?

Answer 49

equivocal

Question 50

In general, if the sensitivity of a test increases, what will happen to the specificity of the test?

Answer 50

decreasese

Question 51

Which of the following parameters would an increase in the number of false-negative results impact? a. negative predictive value and sensitivity b. positive predictive value and sensitivity c. sensitivity and specificity d. negative predictive value and specificity

Answer 51

a

Question 52

_________ refers to a program for the systematic monitoring and evaluation of the various aspects of vascular testing to ensure that standards of quality are being met.

Answer 52

quality assurance

Question 53

_______ is the science of making effective use of numerical data relating to groups of individuals or experiments

Answer 53

statistics

Question 54

A(n) ______ is used to compare one form of a newer diagnostic test with another that is well established and reliable.

Answer 54

gold standard

Question 55

_______ are the number of studies performed by ultrasound, which state that disease is present and the gold standard agrees with the ultrasound findings.

Answer 55

true positives

Question 56

_______ are the number of studies performed by ultrasound, which state that disease is not present and are also reported as negative by the gold standard.

Answer 56

true negatives

Question 57

Studies that are reported positive by ultrasound but are found to be negative by the gold standard are known as

Answer 57

false positives

Question 58

If a study is normal on ultrasound but the gold standard identifies disease, it is an example of a(n) _____

Answer 58

false negative

Question 59

Accuracy is calculated as ______ number of correct tests _____ by the total number of all tests.

Answer 59

total divided

Question 60

_____ is calculated by taking the true positive results and dividing these by all positive results as determined by the gold standard

Answer 60

sensitivity

Question 61

Dividing the number of true negatives by all the negative results as identified by the gold standard results in the ______ of the test.

Answer 61

specificity

Question 62

A vascular laboratory that has an overall accuracy of 96% over an average of 5 years would be said to be ______

Answer 62

reliable

Question 63

_______ is calculated as the number of true positives divided by all the positive studies

Answer 63

positive predictive values

Question 64

True negatives divided by all studies determined to be negative results in the _______

Answer 64

negative predictive value

Question 65

In a chi-square analysis, boxes A and B are used to determine ______, whereas boxes C and D are used to determine ____.

Answer 65

positive predictive value negative predictive value

Question 66

In a chi-square analysis, boxes A and C are used to determine ______, whereas boxes B and D are used to determine _____.

Answer 66

sensitivity specificity