SPI Module 8 QA

Question 1

The routine, periodic evaluation of the US system is termed:

1. preventive maintenance
2. quantity assurance
3. quality insurance
4. quality assurance

Answer 1

4

Question 2

The middle rod group of the AIUM phantom scanned from the top measures the:

1. axial resolution
2. depth calibration accuracy
3. lateral resolution
4. sensitivity

Answer 2

1

Question 3

__________ evaluated by using the side surface of the object and scanning the same rod group used for axial resolution.

Answer 3

lateral resolution

Question 4

vertical and horizontal accuracy of the electronic calipers. calibration accuracy is performed by scanning the vertical and horizontal equidistant rods from the top.

Answer 4

range accuracy

Question 5

The testing device composed of a series of 0.75mm diameter stainless steel rods arranged in groups suspended in fluid is the:

1. AIUM 100 mm test object
2. string phantom
3. tissue phantom
4. Doppler tissue phantom

Answer 5

1

Question 6

The measure of the weakest echo signal that can be visualized on the image is called:

1. contrast resolution
2. dead zone
3. sensitivity
4. speckle

Answer 6

3

*system sensitivity is a measure of the weakest echo signal that can be visualized on the image. This is determined by the gain setting, with n TGC, at which a particular rod produces an echo. The bottom rod of the group of six vertical equidistant rods is typically used.

Question 7

The region where no imaging can take place is called the:

1. contrast zone
2. dead zone
3. sensitivity zone
4. shadow zone

Answer 7

2

Question 8

Statistical analysis is used to:

1. fins out if the result of the phantom testing is accurate
2. fins out if the results of the test object is accurate
3. find out if the results of their clinical testing is accurate
4. find out if the results of their academic testing is accurate

Answer 8

2

Question 9

To perform statistical analysis a Chi square is used, this incorporates:

1. the comparison test vs the Gold standard
2. the comparison test vs only positive findings
3. the comparison test vs only negative findings
4. the Gold standard vs only positive findings

Answer 9

1

*Chi square = comparison test vs Gold standard

Question 10

The term “true positive” means:

1. the test said there was no disease when there was
2. the test said there was no disease when there wasn’t
3. the test said there was disease when there was
4. the test said there was disease when there wasn’t

Answer 10

3

Question 11

Comparison test is incorrect; does not match the gold standard; the test says there is disease when there isn’t

Answer 11

FP: false positive

Question 12

comparison is correct; the test matches the gold standard; both are negative for disease

Answer 12

TN: true negative

Question 13

Comparison test is incorrect; does not match the gold standard; the test says there is no disease when there is.

Answer 13

FN: false negative

Question 14

The following information is needed to find the positive predictive value:

1. all of the positive
2. all of the negatives
3. both the positives and negatives
4. only the true positives and true negatives

Answer 14

1

*Negative/Positive Predictive value: prevalence of disease

PPV (Positive Predictive Value) - measures how often the test is correct when positive for disease (only includes the positive parameters)

PPV = TP/(TP+FP)

Question 15

_______ measures the percentage of examinations that correlated or matched with the gold standard

Answer 15

accuracy

*Accuracy = (TP)+(TN)/(TP)+(FN)+(TN)+(FP)

*accuracy falls between the sensitivity and specificity values and PPV and NPV

Question 16

What statistics findings is defined as “”the ability of a test to detect the absence of disease”?

1. accuracy
2. specificity
3. sensitivity
4. positive predictive value

Answer 16

2

*sensitivity: ability of a test to detect disease = TP/(TP + FN)

*specificity: ability of a test to detect the absence of disease = TN/(TN + FP)