Deck 16: Quality Assurance and Quality Control in the Molecular Laboratory

Question 1

Which test method is best for a fixed tissue specimen?

A) Long-range PCR
B) Southern blot
C) Standard PCR
D) PFGE

Answer 1

Standard PCR

Question 2

The ability of a molecular-based assay to detect only the analyte and not other targets is called which of the following?

A) Clinical specificity
B) Clinical sensitivity
C) Analytic sensitivity
D) Analytic specificity

Answer 2

Analytic specificity

Question 3

Which is used to calibrate an instrument that measures analyte in saline?

A) An unknown patient sample diluted in saline
B) A reference standard diluted in saline
C) A positive control diluted in water
D) A reference standard diluted in water

Answer 3

A reference standard diluted in saline

Question 4

An unlabeled bottle of clear liquid is found on a shelf. A sign on the shelf says, "Tris-EDTA Buffer, pH 8.0." What is the proper course of action?

A) Use the liquid as Tris-EDTA.
B) Taste the liquid to make sure it isn't saline.
C) Dispose of the liquid.
D) Measure the pH. If it is 8.0, proceed to use the liquid as Tris-EDTA.

Question 5

Which of the following controls defines the lower limit of reproducible and accurate detection of a molecular target?

A) Positive
B) Negative
C) Sensitivity
D) Amplification

Question 6

The delivery of accurate voltage and current by an electrophoresis power supply should be checked how often?

A) Daily
B) Weekly
C) Monthly
D) Yearly

Question 7

Which of the following organizations has established standards used by laboratory professionals when developing, implementing, and performing molecular-based laboratory tests?

A) Clinical and Laboratory Standards Institute
B) American Society for Clinical Laboratory Science
C) Joint Commission on Accreditation of Healthcare Organizations
D) National Accrediting Agency for Clinical Laboratory Science

Question 8

A blood sample is received in the laboratory for factor V Leiden analysis. What precautions are appropriate?

A) No precautions
B) Transmission-based precautions
C) Standard precautions
D) Contact precautions

Question 9

A blood specimen is received in the laboratory for a PCR assay to detect cytomegalovirus (a DNA virus) on a Wednesday night. The PCR assay will not be performed until the next Monday morning. How should this specimen be stored to maintain the integrity of the nucleic acid prior to analysis?

A) Lyze RBCs, centrifuge, and store at 22^oC
B) Lyze RBCs, centrifuge, and store at -20^o
C) Whole blood stored at 22^o-25^oC
D) Whole blood stored at 35^o-37^oC

Question 10

A technologist in a tissue bank who performed HLA typing by DNA analysis was asked to bank all DNA extracted from specimens received in the laboratory so as to maintain the nucleic acid for the longest period in the most limited space. How should the DNA be stored to satisfy this request?

A) Freeze-dried at 22^o-25^oC
B) DNase-free water at 22^o-25^oC
C) TE buffer at 2^o-8^oC
D) DNase-free water at -70^oC

Question 11

An assay that detects an analyte associated with a particular disease only in patients who have that disease and not in patients who do not have the disease has which of the following?

A) Analytic specificity
B) Analytic sensitivity
C) Clinical specificity
D) Clinical sensitivity

Question 12

A lavender-top tube labeled "John Smith" is received in the molecular biology laboratory. The tube is attached to a requisition stamped "John Doe," with today's date, requesting testing for t(9:22). Which of the following describes the proper course of action for the technologist who receives this specimen?

A) Perform the test as requested, and report the results for John Doe.
B) Change the labeling on the requisition to match that of the tube, and perform the test.
C) Notify the laboratory supervisor.
D) Call the nursing unit to ask whether John Doe or John Smith is correct, and make the change.

Question 13

An unlabeled specimen arrives in the laboratory with an accompanying requisition. The requisition is properly filled out. How should you proceed?

A) Proceed with testing.
B) Do not proceed with the test and notify the supervisor.
C) Cancel the test and discard the tube.
D) Label the specimen yourself and proceed with the test.

Question 14

A quantitative method was performed 100 times, and results from 99 of the 100 runs were in agreement with each other. This method has 99%:

A) Precision
B) Specificity
C) Sensitivity
D) Accuracy

Question 15

What is required for incorporating an FDA-approved test into a laboratory?

A) Proceed to use the test reagents according to the manufacturer's directions.
B) Validate test performance on reference and validation specimens.
C) Use the test, substituting reagents previously validated in the laboratory.
D) Request and review quality-assurance data from the manufacturer.

Question 16

An outbreak of Salmonella has occurred in the community. Molecular-based assays will be performed to determine if multiple isolates of Salmonella taken at hospital X are related to each other and part of the outbreak. Laboratory technologists have accumulated 10 different cultures growing Salmonella and suspect that there may be more isolated in the next few days. How should these organisms be handled until the molecular-based assays can be performed in about 3 days?

A) Maintain organisms in culture growing on solid agar in an incubator 35^o-37^oC.
B) Freeze suspensions of the organisms at -20^oC.
C) Isolate DNA from all organisms and store at -20^oC.
D) Isolate DNA from all organisms and store at 22^o-25^oC.

Question 17

Which of the following organizations provides oversight and governs the use the radioactive materials in the clinical laboratory?

A) National Fire Protection Association
B) Nuclear Regulatory Commission
C) Clinical Laboratory Improvement Amendments
D) American Society for Clinical Laboratory Science

Question 18

Whole blood was sent to the laboratory for viral load determination of HIV (an RNA virus). It was received on a Saturday morning, and the technologist working in the receiving section of the laboratory put the tube in the refrigerator at 2^o-8^oC. The molecular technologist came on Monday morning and collected the specimens that had been sent to the laboratory over the weekend. What will likely be required on Monday morning?

A) RNA isolation and viral load testing as requested
B) Request for blood redraw
C) HIV antibodies testing after forwarding the tube to the serology laboratory
D) Transfer of the blood into a tube containing guanidine isothiocyanate

Question 19

Which of the following controls can distinguish between a true negative in a nucleic acid amplification assay from a false negative in which amplification failed in the specimen?

A) Positive
B) Negative
C) Sensitivity
D) Amplification

Question 20

The temperature in a refrigerator that is used to store patient specimens and reagents should be checked how often?

A) Hourly
B) Daily
C) Biweekly
D) Weekly

Question 21

Which of the following does not have to be documented in a procedure description that is written according to CLSI guidelines?

A) Sequence of primers
B) Credentials of technologist performing the assay
C) Acceptable ranges of product sizes
D) Probe purification conditions

Question 22

What is the proper way to handle raw data from a completed test run?

A) Submit the data to the ordering physician.
B) Discard the data immediately after the case is signed out.
C) Immediately shred the data to maintain patient privacy.
D) Retain the data with the final reports of the test run.

Question 23

Controls run in a capillary gel electrophoresis instrument have been consistently unacceptable. Low signal strength is evidence that the laser is not functioning properly. Which of the following is the correct course of action for the technologist in charge of this piece of equipment?

A) Call the manufacturer, ask that a replacement laser be shipped, remove the old laser, and insert the new laser when it arrives.
B) Scan eBay for a compatible laser, purchase the laser, and replace the old laser with the newly purchased laser.
C) Request a service visit from the manufacturer's technical support team who can safely replace the old laser with a new laser.
D) Tag the instrument for removal and disposal, and order a new instrument from the manufacturer.

Question 24

The analysis of external specimens to assess technologist competency and assay performance is which kind of testing?

A) Proficiency
B) Quality control
C) Quality assurance
D) Competency

Question 25

Which is not intended for diagnostic use?

A) IVD reagents
B) RUO test kits
C) FDA-approved test kits
D) FDA-cleared reagent sets

Question 26

Probes, primers, antibodies, and other test components that detect a specific target, such as a cell surface protein or DNA mutation, without claims to clinical significance are classified as what type of reagents?

A) FDA cleared
B) IVD
C) RUO
D) ASR

Question 27

A woman calls and asks that the results of her husband's HIV viral load assay be faxed to her. She gives the technologist her husband's name and medical record number along with the date the specimen was collected and her fax number. She states that she is calling for her husband and has his approval. Which of the following is the correct course of action for the technologist?

A) Fax the results as requested.
B) Tell the woman that her husband can get his test results from his physician.
C) Contact the husband to verify that this request is acceptable with him.
D) Report the results by telephone.

Question 28

Which is the proper way to report a threonine-to-methionine mutation at amino acid position 790?

A) 790 T>M
B) M790T
C) T790M
D) TM790

Question 29

A battery-operated pipetting device has stopped working. Which of the following describes the first course of action for the technologist using this pipet?

A) Discard the pipet, and order a new one.
B) Call the manufacturer to request that a technical support representative make a service call.
C) Change or charge the batteries.
D) Put the pipet back in the drawer and get a new one.

Question 30

A fax report of patient results is received in error. What should be done?

A) Call the sender immediately.
B) File the report with quality-assurance documents.
C) Discard the report in a standard waste receptacle.
D) Read the report to others in the laboratory.