Medical Laboratory Technician Laboratory Operations and QC Questions and Answers

Question 1

An MLT reviewing a Levey-Jennings chart for a daily glucose control run notices that the last two consecutive data points are outside the +2 SD limit. Which Westgard rule has been violated?

Accepted Answer

2_2s

Answer

1_3s

Answer

R_4s

Answer

4_1s

Question 2

A phlebotomist collects specimens for coagulation studies (light blue top), a complete blood count (lavender top), and a chemistry panel (serum separator tube - SST). If the tubes are drawn in the order of SST, lavender, and then light blue, which test result will most likely be falsely elevated?

Accepted Answer

Prothrombin Time

Answer

Hemoglobin

Answer

Serum Potassium

Answer

Blood Glucose

Question 3

To find comprehensive information regarding the hazards, safe handling, and emergency procedures for a new chemical reagent, an MLT should primarily consult the:

Accepted Answer

Safety Data Sheet (SDS)

Answer

Laboratory's Standard Operating Procedure (SOP)

Answer

Annual CAP inspection checklist

Answer

Instrument operation manual

Question 4

A laboratory is validating the precision of a new assay. A control material is analyzed 20 times, yielding a mean value of 80 mg/dL and a standard deviation (SD) of 4 mg/dL. What is the coefficient of variation (CV)?

Accepted Answer

5.0%

Answer

2.0%

Answer

20.0%

Answer

0.5%

Question 5

Under the Clinical Laboratory Improvement Amendments (CLIA), which of the following is a key requirement for laboratories performing moderate and high-complexity testing but NOT for those performing only waived testing?

Accepted Answer

Successful participation in an external proficiency testing (PT) program.

Answer

Following the manufacturer's instructions for test performance.

Answer

Maintaining a log of all patient results.

Answer

Having a designated area for performing laboratory tests.

Question 6

A technologist notes that all patient and quality control results for an analyte measured by spectrophotometry are significantly and consistently low. After confirming that reagents and controls are acceptable, which of the following is the most probable cause for this systematic error?

Accepted Answer

The instrument lamp is aging and has low light output.

Answer

The sample concentration is too high.

Answer

Air bubbles are present in the cuvette.

Answer

The wrong cuvette type (e.g., plastic instead of quartz) was used.

An MLT reviewing a Levey-Jennings chart for a daily glucose control run notices that the last two consecutive data points are outside the +2 SD limit.Which Westgard rule has been violated?

An MLT reviewing a Levey-Jennings chart for a daily glucose control run notices that the last two consecutive data points are outside the +2 SD limit.
Which Westgard rule has been violated?