Medical Laboratory Technician Exam Laboratory Operations and Safety 2

Question 1

In a Levey-Jennings chart, which Westgard rule flags a run when one control value exceeds the mean by more than 3 standard deviations?

Accepted Answer

1-3s

Answer

The 1-3s Westgard rule is a rejection rule triggered when a single control measurement exceeds ±3 SD from the mean.

Question 2

Which type of error causes all quality control results to shift in the same direction over time?

Accepted Answer

Systematic error

Answer

Systematic error produces a consistent directional shift or trend in QC values and is often caused by reagent deterioration or calibration drift.

Question 3

A laboratory's proficiency testing (PT) result for glucose is graded as unacceptable. What is the required next step under CLIA?

Accepted Answer

Perform an investigation and implement corrective action

Answer

CLIA requires laboratories to investigate the cause of an unacceptable PT result and document corrective actions taken.

Question 4

Which type of pipette delivers its nominal volume from tip drainage and is identified by a frosted or etched band near the top?

Accepted Answer

TD (to deliver) pipette

Answer

TD (to deliver) pipettes are calibrated so that the volume drains out and the frosted band indicates no rinsing is needed to deliver the full volume.

Question 5

What is the purpose of a delta check in the laboratory?

Accepted Answer

To compare a patient's current result to a previous result

Answer

A delta check compares a patient's current laboratory result to their prior result to detect specimen identification errors or unexpected clinical changes.

Medical Laboratory Technician Exam Practice Test

Medical Laboratory Technician Exam Practice Test

Medical Laboratory Technician Exam Laboratory Operations and Safety 2