Medical Laboratory Technician Exam Medical Laboratory Technician Laboratory Operations and QC Questions and Answers 2

Question 1

A laboratory receives a proficiency testing sample that yields results outside the acceptable range. What is the appropriate first step?

Accepted Answer

Investigate the cause of the discrepancy before resuming patient testing

Answer

Report the result and continue testing patient samples

Answer

Discard the proficiency sample and request a new one

Answer

Adjust the instrument calibration to match the expected value

Question 2

Which document defines the step-by-step procedure for performing a specific laboratory test?

Accepted Answer

Standard operating procedure

Answer

Quality manual

Answer

Organizational chart

Answer

Safety data sheet

Question 3

What is the primary purpose of running a blank sample during analytical testing?

Accepted Answer

To detect contamination or background interference

Answer

To calibrate the instrument for the next patient sample

Answer

To verify the reagent lot number is correct

Answer

To satisfy proficiency testing requirements

Question 4

In a Westgard multirule QC system, a 2-2s violation occurs when which of the following is observed?

Accepted Answer

Two consecutive controls exceed 2 standard deviations on the same side of the mean

Answer

One control exceeds 2 standard deviations from the mean

Answer

Two consecutive controls exceed 2 standard deviations on opposite sides of the mean

Answer

The range between two controls exceeds 4 standard deviations

Question 5

Which type of error is best detected by analyzing a trend of control values that progressively shift in one direction over several days?

Accepted Answer

Systematic error

Answer

Random error

Answer

Pre-analytical error

Answer

Clerical error

Question 6

What is the minimum frequency for verifying the temperature of a laboratory refrigerator used to store reagents, according to standard laboratory practice?

Accepted Answer

Daily

Answer

Weekly

Answer

Monthly

Answer

Only when an out-of-range QC result occurs