SM Quality Assurance & Compliance 3 — Questions and Answers
Question 1: Under CLIA, which personnel category is authorized to perform high-complexity testing without additional supervision?
- Phlebotomist with 1 year experience
- Technician with an associate degree in health science
- Medical Laboratory Scientist (MLS) with ASCP certification (Correct answer)
- High school graduate with 6 months laboratory training
Correct answer: Medical Laboratory Scientist (MLS) with ASCP certification
An MLS (ASCP) meets the education and training requirements for performing high-complexity testing under CLIA regulations.
Question 2: What is the purpose of a delta check in clinical microbiology?
- Compare current result to previous result for the same patient to detect errors (Correct answer)
- Calculate the difference between two QC runs
- Verify that proficiency testing scores meet minimum thresholds
- Monitor the rate of contamination in blood cultures
Correct answer: Compare current result to previous result for the same patient to detect errors
Delta checks compare a patient's current result with a prior result to flag implausible changes that may indicate specimen mix-up or analytical error.
Question 3: A laboratory's urine culture contamination rate rises from 3% to 12% over one month. Which is the MOST likely source?
- Change in susceptibility testing panels
- Poor collection technique or patient instruction (Correct answer)
- Improper QC organism storage
- Autoclave malfunction
Correct answer: Poor collection technique or patient instruction
Rising contamination rates in urine cultures most commonly reflect inadequate patient education on midstream clean-catch collection technique.
Question 4: Which ISO standard is specifically designed for the quality management of medical laboratories?
- ISO 9001:2015
- ISO 15189:2022 (Correct answer)
- ISO 17025:2017
- ISO 13485:2016
Correct answer: ISO 15189:2022
ISO 15189 specifies quality management system requirements and competence requirements specifically for medical laboratories.
Question 5: Which of the following is an example of a pre-analytical error in microbiology?
- Misidentification of an organism on MALDI-TOF
- Reporting a Gram stain result before reading it
- Collecting a sputum specimen after the patient rinsed with mouthwash (Correct answer)
- Selecting the wrong antibiotic breakpoint table
Correct answer: Collecting a sputum specimen after the patient rinsed with mouthwash
Rinsing with mouthwash before sputum collection is a pre-analytical error that can reduce or eliminate oral pathogens and increase contaminating flora.
Question 6: CLSI breakpoints for antimicrobial susceptibility testing are updated periodically. What is the PRIMARY reason laboratories must adopt updated breakpoints promptly?
- To comply with billing requirements for susceptibility reports
- To ensure patient therapy decisions are based on current resistance definitions (Correct answer)
- To reduce the number of organisms requiring extended testing
- To qualify for reimbursement under Medicare Part B
Correct answer: To ensure patient therapy decisions are based on current resistance definitions
Updated breakpoints reflect current pharmacokinetic/pharmacodynamic data and resistance mechanisms, ensuring clinically accurate susceptibility interpretations for guiding therapy.
Question 7: A microbiology lab is implementing a new automated blood culture system. Which study design is MOST appropriate to validate the new system before replacing the current one?
- Retrospective chart review
- Parallel testing with split specimens (Correct answer)
- Proficiency testing comparison
- Case-control study
Correct answer: Parallel testing with split specimens
Parallel testing using split specimens from real patient samples allows direct comparison of the new and existing systems under identical conditions.
SM Quality Assurance & Compliance 3
Under CLIA, which personnel category is authorized to perform high-complexity testing without additional supervision?