USCIS Quality Control & Assurance 4

Question 1

A lab technician performing gonorrhea NAAT testing for I-693 applicants notices the internal amplification control failed on three of ten samples. What is the most appropriate action?

Accepted Answer

Repeat testing on those three samples; failed internal controls indicate inhibition or assay failure

Answer

A failed internal amplification control signals possible PCR inhibition or assay failure, requiring repeat testing of those specific samples.

Question 2

What is the purpose of delta checks in a clinical laboratory performing I-693 tests?

Accepted Answer

To compare a patient's current result with their previous result to detect specimen mix-ups or abrupt changes

Answer

Delta checks flag significant changes from prior results for the same patient, helping identify specimen errors or clinically important changes.

Question 3

A clinic administers the MMR vaccine to an I-693 applicant but cannot locate the VFC (Vaccines for Children) temperature log for the previous weekend. What is the required quality assurance action?

Accepted Answer

Document the missing monitoring period, investigate if vaccines were compromised, and report to the VFC program coordinator

Answer

Missing temperature logs must be documented, investigated, and reported to the VFC coordinator to determine if vaccines remain viable.

Question 4

Which of the following best describes the difference between quality control (QC) and quality assurance (QA) in an I-693 examination setting?

Accepted Answer

QC monitors test accuracy in real time; QA is a broader system-wide review of all processes affecting test quality

Answer

QC refers to real-time monitoring of test performance, while QA encompasses all policies and procedures ensuring overall quality throughout the examination process.

Question 5

A syphilis RPR test is reported as reactive with a titer of 1:32. The confirmatory treponemal test (e.g., TP-PA) is non-reactive. What is the most likely quality assurance concern?

Accepted Answer

Specimen mix-up or prozone effect should be investigated before reporting results

Answer

A discordant RPR/treponemal pattern may indicate prozone effect (very high antibody titers blocking agglutination) or specimen mix-up, requiring investigation.

USCIS - Medical Exam Practice Test

USCIS - Medical Exam Practice Test

USCIS Quality Control & Assurance 4