Laboratory Quality Control and Management Flashcards
7 cards from real CMT practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Laboratory Quality Control and Management flashcards as text
What is the primary purpose of running quality control (QC) samples in a clinical laboratory?
Answer: To monitor the precision and accuracy of test results
QC samples are run to monitor the precision and accuracy of analytical processes and detect errors before patient results are reported.
Which Westgard rule is triggered when a single control value exceeds the mean ± 3 standard deviations, indicating a random error?
Answer: 1₃s rule
The 1₃s rule is a rejection rule triggered when one control observation exceeds the mean ± 3 SD, indicating a possible random error.
In laboratory quality management, what does 'accuracy' specifically refer to?
Answer: How close a measurement is to the true or accepted reference value
Accuracy refers to how closely a measured value agrees with the true or accepted reference value.
What does the coefficient of variation (CV) primarily assess in laboratory quality control?
Answer: Imprecision (random error) of an analytical method
The coefficient of variation (CV = SD/mean × 100%) is a measure of imprecision or random error expressed as a percentage of the mean.
Which federal agency administers and enforces CLIA regulations for clinical laboratory quality standards in the United States?
Answer: Centers for Medicare & Medicaid Services (CMS)
The Centers for Medicare & Medicaid Services (CMS) administers and enforces CLIA regulations that establish quality standards for clinical laboratories.
When a Westgard 2₂s rule is triggered (two consecutive controls exceed ±2 SD in the same direction), what type of error is most likely present?
Answer: Systematic error
The 2₂s rule, where two consecutive controls exceed ±2 SD in the same direction, is indicative of systematic error such as a shift or drift in the method.
What is the primary purpose of proficiency testing (PT) in clinical laboratories?
Answer: To compare a laboratory's performance with peer laboratories using unknown samples
Proficiency testing involves external agencies sending unknown samples to laboratories so their performance can be compared against peer laboratories and accepted values.