Practice Test Geeks(MLS) Medical Laboratory Scientist Practice Test
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Quality Assurance & Standards Flashcards

7 cards from real MLS practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 7 Quality Assurance & Standards flashcards as text

  1. A QC result exceeds 3 standard deviations from the mean. According to Westgard rules, this triggers which rule?

    Answer: 1-3s

    The 1-3s Westgard rule is a rejection rule triggered when a single control value exceeds ±3 SD from the mean, indicating probable error.

  2. Which of the following BEST describes 'total allowable error' (TEa)?

    Answer: The maximum permissible combination of bias and imprecision for an analyte

    TEa defines the maximum error a method can produce and still yield clinically acceptable results, incorporating both systematic bias and random imprecision.

  3. Carryover in analytical instruments refers to:

    Answer: Contamination of a sample by a previously analyzed high-concentration sample

    Carryover occurs when residual analyte from a high-concentration specimen contaminates a subsequent sample, falsely elevating its result.

  4. A laboratory's glucose method has a sigma value of 6. This indicates:

    Answer: The method performs near six sigma and needs minimal QC rules

    A sigma value of 6 indicates excellent analytical performance (TEa is 6 SD wide), allowing simplified QC protocols with fewer control measurements.

  5. In a laboratory quality system, which document describes the step-by-step process for performing a specific test?

    Answer: Standard operating procedure (SOP)

    A standard operating procedure (SOP) provides detailed, step-by-step instructions for performing a specific test, ensuring consistency and reproducibility.

  6. Which interference is MOST likely to cause falsely elevated hemoglobin results on a spectrophotometric analyzer?

    Answer: Lipemia

    Lipemia causes turbidity that scatters light and can falsely elevate absorbance readings at 540 nm used for hemoglobin measurement.

  7. The purpose of calibration verification in a clinical laboratory is to:

    Answer: Confirm the calibration remains valid across the reportable range

    Calibration verification uses materials spanning the AMR to confirm that existing calibration settings continue to produce accurate results over the full reportable range.