Quality Control & Assurance Flashcards

Which statistical term describes the closeness of repeated measurements to each other, regardless of their proximity to the true value?

Answer: Precision

Precision (reproducibility) refers to how closely repeated measurements agree with each other, independent of whether they reflect the true value.

A laboratory adopts a new automated stainer. Which initial QC step must be completed before using it for patient specimens?

Answer: Perform validation studies comparing results to the manual reference method

Before patient use, new instrumentation must be validated by demonstrating performance equivalence or superiority to the established reference method.

What does 'lot-to-lot' testing of a new reagent batch involve in a histology QC program?

Answer: Comparing results using old and new lots on identical control tissue to confirm equivalent performance

Lot-to-lot testing runs both old and new reagent lots on the same control tissue concurrently to ensure the new lot performs equivalently before the old one is exhausted.

Which QC measure helps detect carry-over contamination between cases during grossing in a histology laboratory?

Answer: Cleaning grossing tools and surfaces between each specimen

Cleaning instruments and surfaces between cases prevents tissue carry-over that could lead to diagnostic errors from contamination.

A PAS (Periodic Acid-Schiff) stain fails to highlight glycogen in the positive control liver section. After confirming periodic acid freshness, what should be checked next?

Answer: Schiff reagent activity

If periodic acid is fresh but PAS staining fails, the Schiff reagent may have lost its reactivity (bleached or old), preventing aldehyde-fuchsin binding.

Which term describes the process by which a laboratory verifies that a test method performs as claimed by the manufacturer before implementing it for clinical use?

Answer: Method validation

Method validation (or verification for FDA-cleared tests) confirms that the method meets manufacturer performance specifications in the laboratory's specific environment.

During a CAP inspection, the inspector reviews the temperature logs for the tissue processor and finds several days with no recorded temperatures. What is the correct classification of this finding?

Answer: Phase II (deficiency requiring corrective action)

Missing required temperature records constitute a Phase II deficiency, requiring a corrective action plan to be submitted to CAP within the specified timeframe.