Clinical Laboratory Techniques & Procedures Flashcards
7 cards from real CLT practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Clinical Laboratory Techniques & Procedures flashcards as text
Which quality control rule indicates a systematic error when two consecutive QC results fall more than 2 standard deviations in the same direction?
Answer: 2-2s rule
The 2-2s Westgard rule is triggered when two consecutive QC values exceed 2 SD on the same side of the mean, indicating systematic bias.
A urine specific gravity of 1.035 measured by refractometry would be best described as:
Answer: Hypersthenuric
Hypersthenuria refers to urine with a specific gravity above 1.030, indicating highly concentrated urine, which can occur in dehydration or ADH excess.
When calibrating a micropipette for accuracy verification, the preferred method is:
Answer: Gravimetric measurement of dispensed distilled water
Gravimetric verification weighs the dispensed water on an analytical balance; using the density of water at a known temperature converts mass to volume.
Which of the following is the primary reason for using a silica gel desiccant in reagent strip storage containers?
Answer: To maintain strip performance by absorbing moisture
Moisture degrades the chemical reagent pads on urinalysis strips; the desiccant absorbs ambient humidity to extend shelf life and preserve reactivity.
A technologist is performing an acid-fast stain (Ziehl-Neelsen). What is the role of the carbol fuchsin heating step?
Answer: It drives the dye into the waxy mycobacterial cell wall
Heat facilitates penetration of carbol fuchsin through the high-lipid mycobacterial cell wall; the dye is then retained after acid-alcohol decolorization.
When preparing a blood smear for a malaria parasite examination, the thick smear differs from the thin smear in that it:
Answer: Uses lysed red cells to concentrate parasites for detection
Thick smears lyse RBCs during staining, concentrating parasites for higher sensitivity, but RBC morphology is lost, making species ID difficult.
A linear regression QC study comparing a new analyzer to a reference method yields a slope of 1.08 and an intercept of -2.5 mg/dL. This result indicates:
Answer: Both proportional and constant errors are present
A slope ≠ 1.00 indicates proportional error, while an intercept ≠ 0 indicates constant error; both are present in this case.