Which of these is not a random laboratory error?

Which of these is not a random laboratory error?

• A. Variation in glassware
• B. Electronic or optical inconsistency
• C. Contamination
• D. Anisocytosis

Answer: (D)

Anisocytosis is not a random lab error because it represents a genuine biological variation in red blood cell size, not a flaw or inconsistency in the laboratory process. Random errors come from the measurement system or handling, such as differences in glassware causing variable volumes, instrument readouts that fluctuate (electronic or optical inconsistency), or contamination introducing unintended material. Anisocytosis, instead, reflects the patient’s physiology or pathology (e.g., anemia) and would be observed on a blood smear or CBC as true variability in cell size, not as a result of lab technique.

Anisocytosis is not a random lab error because it represents a genuine biological variation in red blood cell size, not a flaw or inconsistency in the laboratory process. Random errors come from the measurement system or handling, such as differences in glassware causing variable volumes, instrument readouts that fluctuate (electronic or optical inconsistency), or contamination introducing unintended material. Anisocytosis, instead, reflects the patient’s physiology or pathology (e.g., anemia) and would be observed on a blood smear or CBC as true variability in cell size, not as a result of lab technique.