How Often Must the Partial Thromboplastin Time (PTT) Reference Interval

question 2

Multiple Choice

How often must the partial thromboplastin time (PTT) reference interval be determined?

• A) Only when both the normal and abnormal controls are outside their acceptable limits
• B) At least every 6 months
• C) With each new lot of reagent
• D) Only when the normal control is outside its acceptable limits

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Definitions:

Urination

The process of excreting urine from the urinary bladder through the urethra to the external urinary orifice, regulated by voluntary and involuntary muscle controls.

Erection

The process by which erectile tissue becomes enlarged and firm, typically in response to sexual excitement.

Vertebral Spinous

Referring to the spinous process, which is a bony projection off the posterior (back) part of each vertebra in the spine, serving for muscle attachment and leverage.

Erector Spinae

A group of muscles running vertically up the back that maintain posture and help in the movement of the vertebral column.