Why is the time of collection critical for certain tests, and give two examples of such tests?

Prepare for the CAMLPR Specimen Collection Competency Test. Practice with diverse question sets including multiple-choice and flashcards. Each question includes hints and explanations to help you become proficient before the exam.

Timing in specimen collection matters because some substances change quickly once the sample leaves the body. Ammonia and lactate are classic examples: if blood is not processed right away or kept cold on ice, ammonia can rise and lactate can accumulate, giving falsely high results. That’s why immediate processing or cooling is needed to preserve the true in-body concentrations.

Fasting glucose illustrates another timing-related requirement: the patient’s state before collection matters. The test is intended to reflect baseline glucose when the person hasn’t eaten for a set period, so a fasting period is required to avoid post-meal elevations skewing the result. Together, these examples show how both rapid post-collection changes and pre-collection conditions affect accuracy.