When it comes to sample integrity, the clock starts ticking as soon as the sample of interest leaves the body. To be able to accurately assess the presence and/or concentration of an intended measurand, all efforts must focus on retaining the quality and integrity of the sample.
The period between sample collection and arrival in the laboratory is called transport time. The goal for optimal sample integrity is to minimize the transport time as the clock continues to tick during the sample preparation phase prior to analysis. Prolonged blood sample transport time may result in false decreases in glucose. Delays in centrifugation will see continued specimen metabolism with possible false plasma increases of potassium and magnesium from red cell leakage.
