Carryover Analysis

Carryover

“Carryover” in laboratory testing, is defined as “the contamination of a specimen by the previous one”. Carryover testing is performed to help to prove or disprove carryover from the sample probe in clinical laboratory testing.

"Errors due to carryover of analyte from a sample with a high level of analyte to a subsequent one with a low level is a potential problem with automated analyzers. Carryover is especially important with analytes such as hCG, TSH, and antibodies to HIV and the hepatitis viruses."

"Carryover may be studied by using two samples, one with a high concentration of analyte and one without detectable or low concentration of analyte.  The low level sample is placed in the first and third positions and the high level sample is placed in the second position. Carryover will cause the value of the third sample to be higher than the first. Percent carryover can be calculated by subtracting the value of the first sample from the value of the third sample, dividing by the first sample value, and multiplying by 100.  (3rd - 1st)/(1st x 100)."

Reference: clinlabnavigator.com

COLA VER 11.2

As part of the method validation, has the laboratory evaluated the potential risk of carryover between samples, and does the procedure include identification, investigation, and corrective action of errors due to carryover?