Evidence-based decision limits for cardiac troponin: Low-level elevation and prognosis

Evolution of diagnostic criteria for MI, using cardiac troponin. See text for details. Current recommendations are for a single decision limit at the 99^th percentile or, if there is not acceptable analytic precision at this concentration, at the level of the 10% CV. MMD, Minor myocardial damage.

Example of a troponin assay with a CV of 10% at 0.1 ng/mL. Analytic performance of each troponin assay is characterized by repeated measurements on the same sample. CV is a measure of the precision of the assay at a given concentration. If the CV were 20% instead of 10% at this concentration, 67% of values from the same sample would fall within the range of 0.08 to 0.12 ng/mL and 95% within the range of 0.06 to 0.14 ng/mL.