Table 1. Characteristics of an ideal biomarker of infection.

Criteria	Characteristic
Analytic validation	Routinely accessible
	Rapid availability (short turn-around time)
	Reproducible
	Accurate
	Cost-effectiveness
Qualification	Good sensitivity and specificity
	High predictive values
	Good correlation to severity of presentation and/or organ dysfunction and/or source control and/or antibiotic therapy
	Predictor of mortality
Utilization	Easily interpreted
	Objective
	Dynamic/rapid kinetics
	Kinetics independent of organ dysfunction and other concomitant therapies (ex. steroids)
	Non or minimally invasive
	Continuous variable