This article demonstrates that adding a lot of patients without disease and with low test results to a study may improve the ROC curve significantly without any improvement in sensitivity or in positive predictive value of the parameter evaluated. The precision-recall curves are not impacted by the addition of...

Procalcitonin (PCT) is a biomarker which is elevated in bacterial infection. Usefulness of PCT measurements in community-acquired pneumonia (CAP) has to be proven by many studies. A single measurement of PCT on admission or outpatient visits is useful to diagnose CAP, estimate causative pathogens pattern, and for...

Bacterial infections are one of the major reasons for patients presenting to the ED - and the main cause of death in elderly patients. It is important to identify elderly patients with bacterial infections early and initiate treatment in the ED for a better outcome. However, an infection in an elderly patient can be...

For patients presenting to the ED with symptoms of a suspected infection, measuring procalcitonin (PCT) is a useful diagnostic tool to identify bacterial infections, such as sepsis, allowing for early initiation of proper antibiotic treatment. In assessing the severity of sepsis, serum PCT levels are an important...

This first of two articles on method comparison studies gives some key concepts related to the design of the method comparison study, data analysis and graphical presentation, stressing the importance of a well-designed and carefully planned experiment using adequate statistical procedures for data analysis when...

When a new D-dimer method is evaluated, it’s typically compared to an established D-dimer method using both an analytical and a clinical comparison. Analytical comparisons should be discouraged, as they do not give any useful information about the potential clinical usability of the assay. D-dimer assay comparisons...

Point-of-care testing (POCT) covers a broad range of pathology and non-pathology testing. The volume of POCT is rapidly increasing with an annual growth rate of 12-15 %. By virtue of its compactness, portability, and the feasibility of operation by non-laboratory personnel, where fast and accurate testing methods and...

Clinical sensitivity, clinical specificity and predictive values are frequently used as performance measure for a biochemistry assay. When D-dimer assay performance is presented, emphasis is often on the negative predictive value (NPV). However, predictive values are greatly influenced by the prevalence of the...

With the ultimate goal of improving patient care, adoption of point-of-care testing (POCT) continues to grow at a high rate. The ability to deliver fast and reliable results near the patient is a key driver for improving patient outcomes and optimizing clinical workflow. While there are many advantages, controlling...

Reprinted from Ann Lab Med 2014 Sep; 34(4):263-73. Procalcitonin (PCT) is used as a biomarker for the diagnosis of sepsis, severe sepsis and septic shock. At the same time, PCT has also been used to guide antibiotic therapy. This review outlines the main indications for PCT measurement and points out possible...