Recent studies of D-dimer as a “rule-out” test for deep venous thrombosis (DVT) frequently have used duplex ultrasound rather than venography as the gold standard. Because duplex ultrasound has limited ability to image the calf veins, there is potential for ultrasound studies to classify patients with calf DVT as...

This is the second of two articles focusing on the reference interval, the most widely used tool for interpretation of patient test results.  The first [1] was an introduction to the theoretical concepts that underpin the significance, construction and use of reference intervals. Here consideration is given to the...

Definite diagnosis of infection requires microbiological documentation; however, the identification of a specific etiology is frequently missing. In addition, bacterial cultures require at least 24-48 hours for a final result, which is too long for a decision to start antibiotics. Currently, the evaluation of the...

The population-based reference interval is the most widely used tool for interpretation of individual patient laboratory test results. The clinical value of those results depend crucially on the reference intervals with which they are compared, and all efforts directed at ensuring analytically precise and accurate...

Updated with new information from a 2008 article! Health demands that despite quite significant variation in its rate of production, the amount of carbon dioxide in blood is maintained within well-defined narrow limits. The homeostatic mechanisms that maintain the normal content of carbon dioxide in blood are...

All clinical procedures and treatments are associated with potential adverse effects of greater or lesser significance.  The undisputed value of blood testing for both diagnosis and monitoring of disease is tempered by the recognition that repeated blood sampling can result in blood loss of sufficient magnitude to...

With the use of a new Data Management System (DMS) software program [1], the majority of Point Of Care Testing (POCT) equipment throughout the Waikato District Health Board region has been connected to the Laboratory Information System (LIS) and the Hospital Information System (HIS). Prior to the new DMS, viewing...

The ‘gold standard’ sample for blood gas analysis is arterial blood obtained via an indwelling arterial catheter or by arterial puncture. For a number of reasons capillary blood is an attractive substitute sample that is routinely used in some clinical settings.  The purpose of this article is to examine the evidence ...

There are few medical diagnoses that depend solely on the result of a single blood test, but diabetes mellitus, which is defined by concentration of circulating glucose, is one that does. Quite apart from its long established role in diagnosis as well as life-long monitoring of diabetes, measurement of circulating...

Modern analytical devices for testing biological fluids, such as blood, have now developed a sophistication that ensures the quality of the analytical result is capable of matching that achieved in the central laboratory.    Complementary developments are focused on reducing operator-related and connectivity-related...