Laboratory tests represent a high-volume medical procedure that is paramount for everyday clinical decision-making. Thousands of different types of in vitro diagnostic (IVD) devices are sold around the globe in order to facilitate these tests. However, studies indicate that these devices are often applied inappropriately, with tests being both under- and over-utilised, depending on the clinical scenario.
In vitro diagnostic devices
While under-utilisation of tests can lead to delayed patient diagnosis and increased morbidity, over-utilisation of tests can result in unnecessary sample collection procedures as well as increased costs and a greater risk of false positives.
The extent of the financial burden created by over-utilisation of laboratory tests is not known, with liberal ordering practices existing in a number of different IVD markets including cardiac marker tests, haematology tests, hemostasis tests and thyroid function tests (TFTs).
For example, TFTs represent commonly utilised devices that are ordered in very high volumes. Thyroid disease is the second most common endocrine disease after diabetes and encapsulates a number of conditions, including hyperthyroidism and hypothyroidism. Clinical symptoms of thyroid disease can vary substantially between patients and are often not specific, meaning these conditions tend to be diagnosed using biochemical assays. These heterogeneous symptoms, combined with a lack of clear testing guidelines, mean that the decision of whether or not to order TFTs is often left to a physician’s personal clinical judgement.
Over-testing is also a recognised issue in the haematology and hemostasis test markets and is likely bolstering current sale volumes. The complete blood count (CBC) represents one of the most commonly ordered IVD tests. However, numerous academic reports and physician society guidelines now recommend against ordering of routine CBCs prior to low-risk surgeries, and it has been suggested that repetitive CBCs in stable patients can cause phlebotomy-related anaemia.
Similarly, pre-operative coagulation tests are still ordered in most countries and geographical regions, even though there is a growing consensus amongst physicians that, in this scenario, prothrombin time (PT) and activated partial thromboplastin time (aPTT) tests do not provide clinical benefit.
In general, a number of studies are now indicating that a reduction or change in ordering practices is needed in order to reduce variation between physicians and to ease costs on healthcare systems.
Interestingly, many of the IVD markets in question are expected to grow over the next decade, despite this shift in attitudes. This forecast growth is due to a multitude of factors including increases in overall population size, ageing populations, rising disease incidence, and improved disease awareness.