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Emerging Technologies for Point-of-Care (POCT) Testing: A future outlook for Scientists and Engineers

Authors:

Abstract

A large number of laboratory tests are now available in different POCT formats, so that it is often possible to perform high quality laboratory diagnostic testing, even without a high degree of expertise in medical technology. This has allowed the development of new approaches to laboratory care in medical practices and in hospitals. Nevertheless, the justification for POCT analysis must be scrutinized in individual cases and compared with other organizational solutions. In the interest of optimal patient care, it must also be remembered that uncritically selected PoCT methods cannot replace the expertise of a medical laboratory. PoCT technologies can be split into two categories. Of the two major categories the first is small handheld devices, providing qualitative or quantitative determination of an increasing range of analytes. The second category of devices are larger, often bench-top devices which are essentially laboratory instruments which have been reduced in both size and complexity. These include critical care analysers and, more recently, small haematology and Immunology analysers. This area is likely to grow with many devices being developed and is likely to reach the commercial market in the next few years. At the outset, the increasing use of POCT procedures appears to be in contrast to current tendencies towards centralization in laboratory medicine. However, on closer examination it becomes clear that the use of POCT can create a new balance between rapid acute on-site diagnostic testing and consolidated economic routine and special analysis in a large regional hospital laboratory or practice for laboratory medicine
review Article
Emerging Technologies for Point-of-Care Testing : A future outlook for
Scientists and Engineers.
Mr. Umesh Gami, Dr. Raji Pillai, Dr. Susan Cherian
Pathology Unit, Medical Division, Bhabha Atomic Research Centre, Anushakti Nagar, Mumbai – 400 094.
E mail : ukgami@yahoo.com, ukgami@barc.gov.in
Abstract
A large number of laboratory tests are now available in different POCT formats, so that it is often
possible to perform high quality laboratory diagnostic testing, even without a high degree of
expertise in medical technology. This has allowed the development of new approaches to laboratory
care in medical practices and in hospitals. Nevertheless, the justification for POCT analysis must be
scrutinized in individual cases and compared with other organizational solutions. In the interest of
optimal patient care, it must also be remembered that uncritically selected PoCT methods cannot
replace the expertise of a medical laboratory.
PoCT technologies can be split into two categories. Of the two major categories the first is small
handheld devices, providing qualitative or quantitative determination of an increasing range of
analytes. The second category of devices are larger, often bench-top devices which are essentially
laboratory instruments which have been reduced in both size and complexity. These include critical
care analysers and, more recently, small haematology and immunology analysers. This area is likely
to grow with many devices being developed and is likely to reach the commercial market in the
next few years.
At the outset, the increasing use of POCT procedures appears to be in contrast to current tendencies
towards centralization in laboratory medicine. However, on closer examination it becomes clear that
the use of POCT can create a new balance between rapid acute on-site diagnostic testing and
consolidated economic routine and special analysis in a large regional hospital laboratory or
practice for laboratory medicine
Introduction :
With emerging technological innovations in healthcare, including Smartphone apps, biosensors,
lab-on-a chip, and wearable devices—all of which offer a closer connection to the patient—point-
of-care (POC) technologies are quickly becoming part of the transformation of the healthcare
landscape. The driving concept in support of point of care testing (POCT) is to bring testing closer
to the patient and results conveniently and quickly to the provider to expedite diagnosis and
subsequent treatment. POCT allows for faster clinical decisions in hospitals, physician’s offices,
ambulances, patient homes, and in the field.
POCT is defined as “testing that is performed near or at the site of a patient with the result leading
to a possible change in the care of the patient.” Because of its convenience, timeliness, and potential
to improve patient outcomes, POCT’s popularity has risen in recent years.1 Empowering providers
to make decisions at the patient’s side has the potential to significantly impact healthcare delivery
and to help address challenges of health disparities. Moving the test to the patient increases the
likelihood that the patient, physician, and care team will receive the results faster, allowing for
immediate clinical management decisions. Furthermore, development, implementation, and
connectivity of portable diagnostic and monitoring devices for POCT will be part of a successful
shift from curative medicine to predictive, personalized, and pre-emptive medicine.
Explosion of POC Technology
A number of factors, such as the increasing prevalence of infectious diseases in developing
countries, the rising incidences of lifestyle diseases such as cardiac diseases and diabetes, the rising
usage of home based POC devices, and technological advancements with regard to development of
advanced, faster, and easy to use devices are stimulating the demand for POCT (see Table 1).2
While POCT is one of the most active segments within the diagnostic industry, the technological
capabilities far outnumber the rate of POCT adoption.3
Table 1: Factors Stimulating POCT Demand
Healthcare reform and patient-centered care
Technological advancements (faster, easier-to-use devices)
Laboratory staff shortages
Increasing older population and more chronic disease
Rising incidence of lifestyle diseases (e.g., cardiac, diabetes)
Increase in home-based POC usage
Increasing trend toward healthcare decentralization
Long-term savings
Rural locations with limited lab services
Prevalence of diseases in developing countries
Types of PoCT Technology
A typical classification of PoCT technology splits devices into small handheld ones including
quantitative and qualitative strips, and those which are larger bench-top devices with more complex
built-in fluidics, often variants of ones used in conventional laboratories. It is possible to identify a
number of key design components that are incorporated into all devices, the collective aim of which
is to achieve, as far as possible, all the desired features that were discussed in the previous section.4
Although not all are present in the simpler devices such as dipsticks, these key design components
are shown in Table 2. With the trend of increasing miniaturisation of devices and the application of
technologies developed in relation to consumer electronics, it is becoming increasingly possible to
make smaller and smaller devices that incorporate all of these key design features.
Table 2. Key design components of PoCT devices.
Operator interface
Bar code identification system
Sample delivery devices
Reagent storage and availability
Reaction cell
Sensors to detect the measurement reaction
Control and communication systems
Data management and storage
Manufacturing requirements
Market Growth of Point-of-Care Testing
Various reports are available to document the growth in in vitro diagnostics (IVD) markets
including various categories such as PoCT. In light of the many factors increasing the demand for
POCT, manufacturing companies are pushing the envelope to make POCT devices faster, easier,
and more reliable. The global POC diagnostics market is forecasted to grow at a compound annual
growth rate (CAGR) of 9.3% from 2013 to 2018, and to reach $27.5 billion by 2018.2,5 The market
accounts for both professional and patient self-monitoring tests and includes testing kits for:
Blood gases/electrolytes
Cardiac markers
Cholesterol/lipids
Coagulation monitoring
Drugs of abuse testing (DAT)
Fecal occult blood
Food pathogens
Glucose monitoring
Hematology
Infectious diseases
Pregnancy and fertility
Tumor/cancer markers
Urinalysis testing
Advances in Technology
The POCT market is driven by technological advancements as well as by patient preference.
Manufacturers are making continuous progress in terms of research and development to create
products with newer, advanced technologies. The technology involved in POCT has evolved in
many cases to be comparable to the centralized laboratory in terms of quality and meeting clinical
needs. Advancements have also been made that make testing simple enough to be correctly
performed by moderately trained staff. Many tests that previously required a laboratory for testing
can now be accurately tested at the point of care. Even more complex molecular diagnostic products
are being developed directly for the POC market.6
Required Features of PoCT Devices
Designers of PoCT devices start with the needs of their users and these needs will to some extent
depend on the clinical setting. However some features are common to virtually all users in all
settings. As documented by St John et al.,7 these key requirements include:
1. Simple to use.
2. Reagents and consumables are robust in storage and usage.
3. Results should be concordant with an established laboratory method.
4. Device together with associated reagents and consumables are safe to use.
Table 3. The assured guidelines that indicate the features that should be designed into all
PoCT devices.
Affordable – for those at risk of infection
Sensitive – minimal false negatives
Specific – minimal false positives
User-friendly – minimal steps to carry out test
Rapid & Robust – short turnaround time and no need for refrigerated storage
Equipment-free – no complex equipment
Delivered – to end users
Laboratory Staff Shortages
Laboratory staff shortages are another factor pushing the development of POC technology. Having
less trained staff available has led to an increased level of automation and self-contained systems
that require minimal user interaction.6 Skilled-staff shortages, especially in the field of diagnostics,
are expected to accelerate the market penetration rates of POC diagnostic products.
Current POCT Market Status
Hundreds of tests once considered too complex for POC are now routinely performed outside the
laboratory.8 Sensor technologies enable the rapid analysis of blood samples for many critical care
assays, including chemistries, electrolytes, blood gases, and hematology. Biosensors are used for
toxicology and drug screens, measurement of blood cells, coagulation, detection of cardiac markers,
and glucose self-testing.
POCT Benefits
While the most obvious benefit of rapid POCT is its potential to expedite medical decision-making,
there are a plethora of other probable benefits (see Table 4). For specific needs, POCT can be a
much more efficient method for diagnosis and rapid treatment. For example, if a patient has
influenza or another severe respiratory infection, meningitis, or a hospital-acquired infection, the
importance of receiving test results without delay and quickly administering treatment can make a
huge difference in positive patient outcomes. When properly integrated, POCT allows healthcare
workers to capture clinical data quickly and accurately, and streamline workflow and efficiency.
POCT, for the right tests in the right situations, can improve consistency, accuracy, patient
engagement, patient satisfaction, and ultimately patient outcomes.
Table 4: Benefits of POCT
Faster test results lead to more timely triage or treatment
Less sample volume (neonatal, pediatric, ICU benefit)
Tests at a variety of remote locations meet a diversity of medical needs
Decrease pre-analytical concerns related to processing of specimen. (e.g.,
clotting, centrifugation, etc.)
A Lean process
Increase provider and patient satisfaction
Reduce length of hospital stay
Reduce hospital admissions
Optimize drug treatments
Decrease inappropriate use of drugs
Reduce postoperative care time
Reduce ED time
Optimize clinical efficiency and use of staff time
Efficiency Advantages
Because on-site POCT typically requires fewer steps than the transporting, processing, and
aliquoting processes that take place in a core laboratory, it is inherently a leaner process.
Additionally, because the provider can examine the patient in conjunction with the POCT results, in
many cases medical care is more promptly implemented, eliminating the need for physicians to
remember a case after test results come back from the main laboratory. Additional improvements to
patient outcomes or workflow happen because POCT results can be linked to patient management
immediately in order to move patients through the system faster or handle more patients at a time.
Moreover, the rapid availability of POCT results allows for face-to-face instructions that can
improve patient understanding of treatment plans.
Challenges
Although POCT provides rapid results and the opportunity for faster medical decisions, the risk of
errors with POCT often raises concern over the reliability of test results. In contrast to the core lab,
where errors occur most frequently in the pre- and post-analytic phases, POCT errors occur
primarily in the analytic phase of testing. This can be related to a lack of understanding or training
of non-laboratory staff who are typically involved in POCT or as a result of test limitations and
misuse of POCT in extreme environmental conditions.9 While the laboratory offers a structured,
controlled testing environment, testing conditions for POCT can vary tremendously. Additionally,
the connectivity needed to get POCT results into the EHR fast enough to effect a change in patient
care is challenging.
Management/Oversight
o Infrastructure
o Lab must be involved
Testing Perfomed by Non-laboratory Personnel
o Need knowledge of specimen handling, QC, QA, PT, etc.
Analytical Quality
o Reliability of results
o Variations in test results from multiple testing platforms
Regulatory
o Waived vs. non-waived
Training & Competency Assessments
o Need to track for all operators
o Differing requirements between regulatory agencies and for waived vs. non-
waived
Data Management & Connectivity
o Need to capture results electronically (to reduce errors, incorporate data)
o Varying connectivity capabilities of POC devices
o EHR connectivity
Costs & Billing
o POCT and lab tests with the same name/CPT code can cause confusion
o POCT devices with multiple tests in one cartridge may not be reimbursed
properly
Future Outlook for POCT & Advancing Developments
The emphasis of care is shifting toward prevention and early detection of disease, as well as
management of multiple chronic conditions. With the development of smaller devices and wireless
communication, the way in which providers care for patients is changing dramatically and patients
are beginning to take a bigger role in their own healthcare. Healthcare will become more
personalized through tailoring of interventions to individual patients. The next decade will bring a
new realm of precision and efficiency to the way information is transmitted and interpreted, and
thus the way medicine is practiced. Diseases that currently require complex testing in a hospital
setting will be handled through bedside monitoring.10
An influential market driver for the in vitro diagnostics (IVD) sector is the emphasis on
personalized medicine, particularly in regards to selection of drugs that work best for an individual
patient based on genetics. Diagnostics are at the centre of achieving this goal, with direct and
immediate patient contact being the preferred route rather than working through a centralized
laboratory. In personalized medicine, the economic arguments for volume testing within a central
laboratory are outweighed in favour of POCT.11
A number of tests are being developed in POC, from new infectious disease biomarkers to
polymerase chain reaction (PCR) and molecular testing at the bedside. Wearable biosensors and lab
tests on a chip are no longer science fiction, but are actually in development. In addition to new
technologies, research findings, new regulatory scrutiny, and economic and business obligations are
pushing POCT to carve out a new niche within the healthcare system.
Government and industry initiatives are combining with research and clinical practice to steer
POCT into its next era.12 Look to see a continued increase in the use of POCT in home settings, on
smart phones that can monitor certain key parameters, and in primary care settings.
Common POCT
• Activated clotting
time
(heparin monitoring)
• Blood gases
• Glucose
• Hemoglobin
• Influenza
• Occult blood
• Strep
• Urine dipsticks
• Urine pregnancy
POCT with Variable
Usage
• Bilirubin
• Cardiac monitors
• Creatinine
• D dimer
• Hgb A1c
• Heparin
• HIV
• H. pylori
• Lactate
• Lipids
• Magnesium
• Microalbumin
• PT/INR
• Toxicology
POCT Emerging
• Anti-platelet therapies
• CBC
• Coagulation for
transfusion
• Platelet function
POCT Future
• ACTH
• DNA testing
• Endocrine testing
• Epidemics
• Gastrin
• Growth hormone
• Microbiology
• MRSA
• PTH
• Sepsis
• Stroke markers
Emerging PoCT Technologies
Many of the technologies currently being used for PoCT were generally devised decades ago and
have not changed in a fundamental sense in the intervening period. That is not to say that these
technologies have not been improved incrementally through advances in materials, electronics and
computing technologies amongst other developments. But new technologies that offer substantially
different capabilities and potential, and have made the difficult transition to market, are few and far
between. Below we briefly review those that may be commercial propositions in the coming decade
and two that are already commercially available.
Two decades ago there was much discussion about a concept called Lab on a Chip (LOC) and the
view was that this would become the dominant PoCT technology in the future. The development of
LOC, also sometimes referred to as microchips, grew from the microelectronics industry through
techniques of miniaturisation and microfabrication.4 Such devices have been defined as ones that
perform analysis at microscopic scales i.e. 1–500 µm and incorporate microfilters, microchannels,
microarrays, micropumps, microvalves and bioelectronics chips.4 The microchip integrates into one
reaction cell all the processes associated with analysis from the placement of the sample into the
chip to the analysis itself. Microchips can be fabricated from silicon, glass or polymer. Details of
this technology are not often found in the mainstream clinical laboratory literature but Bazydlo et
al. provide an interesting and detailed account of this important area.13 However despite the
continuing advances taking place in silicon chip manufacturing contributing to the exponential
increase in computing power from such chips, so-called Moore’s Law,14 these advances have not
yet translated into many commercial devices for PoCT. The notable exception is the i-STAT
technology, but there remains considerable interest and research in this area. There is even a
dedicated journal called Lab on a Chip , and as will be discussed below, potential products have
been described in the research literature. Translating experimental concepts into commercial
devices has proved difficult for many reasons, not the least of which is cost.
Due to slow commercialisation of the LOC concept, lateral flow strip (LFS) technology has
continued to dominate the PoCT market, as seen in many of the products described previously.
But lateral flow strips have a number of limitations and described in relation to particular
components of the strip by Wong et al.15 Collectively these limitations result in two major
disadvantages which make it difficult for LFS to meet the needs of some PoCT applications.
One such need is so-called multiplexing, namely the ability to measure multiple analytes on the
same strip. While this is not impossible using LFS it remains difficult to do for more than two or
three analytes.
The second major problem for LFS technology is limited sensitivity and this has been brought into
focus by the need for better technology for infectious disease testing, particularly in the developing
world. While there have been incremental improvements in the performance of strip tests for
various infectious diseases, a recent review shows that many do not meet the required sensitivity to
be practically useful.16 For example, with tuberculosis testing, several studies have shown that
current strip technology is neither accurate nor cost effective and the WHO has recommended they
should not be used in individuals suspected of active pulmonary or extra-pulmonary tuberculosis.17
With increasing focus on the link between infectious disease and poverty in the developing world,
there is a commensurate effort to develop better alternatives to strip tests for infectious disease
testing and improve global health. It is also important to emphasise that there is a considerable
burden of infectious disease in the developed world, including respiratory and sexually transmitted
infections, which also require better PoCT technology for faster diagnosis and treatment.
The search for better technologies has been directed down two interrelated pathways. One is the
continuing efforts to develop the LOC concept, particularly for detection of nucleic acids, and this
reflects the general trend in microbiology and infectious disease of serological assays being
replaced by molecular testing. The second is the development of paper-based analytical devices
which have the advantage that paper can be machined in similar ways to silicon but it is much
cheaper, an important consideration for devices in the developing world.
Although progress with developing the LOC concept has been slow, commercial devices using
molecular assays to detect infectious agents are starting to appear. There are many challenges
associated with developing point of care molecular tests, not the least of which is integrating sample
preparation with the other analytical sub-processes to produce a complete analytical process
requiring no operator involvement i.e. ‘sample in – result out’.18 Up until recently, all devices
required laboratory-like facilities to prepare the sample and avoid contamination, which is a major
barrier to using the device at the point of care. One device, the Cepheid GeneXpert system
described in more detail below, has managed to overcome this integration challenge although it
might be argued that it is not really a microfluidic device.
Another challenge is how to provide real-time amplification of the sample. PCR requires a source of
heat and therefore power, which may not be available in many developing world point of care
locations. Thus various isothermal and enzyme-free amplification techniques have been developed
such as loop-mediated isothermal amplification (LAMP) and rolling circle amplification (RCA).19
The third major component of point-of-care molecular devices is the type of detection and read-out
modality. Optical detection methods include absorbance, light-scattering and fluorescence based
measurements while some designs rely on electrochemical measurements.19 Of perhaps greater
significance is how the detected signal is presented to the user, particularly one using the device in a
remote location in the developing world. Several applications have been described of using mobile
phones and other telemedicine applications in order to link the person conducting the test to remote
expertise which can interpret the result and guide treatment.20
The GeneXpert system might be seen more as a system to automate PCR-based assays rather than a
PoCT device. But the ability of this relatively small bench-top device to perform real-time
quantitative PCR in approximately 90 min with minimal operator interaction means that it offers the
potential to perform rapid molecular testing in situations where the need for results is urgent.21 The
system uses single-use cartridges that each contain multiple chambers that hold the sample, various
purification and elution buffers, and all the PCR reagents including enzymes; in addition all waste is
retained within the cartridge. Attached to the cartridge is a PCR tube around which are heating and
cooling tubes together with optical blocks that perform the amplification and fluorescence based
detection of the products. Within the cartridge is a syringe body designed in such a way to virtually
eliminate sample contamination. Through a series of valves in the syringe, sample is moved through
the various stages of the PCR process using the reagents stored in the cartridge, and culminating in
real-time detection of the amplified products.22
Several evaluations have been performed of the GeneXpert system for a number of clinical
applications including infectious and sexually transmitted diseases, using various sample types.
Thus Spencer et al. showed the GeneXpert system had 100% sensitivity and specificity for
methicillin-resistant Staphylococcous aureous in paediatric specimens,23 while Buchan et al. tested
stool specimens and demonstrated near perfect sensitivity and specificity for Clostridium difficile
detection.24 An economic-based analysis of tuberculosis testing showed that the GeneXpert system
was also cost-effective.25
Another commercially available PoCT device for DNA testing is the Spartan RX™ platform which
detects mutations in the CYP2C19 gene. These mutations cause reduced response to clopidogrel, an
anti-platelet aggregation drug given to patients undergoing percutaneous coronary interventions
(PCI), and this can result in adverse consequences. PCIs are often performed urgently, hence the
potential benefits for rapid PoCT to detect mutations in the CYP2C19 gene and alternative drug
therapy with better outcomes. The Spartan desktop instrument can extract and analyse DNA from a
buccal swab. The latter is placed into a cartridge which is then inserted into the instrument and
results are available within one hour.26 There is limited data on the outcomes of using this test but a
recent pilot study of 137 consecutive subjects with acute coronary syndrome and undergoing PCI,
on whom the Spartan test was performed, suggests that the test was useful in identifying patients at
risk of a poor response to clopidogrel.27
Another promising technology for molecular and other types of testing is that being developed by
Atlas Genetics. The system comprises a test-specific disposable cartridge containing all the
necessary reagents to perform the test. The cartridge is designed to be run on the Atlas io™ reader.
Following inoculation of the specimen into the cartridge and insertion of the cartridge into the
reader, the test is performed under complete instrument control with no further user input required.
The test is based on three fundamental processes that occur sequentially on the test cartridge: (i)
DNA extraction; (ii) amplification using PCR; and (iii) detection of specific
DNA using an electrochemically labelled probe. The Atlas io™ reader uses pneumatic control to
transport the specimen around the various functions within the test cartridge. All reagents are
present on the test cartridge as either liquid reagents which are released under reader control, or as
dried reagents deposited into the appropriate chambers within the cartridge. These are reconstituted
as the specimen enters the chamber containing the deposited reagent. The system is capable of
multiplexing by virtue of a number of independent fluidic channels and the opportunity to use a
number of electrochemical labels.28,29
Much has been published in the research literature on the development of paper-based PoCT
devices including a comprehensive review by Yetisen et al.30 At this point it is important to
distinguish nitrocellulose which is in lateral flow strips from paper-based devices. Nitrocellulose is
a hydrophobic material which is good for binding to proteins but the hydrophobicity has other
disadvantages which paper can potentially overcome including being able to be patterned to form
microfluidic devices that are capable of multiplexing. Yetisen et al. identifies four capabilities of
such paper devices:
1. Sample can be dispensed into multiple spatially-segregated areas which enable simultaneous
assays to be performed on the same device.
2. Samples can move by capillary action so no pumps are needed.
3. Only small sample volumes are required.
4. No hazardous waste as the device can be incinerated.
Many groups including organisations such as ‘Diagnostics for All’ are developing such devices for
the developing world primarily because paper is a significantly cheaper material than materials used
in lateral flow strips. In addition, the potential applications are wider than the infectious disease area
with one group developing a paper microfluidics device the size of a postage stamp for
measurement of three liver functions tests so-called ‘Lab on a Stamp’.31 While the potential of
this technology is high, Yetison et al. comment that no mature platform for this technology has yet
appeared, let alone commercial applications.60 However Pollock et al. describe encouraging results
from a field evaluation of a paper-based device to measure alanine transaminase. 32
Conclusions
The volume of testing performed outside of the conventional laboratory will undoubtedly grow,
driven by the need to deliver care closer to the patient. In the last two decades the menu of tests that
can be performed using PoCT devices has expanded considerably. This has been achieved largely
using well-established technologies such as lateral flow strips but incremental improvements have
taken place in many areas so that devices are easier to use, they are less prone to errors, they are
more compact or smaller, and in many cases the analytical performance is now more than sufficient
for clinical purposes.
It is likely that such incremental improvements with existing technologies will continue as the spin
off from the continual miniaturisation of electronics and increased computing power that are taking
place in other markets such as consumer goods. Examples of technologies that look promising for
the future include contact lens glucose sensors,33 tattoo-based sensors34 and smart holograms,35 all
of which are very patient-centred in their configuration.
Yet there are clearly areas where new technologies are needed in order to deliver the required
analytical performance. Infectious disease is one such area where existing LFS technology is not
sufficiently sensitive and molecular techniques are seen as the future, both in the developed and
developing world. PoCT devices that use PCR to detect a number of different pathogens are just
starting to appear and in the next few years we are likely to see a number of these reach
commercialisation and be used at least within western healthcare markets. Given that the analytical
performance of these devices is well proven, the remaining challenge will be to see if they can be
produced at a price which will enable them to have an impact on dealing with infectious disease in
developing countries.
The final important issue is the ever important need to look beyond the technology and also
consider how the result is actually going to change the outcome for the patient test results alone
are useless. This review has concentrated on the analytical part of the technology and has not
considered how the result will be delivered to those who will use it to make decisions about
treatment etc. This post-analytical part of the testing process is dealt with in the accompanying
review of Informatics by Jones et al.36 But it is important to emphasise here that post-analytical
processes are as critical to the whole value proposition of testing as the measurement technology
itself. It is also probably fair to say that its importance has until recently been underestimated and
this has contributed to the criticism that much new technology does not deliver benefits in
proportion to the investment. This is particularly important for PoCT devices because there has
been a pre-occupation with the expense of a point of care test compared to one performed in the
central laboratory. Yet, as several studies have shown, when economic studies of PoCT are
performed that consider the complete testing process, including the patient outcomes, the PoCT
value proposition is shown to be favourable compared to the central testing model.25,37,38 Successful
innovation and the adoption of devices which improve patient outcomes in a cost effective way has
to include the process and economic changes that are part of the clinical and cost effectiveness
evidence – particularly the disinvestment of redundant resources.
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