• POCT implementation in the primary health sector

POCT implementation in
the primary health sector
Aalborg University
Department of Health Science and Technology
10th semester project
Frode Skjæveland
2006
1
Title: POCT implementation in the primary health sector
Semester theme: Biomedical Engineering and Informatics
Project period: 15.04.06 – 15.09.06
Project group: 06gr1087f Synopsis:
Project group members: The report analyses and discusses two
Frode Skjæveland essential aspects of implementing Point
of Care Testing (POCT) in the primary
health sector. A precision and accuracy
test conducted on venous, capillary
venous and restored venous blood in a
laboratory and ambulatory setting. The
analysis of the tests shows that the
measurement results are within
acceptable limits on all tests. It shows
that deviation from the test procedure
and thereby the experience level of the
operator has a significant effect on the
Supervisor: result.
Ole K. Hejlesen (MI, AAU) Further the report analyses and suggest
Søren K. Risom (Klinisk Biokemisk improvements to the health IT system
involved when implementing POCT
Laboratorie, Aalborg Sygehus)
devices in the primary health sector. In
order for shared care solutions to be
deployed, a more efficient
communication is required between the
clinicians and patient.
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Preface
This report is written by Frode Skjæveland at the Department of Health Science and Technology,
Aalborg University, Denmark. The author is pursuing a Master of Science program with
specialization in Medical Informatics1. The report is written in the period March 15th to September
15th 2006 as the master thesis on the 10th semester of the study program. It is primarily addressed to
other persons or organisations with interests in the field of anticoagulation, point of care testing,
implementation and testing of laboratory equipment and IT systems for communication between
hospitals and the primary health sector.
The project has been pursued in thigh collaboration with Zafena AB. This Swedish company has
embodied two inventions of Mats Rånby and brought to market a Point of Care (POC) testing
devise for PT-INR for monitoring of blood thinning therapy, Simple Simon PT. A theme of the
inventions is to increase the analytical quality in POC testing, and it is being established that Simple
Simon PT represents major steps forward with regard to precision and accuracy, see www.zafena.se
and the links to published patent applications [1-4]. The present project involves furthering the
concepts of the inventions by increasing the information handling capabilities of the accurate and
precise POC testing product mentioned. The realization of the project was facilitated by VINNOVA
awarding Zafena a grant to collaborate with the County Council of Östergötland and Aalborg
University in devising a full scale “demonstrator” within a project plan entitled “IT support in
Health Care Controlled, Diststance Independent, Monitoring of Blood Thinning Therapy”.
The author would like to thank Mats Rånby (CEO, Zafena), Xerxes Rånby (SW/HW, Zafena),
Marie Danielsson (QA, Zafena), Søren Kristensen Risom (Dr. Med Ledende overlæge, AAS),
Liselotte Lidner (IT manager, AAS) and Jane Bech (Bioanalytiker, AAS) for their valuable
contribution to the project.
Thanks to Lars Heyckendorff Lilholt and Maria Tatiana Crespo for general feedback and support.
1
Informatics applied to medicine, health care and public health
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Table of contents
Preface ..................................................................................................................................................3
Introduction ..........................................................................................................................................6
Problem background.............................................................................................................................8
Oral Anticoagulant Treatment (OAT)..............................................................................................8
Treatment regimes........................................................................................................................9
Conventional Treatment ...............................................................................................................9
Patient Self-Management (PSM) Treatment ..............................................................................10
Patient group...................................................................................................................................11
POCT..............................................................................................................................................11
Problem definition..............................................................................................................................12
Method................................................................................................................................................13
Problem analysis.................................................................................................................................15
Measurement methods and the INR value .....................................................................................15
POCT implementation in the Primary Healthcare Sector ..............................................................15
The conventional INR analysis ..................................................................................................16
Shared care .....................................................................................................................................16
Simple Simon® PT ........................................................................................................................19
IT Analysis .....................................................................................................................................20
Thrombobase/AK-Skema (IBM)................................................................................................21
Laboratory systems.....................................................................................................................23
GP Patient Administration Systems ...........................................................................................23
Sundhed.dk .................................................................................................................................25
EDIFACT standard.....................................................................................................................26
POCT standard ...........................................................................................................................28
Laboratory precision test of Simple Simon PT ..................................................................................30
Test setup........................................................................................................................................30
Analysis methods ...........................................................................................................................31
Practical conduction .......................................................................................................................32
Results ............................................................................................................................................33
Interpretations and discussion of results ........................................................................................36
Ambulatory precision test of Simple Simon PT.................................................................................42
Test setup........................................................................................................................................42
Practical conduction .......................................................................................................................43
Results ............................................................................................................................................44
Interpretations and discussion of results ........................................................................................46
IT Architecture ...................................................................................................................................50
Industry standard ............................................................................................................................50
The national standard – Sundhed.dk ..............................................................................................52
Improvement of the system ............................................................................................................53
Two way communication ...........................................................................................................54
Electronic integration of POCT devices.....................................................................................55
Discussion ..........................................................................................................................................56
Perspective..........................................................................................................................................57
References ..........................................................................................................................................58
Appendix A: Simple Simon PT product information.........................................................................61
Appendix B: Clinical test data............................................................................................................62
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Appendix C: Interviews, meeting protocols.......................................................................................66
Møte med Gunilla Eriksson vedrørende demonstratoren...............................................................66
Appendix D: Laboratory test ordering form.......................................................................................70
Appendix E: Patient consent form......................................................................................................72
5
Introduction
In an audit project conducted by Dansk Institut for Folkesundhed (DIFF) it was stated that 1.8
million people (about 36% of the population) suffer from a chronic disease [5]. A chronic disease is
defined2 as a disease with one or more of the following characteristics; causes non-reversible
pathologic changes, demands a special rehabilitation, or is expected to demand a long lasting
monitoring, observation or treatment. About 80% of the total healthcare expenses are used to
monitor, observe, and/or treat this patient group [6]. It is estimated that there will be a yearly growth
rate between 0.7 and 1.8 % of patients with chronic diseases, mainly due to demographic
development [5].
The 8 most common chronic diseases are responsible for 7.7 million consultations at General
Practitioners (GP). A large number of the patients are on medical treatments that require monitoring
of blood or urine values. The traditional way is to send a blood sample to a hospital laboratory and
then receive the result a few days later.
During the last years there has been a strong focus on Point of Care Testing (POCT), which is
defined as “Diagnostic testing performed at or near the site of patient care” [7;8]. In the
Scandinavian health care system there are specially educated laboratory consultants that assist the
primary sector with implementing POCT equipment. There is also a Scandinavian organisation for
testing of laboratory equipment for the primary healthcare sector called SKUP. SKUP published
their first reports in 1999, at this time only 4 devices were evaluated. Today about 50 devices are
tested covering 9 different kinds of blood parameter tests3. According to Danish Medical
Association (PLO) latest status report (1999) 99% of all GP have their laboratory facilities [9].
There are two important incentives for GP to use POCT, an economical and to improve
communication with the patients. When performing laboratory test in the clinic, the patient will get
an instant feedback on the results. For chronic patients on medical treatment, the dosage is usually
regulated from a test result, e.g. a diabetic patient will adjust the insulin dosage according to the
glucose level. The results serve as a parameter that is used to make a decision about the treatment.
In the case of an abnormal result, it is possible for the GP to discuss the possible reasons for this
with the patient and make a qualified decision. In the case where an external laboratory is used, the
GP would need to contact the patient. The patients also have to wait for a result, which in many
cases can be stressful.
Two treatment regimes that have been evolving in parallel with moving the treatment and
diagnostic testing closer to patient are home monitoring and self management. The idea is that
patients learn to live with and understand their disease through a systematic educational and
rehabilitation program administered by the hospital. A patient’s knowledge about symptoms, factors
that affect the disease, treatment and behaviour can improve the life quality and make the patient
less depended of health care services.[10] In many cases these regimes the patient have to use
POCT devices, e.g. diabetic patients use glucose meters. This requires the equipment to be user
intuitive, user friendly to reduce the risk of errors.
Moving diagnostic testing equipment out of the laboratory environment also presents new
challenges to solve. In a clinical biochemical laboratory a specially trained bioanalyst will perform
2
Defined by Sundhedstyrelsen [6]
3
http://www.uib.no/isf/noklus/skup/
6
the test according to procedures in a controlled environment. The design of the POCT device and
the procedures must be easy understandable. The most essential area is the quality of results; all
clinical biochemical laboratories use external quality assurance (EQA) institutes. Participating in
EQA is a claim for accredited laboratories. The frequency of EQA varies between 1-2 times a year
till 12 times a year. Often different EQA materials are used from time to time which means that the
laboratory does not know the “true” value in advance [11]. One the problem with POCT devices is
that they sometimes based on other methods than the ones used in the accredited laboratories. This
makes the control difficult and introduces uncertainty to the measurement results.
Oral anticoagulation therapy (OAT) with Vitamin K antagonists is an efficient treatment used to
reduce the risk of venous thromboembolism without resulting in a significant increased risk of
bleeding [12]. In the Scandinavian countries about 1% of the respective populations are in OAT
[13;14]. During the last years the amount of patients has been increasing, from a prevalence of 663
patients per 100.000 in 1997 to 784 in 1999. This is mainly because of new indicators for long term
OAT [14].
The increasing number of patient on OAT has initiated research in applying new methods for
monitoring and administration of the patients. During the last 10 years there has been several
studies where the patient is directly involved and to a greater extent responsible for the treatment.
This is referred to as Point of Care (POC) treatment and involves the use of Near Patient Testing
(NPT) devices. POC opens new possibilities by using information systems for communication
between the patient, clinicians and the clinical laboratories.
How should POCT be implemented, using anticoagulant treatment as an example, to benefit the
health care system and patient, without comprising quality of test?
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Problem background
In this section the traditional OAT and the patient group will be described. Two treatment regimes
will be analyzed, the conventional treatment administered by a specially trained clinician or GP and
the home monitored treatment.
Oral Anticoagulant Treatment (OAT)
The aim of Oral Anticoagulant Treatment using vitamin K antagonist is to reduce the risk of
thromboembolic events while not significantly increasing the risk of bleedings. OAT can be acute
in a thromboembolic event or long lasting when treatment patients with an increased risk of
thromboembolic events.
The treatment is complicated because of dose-response variance, inter- and intra individually. For
this reasons it is necessary to control the dose of anticoagulant agents by getting INR
measurements. For the different treatment indications there are goal values and therapeutic
intervals, that are a compromise between the risk of bleeding and thromboembolic events.[15]
Figure 1: Risk of death associated with different levels of anticoagulation
There are many pharmacologic products that can be used to inhibit the coagulation system. In
Denmark there are two registered drugs for OAT; warfarin and phenpocumon. They are both
Vitamin K antagonist, pharmaceuticals that reduce the production of normal coagulation factors.
The most common used drug in Denmark is warfarin [16].
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Treatment regimes
In Denmark there are two treatment regimes; Conventional (hospital/GP administered) and patient
self management. The physiologic coagulation process is very complex, which also makes any
attempt to control process non trivial. The treatment is adapted is to each patient and it requires a
knowledge about dosage-response correlations and thereby the clinicians expertise, experience and
patient interaction [17].
Conventional Treatment
The majority of the patients are in conventional treatment, which means they are treated by at their
GP or at the hospital. If they are treated at the hospital they are managed by a specialist in a ward,
outpatient clinic or anticoagulation clinic. [18]
Figure 2: Conventional (Hospital/GP administered) AC treatment. The patient visits the clinic and gives a blood
sample; depending on the analysis the clinician will give an instant or delayed feedback.
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Patient Self-Management (PSM) Treatment
Patients in self-management treatment measures their INR value, and registers the INR values and
dosages on a paper chart. This chart is sent to the specialist every three months. The responsible
clinician evaluates the data and gives feedback to the patient. If the treatment is not satisfying, i.e.
the patients INR is not in the therapeutic interval or it is fluctuating, a consultation will be arranged
so the reason can be clarified. In order for PSM to work it requires that the patient is self disciplined
and has a clear understanding of the consequences of not taking the treatment seriously. It is
essential that the INR measurements are done on a regular basis and that the dosage of medication
is managed according to the results.
Figure 3: Patient Self-Management Treatment. The patients measures and registers INR values and dosages on a
paper chart which is sent to clinic.
To be qualified for PSM a patient must be in long-term OAT and must have an interest in
maintaining the treatment. The AC centre does not offer patients PSM, they have to take the
initiative. This means that only patients with interest and motivation can enter the program. The
clinical specialist has to approve patients who apply for PSM. After getting approved the patient is
educated in the different aspects of the treatment, so they get a deeper understanding about the
practical and theoretical aspects of OAT. In Denmark there are five centres for PSM located in
different parts of the country; in total 1800 patients are in PSM treatment.
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The patients in PSM treatment is in many ways the elite patients in OAT, considering it is the
patients who from own initiative applied to join the program and then is filtered by a clinical
specialist. It reasonable to assume that the patient group has a very high compliance, both because
of their motivation level and the understanding of the consequences of not taking the treatment
serious.
Patient group
The age distribution can be seen on figure 2, it show the increase in patients in Denmark from 1998
to 2002 in the different age groups. Approximately 77% of the patients are over 60 years old and
the median age is 71 [16].
Prevalence of AKV-users in DK
60,0
Total number of patients
1998 1999 2000 2001 2002
50,0 36.199 39.782 43.288 46.633 50.579
40,0
Users per 1000 inh
1998
30,0
2002
20,0
10,0
0,0
15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90+
Figure 4: The age distribution and change in prevalence from 1998 to 2002 in Denmark. It can clearly be seen
that the majority of the patients are over 60 years old and the prevalence has increased from 1998 to 2002 [16].
POCT
As mentioned Point of Care Testing refers to diagnostic testing performed at or near the site of
patient care. There are two major incentives for POCT is to eliminate the risk of pre analytic errors
occurring because transport. The other reason is the time perspective for the patient; POCT enables
the clinician to give an instant feedback and discuss the result with the patient. It also enables
patients to manage their own treatment, for example diabetics. From a patients point of view getting
an instant feedback eliminates the uncertainty of waiting for a test result and can make the patient
11
more involved in the treatment. Patient involvement in treatment has been proven to have good
results on the clinical outcome.
The existing laboratory procedures for the various tests are well established and have been
developed over years. They have quality assurance systems, both internal and external to ensure a
high quality on a local and national basis. By introducing POCT that are based on other methods
and are conducted by untrained staff, it is crucial to focus on building system to maintain quality
under these new circumstances.
Problem definition
As described in the previous sections there is a growing number of patients in life long OAT.
The process of monitoring and administrating these patients is not trivial, for many reasons:
• It requires a deep knowledge about the patients and the OAT
• It requires patient involvement and understanding
• It requires constant monitoring of the patient INR and adjustments of the medication
A number of technical solutions have been developed for support the monitoring and treatment of
this patient group. These solution range from the instruments to determine INR to high level
information system, making it possible to keep track of individual patient and exchanging
information with other parts of the health care system. Figure 5 illustrates the structure of this
project, where the technological solution for support OAT is divided into different layers. Each
layer has its own complexity, but they are all connected and depended on each other to make an
integrated solution.
Figure 5: Layer representation of POCT
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This project is limited to investigating and discussing two main questions:
• Is the analytic quality significantly reduced using POCT devices for OAC?
• How can IT systems be used to promote the cross sector cooperation in monitoring and
administrating patients in OAT?
Method
Methods used for gathering knowledge are either qualitative or quantitative depending on how they
are planned and conducted. A quantitative method is used to map the extent of the matter
investigated, whereas the qualitative method is deals with content and substance. Interviews and
questioners capture meanings, where observations make it possible to look at the context and
actions. The methods capture different aspects that in many cases can supplement each other.
It is often beneficial to first get data using qualitative methods to get a clear understanding of the
investigated subject and then use quantitative methods to get representative information from a
larger group of people or information sources. When selecting methods it is of main importance that
the methods can help to produce results that are representative for the problem area. To try to
eliminate potential project biases, effort has been made to use different methods for gather
representative information.
To answer the question on the problem definition general background knowledge was gained by
performing a structured literature search. A lot of effort was also put into making contact to extern
people with relevant knowledge for the project.
A literature search was conducted to find general information on OAT, methods for determining
INR (Owren’s and Quick). The literature was not restricted at first; it was structured as a screening
of possible relevant material. Later in the process publications and articles published about OAT
relating to Scandinavian countries were prioritised high. The context and structure of the health
system is very relevant in organisation of treatments. Knowledge about the local context is crucial
when analysing IT related matters.
External resource persons were used to a great extent. The author participated at relevant
Scandinavian conferences (Nordic Coagulation Conference, Malmø 2006 and Scandinavian Health
Informatics Conference, Aalborg 2006). A number of persons, both from a business and research
background were contacted and contributed to the project. Mats Rånby (PhD, CEO Zafena) gave
technical and general information matters relating to INR measurement and quality control systems.
Søren Risom Kristensen (PhD, Dr.Med) helped setting up clinical trials at the hospital laboratory
and the biochemical ambulatory. He also gave general input relating to OAT and other clinical
aspects. LiseLotte Lidner (IT manager, Clinical Biochemical Laboratory), Gunilla Eriksson (IT
manager, Clinical Biochemical Laboratory) and Hasse Eriksen (CEO, IntraMed) have valuable
information about the IT systems involved in OAT. Jane Bech (Bioanalyst) provided a lot of
general knowledge about practical aspects relating to OAT.
Two studies were carried out to produce results about the analytic quality and the practical
operation of POCT instrument Simple Simon PT.
13
Part 1 - Analysis
14
Problem analysis
In this section the background and different aspect of the problem will be described. The section
starts by describing the technical methods behind the INR value and POCT implementation in the
primary health care sector. After this the organisation of the treatment and relevant existing IT
system to support this is described.
Measurement methods and the INR value
The International Standardized Ratio (INR) was introduced by WHO internationally in the mid
1980, it was recommended that the INR should be used in all scientific literature and in patient care
[19;20]. INR makes it possible to issue global unambiguous treatment recommendations for
different medical indications [21]. The INR should be unaffected by reagent, instrument, physical
conditions (temperature etc).
INR = (testsec / normalplasmasec)ISI
The ISI value is calculated by the laboratory on a specific instrumentation and reagent using a
standardized ISI kit (issued by DEKS4 in Denmark). It is the relationship between the PT
(Prothrombin Time) of the test and normal plasma decides the INR, the ISI is a correction factor.
The time is measured from the instant where the normalplasma or the test is mixed with the reagent.
There are two different methods to determine PT, the coagulation activity of the blood, Owren’s
method and the Quick method. The Quick method measures the coagulation activity on the
“external coagulation system” factors (fibrogen, FII, FV, FVII and FX). Owren’s method measures
the coagulation system factors FII, FVII and FX, which are the ones that are affected by warfarin in
the liver. It has been shown in studies that there is a non-linear correlation between Owren’s and the
Quick method and that using different reagents for the same measurement method produces
deviating results.[22;23] This shows that there is a need for testing the POCT instruments with a
clinical biochemical laboratory and to establish a quality assurance program to ensure correct
measurements.
POCT implementation in the Primary Healthcare Sector
Implementation of new technology in an established organisation affects the workflow and the case
of POCT it changes the way clinical results that are used to make decisions about treatments are
done. It involves acquiring new equipment, introducing new procedures, quality assurance
programs, maintenance, and education of clinical staff. This is not a task the average GP is
competent for; it is a domain of technical laboratory staff at hospitals. For this reason all counties in
Denmark have laboratory consultants for assisting the GPs. In order for a GP to get refunded for test
performed in the clinic laboratory, it required that the GP is using the laboratory consultant [24].
There are two organisations in Denmark that have special interests on different levels in the
implementation of POCT in the primary health sector; SKUP5 and DBIO6. These organisations
4
Danish Institute for External Quality Assurance for Laboratories in Health Care (www.deks.dk)
5
Skandinavisk Utprøving af Labratorieutstyr til Primærsektoren (www.skup.dk)
15
have a direct or indirect consulting role for GP in the process of acquiring, implementing, operating
and quality assuring POCT instruments.
SKUP’s objective is to acquire and communicate technical documentation about the analysis quality
of medical laboratory analysis instruments that can be used in the primary health sector to the
clinical staff. There are 5 elements in SKUP’s quality assurance program which cover the quality
assurance, maintenance, instructions, procedures, education and logistics [25].
DBIO’s objective is in many ways overlapping with SKUP, the difference the level they operate on.
SKUP is working on a national level, where DBIO is the one who actually execute the plan and
have direct contact with the individual GPs.
The conventional INR analysis
The most common way to analyse INR in Denmark is that a blood sample is sent to a central
hospital laboratory. This laboratory has an IT system where it stores the results for longer or shorter
period of time. Most of these IT systems use an ID system which makes it possible to trace the
doctor who ordered the test, the patient who was tested and previous measured values for the same
patient.
Shared care
The increased pressure on the health service has spawned innovative thinking in the organisational
and technology supported ideas. One of the initiatives focuses on cooperation between GP’s and
hospitals. The idea is that this will lead to better utilisation of specialist medical capacity, improved
treatment quality for the involved patients and more appropriate use of resources. This type of
formalised cooperation is termed “shared care”. This section is written using the following literature
[26].
Figure 6: The three components of OAT
In terms of quality a correct OAT is depended on three factors; patient involvement in the treatment
process, routine controls where effect of the medication is controlled and a general review of the
medication. This ideal process is not typical for the way the treatment is conducted in the present
system.
It is crucial that the patient understands and accepts the treatment to get motivated show up at
routine controls and that the control works in a way that the patient feels is acceptable. If the patient
does not show up at routine controls it will have a very negative effect on ability to evaluate and
adjust the treatment. It is essential that the patient establishes a trustful relationship with the GP and
tell about the lifestyle and factors that affects the treatment.
6
Danske bioanalytikere (www.dbio.dk)
16
During the routine control the patient and GP talk together and a blood sample is taken. The sample
is analyzed in the GP’s laboratory or sent to the hospital laboratory. If the patients INR is within
therapeutic range, no change in the medication is done. There are three things that are important in
looking at the routine control: The first is that it requires a patient involvement, that the patient
understands and accepts change in medication. The second is that because of the continuity in the
treatment it is necessary to document details regarding the lifestyle of patient and the blood sample
test results. And the third is that it is potentially problematic if two different doctors are responsible
for routine control and re-evaluation. This is because it can be difficult to transfer the knowledge
about the patient health from doctor to doctor.
The re-evaluation should be performed periodically; the interval should be adjusted according to the
state of the treatment for the individual patient. In these re-evaluations a historic analysis should be
conducted, where the whole disease progress is used. It is also very important to involve the patient
in this process. If this it not done, patients get frustrated and feel that it not necessary to get
involved in the treatment.
Understanding the patient’s disease is necessary for both patient and the doctors involved in the
routine control and/or re-evaluation. The understanding is increased if the patient is heavily
involved and voluntary gives information about his/her lifestyle. If the patients conceive the
treatment as being an “expedition” their motivation to give information will fall. The consequence
is that the GP understanding for the patient will decrease.
The other factor that affects the treatment is the GP way of reacting to changes in the INR. In a post
analytical external quality assessment study of OAT in primary healthcare conducted by a
Norwegian research group this was shown [27]. The study was conducted using a questionnaire
including 2 case histories with familiar indications for OAT sent to 3781 GPs. 1547 GP (41%)
responded which is satisfactory by NOKLUS7 considering the nature of the study. Figure 7 shows
the difference between the INR result stated by the GP to decrease the warfarin dosage and the
same GP’s higher therapeutic limit. A positive value means that the GP decreased the warfarin dose
when the INR result stated was above the GP’s own higher therapeutic limit, and a negative value
means that the GP decreased the warfarin dosage when the INR value was within the therapeutic
interval. Most GP’s estimated an unrealistically high risk of serious bleedings. The critical
difference necessary to change the warfarin dose was highly depended on perceived therapeutic
intervals, and about half of the GP’s suggested a critical difference of 0.8 INR. The study concluded
that gross variations in practice were found, especially for aspects of the treatment with a lack of
uniform guidelines. It further concluded that evidence-based and practicable recommendations for
OAT are still needed.
7
Norwegian Centre for Quality Improvement of Primary Care Laboratories
17
 Figure 7: Case where the patient with a former pulmonary embolism had an INR value of 5.9
The study conducted actually proves there is genuine need to improve the organisational aspects of
the treatment. In the traditional OAT showed in Figure 6 the treatment is conducted in a series of
events. Implementing a shared care organisation would make the three components depended of
each other, like showed in Figure 8. It can be seen that the patient understand is central and routine
control re-evaluation is conducted by two different clinicians.
Figure 8: OAT in a shared care setting, the figure shows the dependency between the segments of the treatment
18
Simple Simon® PT
Simple Simon PT is an instrument used for measurin