<!DOCTYPE article PUBLIC "-//NLM//DTD JATS (Z39.96) Journal Archiving and Interchange DTD v1.0 20120330//EN" "JATS-archivearticle1.dtd">
<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Cross4all Project Model of Integration of Healthcare Data Using the Concepts of EHR and PHR in the Era of IoT</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Andrijana Bocevska</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Snezana Savoska</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Blagoj Ristevski</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Natasha Blazheska-Tabakovska</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Ilija Jolevski</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Vladimir Trajkovik</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Faculty of Computer Science and Engineering, “Ss. Cyril and Methodius” University Skopje Republic of North</institution>
          <country country="MK">Macedonia</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Faculty of Information and Communication Technologies - Bitola, University “St. Kliment Ohridski” University - Bitola</institution>
          ,
          <addr-line>ul. Studentska bb 7000 Bitola</addr-line>
          <country>Republic of North Macedonia</country>
        </aff>
      </contrib-group>
      <fpage>165</fpage>
      <lpage>177</lpage>
      <abstract>
        <p>Many efforts are made to integrate healthcare data, hospital information systems data, clinical and medical data to provide healthcare data analysis to be suitable for healthcare decision-makers. All these heterogeneous data are stored in many different places, formats and heterogeneous platforms and their integration is a very challenging and demanding task and sometimes even impossible. The existence of patients' related healthcare data issues is evident, although they are stored in various hospital and public health systems such as Electronic Health Records, healthcare institutions and laboratories, patient's health records, medical records. In this paper, we describe the Cross4all project model of integration of healthcare data into Personal Health Records with a focus on the patient, into the cloud environment with required data security and privacy standards.</p>
      </abstract>
      <kwd-group>
        <kwd>Health Data Integration</kwd>
        <kwd>Electronic Health Records</kwd>
        <kwd>Personal Health Records</kwd>
        <kwd>Wearables</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>Introduction</title>
      <p>Today’s trends of collecting data from healthcare and medical issues, from
different sources as hospital information systems (HISs), Electronic Health
Records (EHRs), medical prescription, diseases diagnoses and treatments
demand a serious approach to an ontology-based collection of data according to
HL7 standard and healthcare data security and privacy demands. Healthcare data
are owned by many healthcare providers and are not accessible to patients. Data
can be depersonalized and only used by decision and policymakers if they are
integrated. A lot of research is dedicated to depersonalized medical and health
data integration intended for the municipality, state and hospital management
structures. If we take into consideration data collected from many wearables that
support the ambient assisted living (AAL) concepts and help to improve medical
and healthcare, the integration of patient’s healthcare data is very important.
Many heterogeneous data in the personal health record are added from the sensors
as part of the Internet of Medical Things (IoMT) concept, trackers for human
behavior and vital signs of life, as well as exposome data.</p>
      <p>Strong security standards for healthcare and medical data for patient’s
centric systems with personal health record (PHR) are implemented regarding the
secured share of healthcare data with a temporarily selected doctor. This concept
demands a complex cloud infrastructure, with security and data protection
procedures, made according to the national protection law. The standards as HL7,
FHIR, open EHR and codding systems as ICD10 are also necessary to be used.</p>
      <p>The paper is structured as follows. The second section provides related
works, whereas the third section highlights the patients’ data privacy toward
securing their electronic PHR (EPHR) data, as well as the reusability of EPHR
data, usage possibility and usage disadvantages. In the subsequent section, we
describe the Cross4all project model of integration of healthcare data into PHR,
providing practical examples of model implementation in the project activities.
The final section gives concluding remarks and points out some directions for
future works.
2</p>
    </sec>
    <sec id="sec-2">
      <title>Related works</title>
      <p>
        Many efforts were made by researchers in the health and medical domain
to provide reusing of healthcare data. A model for decision makers’ support
according to the national law, using Spark, Mongo DB and DL-bases AI module
for NLP is proposed in [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. The interoperability among EHR systems, the full
integration of clinical data within PHRs and the exploitation of the contained
information is a widespread target internationally.
      </p>
      <p>
        An open data integration platform for patient, clinical, medical and
historical data, siloed across multiple HISs is proposed in [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. The platform was
adopted and implemented to address patient-centered healthcare and clinical
decision support requirements in a sports injury clinic at a not-for-profit
private hospital in Australia. It can accommodate and integrate further
heterogeneous data sources such as data streams generated by wearable IoT devices.
The distribution of scanned documents at one health institution and the design
and evaluation of a system to categorize documents into clinically relevant and
non-clinically relevant categories as well as further sub-classifications were
described in [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ].
      </p>
      <p>
        A method for digitizing the concept of health by processing the existing
information in EHRs with the help of several dedicated services was presented in
[
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. It introduces the “health digital state” (HDS) as a digital equivalent to the
“health” concept. A business use case that is extremely common in current
medicine: the encounter between a patient and a healthcare professional caused by the
worsening of the patient’s health is implemented to explain the concept of HDS
and its use in an advanced EHR system. Precision Medicine includes the
discovery of a patient-specific pattern of disease progression, as well as a determination
of the precise therapy for that pattern, and the corresponding personalized
delivery of care [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]. Although EHRs are instrumental across this spectrum, they focus
on personalized healthcare delivery based on the rapidly evolving knowledge
base brought about by advances in genomic medicine.
      </p>
      <p>
        An Internet of Medical Things (IoMT) platform for pervasive healthcare
that ensures interoperability, quality of the detection process, and scalability in
a machine-to-machine-based architecture and provides functionalities for the
processing of high volumes of data, knowledge extraction, and common
healthcare services, was proposed in [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]. The platform uses the semantics described in
OpenEHR for both data quality evaluation and standardization of healthcare data
stored by the association of IoMT devices and observations defined in OpenEHR.
In [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ], the authors had demonstrated the feasibility of a scalable, accurate, and
efficient approach for medical device surveillance using EHRs. They presented
that implant manufacturer and model, implant-related complications, as well as
mentions of post-implant pain can be reliably identified from clinical notes in the
EHR.
      </p>
      <p>
        Three threats from real cloud-based electronic healthcare (eHealth)
systems, i.e., privacy leakage, frequency analysis, and identical data inference had
been identified in [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]. They propose a multi-source order-preserving encryption
(MSOPE) scheme for cloud-based eHealth systems, which enables doctors to
perform privacy-preserving range queries over encrypted EHRs from multiple
patients.
      </p>
      <p>
        The authors in [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ] built an EHR Aggregator (EHRagg) that integrates the
developments made so far to learn automatically how to convert current
information systems into standard systems. With the EHRagg they address the
interoperability and accessibility problem using the same pragmatic approach: instead
of trying to have all the systems agree with the same standard, they propose a
translation between standards, and of systems to any standard, reducing effort
and time. Wireless sensors in the IoT context in contemplation of model solutions
in the field of eHealth were investigated in [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ]. The focus of their work is on
merging the person’s health data collected through wearable and non-wearable
sensors into the formal infrastructure and services within Croatia’s central health
information system. The process encompasses a collection of data and
transforming the data collected into a proper medical format (HL7 or FHIR) to ensure the
data is structured and easy to understand.
      </p>
      <p>
        The authors in [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ] outlined various secondary uses of EHR to give an idea
of how effectively EHR data can be used in different domains such as clinical
research, public health surveillance and clinical audits to provide effective, timely
and quality healthcare facilities to the patients. Data security and patients’
privacy risks related to the secondary uses of EHR especially when EHR data are
transmitted through a network and shared with multiple stakeholders are also
critically studied. Different database models’ appropriateness for integrating
different EHRs functions with different database specifications and workload
scenarios were discussed in [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ]. According to their related works’ analysis, every
database technology offers diverse health care task performance according to this
database’s specification and related workload types.
      </p>
      <p>
        The authors in [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ] describe steps necessary to use the EHR as a tool for
conducting high-quality clinical research. They mention the inadequate or
complete lack of standard data structures in current EHR as a problem in using
pointof-care data for research and examine the changes necessary for reconfiguring
current electronic health records to collect data of sufficient quality to support
the most stringent research methods, namely randomized clinical trials (RCTs).
      </p>
      <p>
        Applications of unsupervised machine learning approach discovering latent
disease clusters and patient subgroups using EHR data were described in [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ].
They utilized Latent Dirichlet Allocation (LDA), an unsupervised probabilistic
generative model in the rubric of topic models, and proposed a novel
unsupervised machine learning approach Poisson Dirichlet Model (PDM).
      </p>
      <p>
        A knowledge-driven framework able to transform disparate data into
knowledge from which actions can be taken to help clinicians and data practitioners in
the complex tasks of extracting valuable knowledge from heterogeneous datasets
is described in [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ]. They describe the application of the framework in the
biomedical domain and show the potential for uncovering patterns that can enable
the explanation of treatment interactions and patient characterization.
      </p>
      <p>
        A tethered PHR that seeks to achieve interoperability by using open-source
standards and their implementation is presented in [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ]. A tethered PHR
application achieves both structural and semantic interoperability to allow data
exchange with external systems such as an EHR easing data integration issues and
improving data quality. The prototyped mobile PHR uses the guidelines narrated
in the HL7 PHR-S FM for its functional requirements, the new HL7 FHIR for
capturing and sharing data and SNOMED for attaching semantics to the captured
data. The primary goal of the prototype is to demonstrate the capability of HL7
FHIR and its features (profile, extensions, and capability standard) to design and
implement an interoperable PHR that aligns with HL7 PHR-S FM. As HL7 FHIR
is a specification, the EHR and mobile PHR leverage the HAPI FHIR, a Java
implementation of the HL7 FHIR. The data captured in the PHR is structured as
FHIR resources and shared in JSON format with the EHR using web services.
According to the conclusion in [
        <xref ref-type="bibr" rid="ref17">17</xref>
        ], cancer genomic information integration into
EHRs could help promote the benefits of patient-centered care. Machine
learning algorithms and CDS software will harness cancer genomic-EHR integration.
They suggest clinicians to be more inclined to let the genomic information in
their patients’ EHRs better guide the decisions they make if it is well integrated.
      </p>
      <p>
        Several EU projects intend to focus healthcare data integration on the
patient, providing patient-centric healthcare data integration cross border through
PHR where the patient is the data owner [
        <xref ref-type="bibr" rid="ref18">18</xref>
        ]. The security issues are considered
from the aspect of the patient and living country of the patient [
        <xref ref-type="bibr" rid="ref19">19</xref>
        ]. The proposed
model is cloud-based cross-border healthcare system based on the PHR concept
with an e-health strategy. The key point is that data collection can be made
sometimes out of hospitals and HIS and perhaps it cannot be connected with EHR and
country of living. This concept demands increasing the e-health and health digital
literacy to be implemented as well as the support of the national and local medical
and healthcare authorities [
        <xref ref-type="bibr" rid="ref18">18</xref>
        ] [
        <xref ref-type="bibr" rid="ref20">20</xref>
        ].
      </p>
      <p>
        Some authors think that healthcare data integration has to be wider and has to
provide wider data integration, for not only data analysis and healthcare
decisionmaking. An integration of healthcare data, medical, omics, sensors data as well
as exposome data to provide data for prediction of the influence of health of
environmental, social, stress factors to risk to health assessment was proposed by
[
        <xref ref-type="bibr" rid="ref21">21</xref>
        ] and [
        <xref ref-type="bibr" rid="ref22">22</xref>
        ].
      </p>
      <p>The Cross4all project model integrates healthcare and medical data from
different sources as EHR, HISs and measurement sensors into PHR as the first stage
towards the integration of patient health data. These data, as well as numerous
biological omics and exposome data and data obtained from wearables, are
considered and stored on the cloud following the required data security and privacy
standards.
3</p>
    </sec>
    <sec id="sec-3">
      <title>Privacy and rersonal health data of patients</title>
      <p>
        Providing patients with proper healthcare information and health facilities at a
low cost has always been a great challenge for health service providers. It includes
health monitoring in- and out-of-hospital conditions for older people and patients
who need supervision. Recent advances in wireless sensor technology envisage
new types of ubiquitous healthcare systems [
        <xref ref-type="bibr" rid="ref23 ref24">23, 24</xref>
        ]. These systems provide
permanent monitoring of patients, even during their normal daily activities,
without compromising their quality of life, enabling the development of
patientcentric pervasive environments in addition to the hospital-centric ones [
        <xref ref-type="bibr" rid="ref19">19</xref>
        ]. Such
systems will enable healthcare personnel to timely access, review, and update
and send patient EHR from wherever they are, whenever they want [
        <xref ref-type="bibr" rid="ref21">21</xref>
        ]. Some of
those systems are based on open platform interfacing to a wide variety of sensors,
collecting and storing the data in a server repository, and making the available
EHR data applications through a documented API [
        <xref ref-type="bibr" rid="ref25">25</xref>
        ].
      </p>
      <p>
        There are several architectural models for building this kind of personal
healthcare system [
        <xref ref-type="bibr" rid="ref26">26</xref>
        ]. Pervasive health provides technologies that help citizens
participate more closely in their healthcare [
        <xref ref-type="bibr" rid="ref24">24</xref>
        ]. They should provide flexibility
in patients who lead an active everyday life with work, family, and friends [
        <xref ref-type="bibr" rid="ref27">27</xref>
        ].
However, these systems do not consider the collaborative value that can be
provided with matching gathered data. Dataflow of patients with the same
diagnoses can be provided directly or as grouped statistical summaries. It enables the
exchange of patients’ experiences by using the activities that other patients have
taken.
      </p>
      <p>In the process of designing a healthcare system, the following points about
Electronic PHR data should be considered:
1. Data needs to be actionable to patients, policymakers, and health care
providers in order to help them make better decisions.
2. “Everyday” data needs to be considered and can be as valuable as lab
tests in its impact on their health outcomes.
3. Patients and healthcare providers need to look at their relationship as
a collaboration, which requires a new definition of the doctor-patient
relationship.
4. Technology offers opportunities, but it is not the silver bullet. It cannot
be intrusive; it needs to be a part of an individual’s life.</p>
      <p>A simple overview of the typical distributed healthcare system model is
presented in Fig. 1. The system is deployed over three primary pillars:
1. The first pillar consists of the bio network (implemented from various
body sensors) and mobile application that collects users’ biodata during
various physical activities (e.g., walking, running, and cycling).
2. The second pillar is presented by the social network implemented as a web
portal, enabling different collaboration within the end-user community.
3. The third pillar enables interoperability with the primary/secondary
health care information systems, which can be implemented in the
clinical centers and different policymaker institutions.</p>
      <p>Communication between the first and third pillars of the model is determined
by communication between patients and healthcare centers. The patient has
24hour access to medical personnel with the possibility to make an emergency call.
The medical staff monitors the patient’s medical condition remotely, reviewing
the medical data and responding to the patient by suggesting the most suitable
therapy. The medical personnel can also send patients various notifications (e.g.,
tips and suggestions) regarding his/her health condition.</p>
      <p>The second and third pillars can exchange data and information regarding
the larger group of patients by any significant indicator (region, time, sex, type
of activities), which can be later used for research, policy recommendations, and
medical campaign suggestions.</p>
      <p>
        One of the most critical issues in the system is information validity and
confirmation. We can divide system information validity into three categories [
        <xref ref-type="bibr" rid="ref28">28</xref>
        ].
Most reliable information is information that originates from the medical
databases, clinical centers, and sometimes biosensors depending on their usage
factors. Less reliable information is information generated from Social networks.
This information can increase its reliability if confirmed by clinical centers’
medical records. Information from personal profiles (age, weight, height, diagnosis
entered by end-user) is the third category of information (unreliable information).
An increase of validation of this information can be done by comparing them
with average results using a social network or by confirming them with the
medical records coming from healthcare institutions.
      </p>
      <p>The categorization of the validity of the information can be used to
determine the validity of notifications created within the system. It is essential because
it affects the users’ decision whether to respect the notification or not. Every user
can determine what information can be private or public. To obtain medical
support, the user has to agree to share personal information with clinical centers and
medical databases, whose data are protected. According to the user agreement
policy, data information would be exchanged through the system.</p>
      <p>Many healthcare researchers are interested in collecting medical sensor data.
As that data may contain many personal facts, many patients are not willing to
reveal them.</p>
      <p>The sensor network consists of a variety of sensors with a variety of
interfaces. A medical provider can set a cloud service, by research organizations, by
government-run medical databases, or by private companies providing additional
services. The fog layer is the bridge between the sensor network and the cloud.
The e-health gateway has sufficient computing capabilities for simple data
processing, but its primary role is data aggregation and communication. Depending
on the path to the cloud instances, some nodes carry data that has been filtered
to enhance privacy. In contrast, other nodes carry data with more physiological
data, which might be needed for health monitoring by health care providers or
emergency services.
4</p>
    </sec>
    <sec id="sec-4">
      <title>Cross4all project model of patient’s healthcare data</title>
      <p>The Cross4all project integration model has the patient’s centric concept (Fig.
2). The patients who will have their PHR in the cloud system can store their data
and provide privacy and security, but can temporarily grant access to their data
to doctors who are also registered in the system. Sensors’ data connected with
measuring vital signs of life of patients as healthcare data, are also acquired in
order to provide data in their PHR. EHR data also can be taken into consideration
by an authorized person without direct connection to PHR by the medical persons
or indirectly, from the patient, as scanned unstructured data, also accessible by
doctors. Labs and biometrics reports can also be in PHR as scanned unstructured
documents optionally.</p>
      <p>Medical and omics accessible data can be connected with PHR and related
to diseases. Some data can be provided by clinicians and connected with
phenotype, metabolic and genetic data and related data with patient’s disease. It means
that some recommendations for the patient can be done according to doctors’
insights with a combination of PHR and other available data for the patient. In
addition, some soft data related to healthcare data, optionally, can be provided
and integrated into PHR, as environmental, social media and other data named as
exposome data.</p>
      <p>This model can have the potential for healthcare risk assessment for disease
taken from PHR and environmental and location connected data. The risk
assessment demands the usage of complex algorithms, AI and medical knowledge as
well as disease connected data analysis.</p>
      <p>
        Standardization is provided to prevent malicious system misusing. It has to
enable security access protocols, intrusion detection and prevention techniques,
providing SIEM systems, with audit logs of the users and administrator activities [
        <xref ref-type="bibr" rid="ref19">19</xref>
        ].
      </p>
      <p>The integrated model of heterogeneous data into electronic PHR rely on a
high level of security and privacy and provide adequate access to data for the
appropriate user. In the model, the first step to proper user orientation to the
appropriate resource is the Authentication and Authorization sub-system (AAA -
Authentication, Authorization and Accounting), for which Keycloak server is used
to check the type, credential and the affiliation of user access. The first check for
secure access is by verifying the authentication - username and password (which
can enter an additional way to verify authentication using a short-term token) to
check if the user has the right to access. If it is authenticated, the authorization
check is performed, i.e. the role of the user is determined, for example, patient,
doctor or pharmacist. The last step in the AAA framework is user accounting,
which measures the resources the user consumes during access. This may include
the measurement of system time or the amount of data that the user sent and/
or received during the session. It also deals with statistical data for sessions and
resources using information; it is used for authorization control, billing, trend
analysis, resources usage and capacity planning activities.</p>
      <p>After this first level of security control, the user is redirected to the
appropriate control server in the appropriate domain (here according to the country of
origin or affiliation). Distribution should be transparent to users, i.e. the system
should have only one unique and integral location for the API URL to be used
by applications and end-user integrations, regardless of the origin of the request.
This configuration is possible with two or more servers located in each country,
connected to the health-data integration hub (it could be the World Health
Organization, for instance) and end-user authentication and authorization requests.
Applications are filtered and processed according to the domain of origin of their
username, so it is redirected to the appropriate Keycloak server from each
country for further processing. Upon completion of the authentication and
authorization procedure, the client receives an authenticated token that can be used to
access the API endpoints and through them access the EHR data.</p>
      <p>
        Because user access data is disaggregated based on affiliation, specifically
on the user’s country of origin, this user identification and authorization data is
stored on the federal (shared) server in the respective country and is used for
authentication and authorization purpose. The user can be assigned the appropriate
role: patient (the most important of which are the role of the patient who owns
the PHR data), the role of the physician who can access and generate additional
PHR data, and the role of the pharmacist who can access only parts of PHR data
related to e-prescription services. Role-based access control for accessing PHR
data (or only part of PHR data) is defined in user roles. They are also defined in
the Keycloak SSO servers and thus the user gets an authenticated token, which
he uses, in the further process. Subsystems that allow routing/redirection to
appropriate API endpoints follow these rules, check the authorization token, and
grant or deny access to the required data. With this approach, authentication rules
can be changed even when the system is in production, and additional
segmentation rules for data access can be implemented. Fig. 3 presents Visual Notation for
OWL Ontologies (VOWL) used in the model, according to Fast Healthcare
Interoperability Resources (FHIR), as a part of PHR software, which integrated EHR.
The pandemic situation and the increasing number of patients with chronic
diseases demand quick access to patient’s healthcare and medical data. Many
problems appear from the lack of healthcare patient’s information, especially when
patients with chronic diseases and their treatments are considered. This is very
important when patients change the place of living and the medical personnel do
not have their data available. The efforts for healthcare data integration until now
are mostly intended for high-level decision-makers and data are depersonalized.
For this reason, the model is PHR-centric, which integrates data from the PHR
of the patient according to HL7 standard. HL7 has developed the FHIR as a
new foundation to achieve interoperability. The concept of this model takes into
account security and privacy issues, specific for PHR, health and medical-related
data and personal data [
        <xref ref-type="bibr" rid="ref29">29</xref>
        ]. The model can integrate sensors’ data, exposome and
omics data, intended for accurate healthcare risk assessment of the patient, using
many public environmental data, atmospheric electromagnetic fields data, social
media and other valuable data.
      </p>
      <p>In this model, the patient is the main actor in the system. The patient who
has their PHR can temporarily grant access to their data to the selected medical
staff and can have the possibility to use PHR and mobile applications to gather
healthcare data in their PHR. The medical staff can use mobile applications
connected to the specific measurement sensors for professionals to provide a vital
signs measurement for the particular patient, acquired and saved in the patient’s
PHR securely and privately, according to the country’s data protection law. In the
model, PHR is related to data gained from specific medical devices and sensors,
from the patient’s EHR as scanned unstructured data, omics data connected with
patient’s chronic diseases and social media data. These integrated data have to
provide healthcare risk assessment connected with exposome data from
environmental databases, connected with the living location of the patient. The
implementation of such complex project pointed that such model demands high level
of digital healthcare literacy and competency of the patients. As a direction for
further works, the model should be validated with exposome data and some
algorithms for risk assessment have to be assessed for particular chronic diseases.
6</p>
    </sec>
    <sec id="sec-5">
      <title>Acknowledgement</title>
      <p>Part of the work presented in this paper has been carried out in the framework
of the project “Cross-border initiative for integrated health and social services
promoting safe ageing, early prevention and independent living for all
(Cross4all)”, which is implemented in the context of the INTERREG IPA Cross
Border Cooperation Programme CCI 2014 TC 16 I5CB 009 and co-funded by the
European Union and national funds of the participating countries.</p>
    </sec>
  </body>
  <back>
    <ref-list>
      <ref id="ref1">
        <mixed-citation>
          1.
          <string-name>
            <surname>Silvestri</surname>
            <given-names>S.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Esposito</surname>
            <given-names>A.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Gargiulo</surname>
            <given-names>F.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Sicuranza</surname>
            <given-names>M.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Ciampi</surname>
            <given-names>M.</given-names>
          </string-name>
          , De Pietro G.,
          <article-title>A Big Data Architecture for the Extraction</article-title>
          and
          <source>Analysis of EHR Data</source>
          ,
          <source>2019 IEEE World Congress on Services (SERVICES) 978-1-7281-3851-0</source>
          /19/.
        </mixed-citation>
      </ref>
      <ref id="ref2">
        <mixed-citation>
          2.
          <string-name>
            <surname>Jayaratne</surname>
            <given-names>M.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Nallaperuma</surname>
            <given-names>D.</given-names>
          </string-name>
          , Daswin de Silva, Alahakoon D.,
          <string-name>
            <surname>Devitt</surname>
            <given-names>B.</given-names>
          </string-name>
          ,
          <article-title>A data integration platform for patient-centered e-healthcare and clinical decision support</article-title>
          ,
          <source>Future Generation Computer Systems · September</source>
          <year>2018</year>
          , at: https://www.researchgate.net/publication/327924847.
        </mixed-citation>
      </ref>
      <ref id="ref3">
        <mixed-citation>
          3.
          <string-name>
            <surname>Goodrum</surname>
            <given-names>H.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Roberts</surname>
            <given-names>K.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Bernstam</surname>
            ,
            <given-names>E. V.</given-names>
          </string-name>
          ,
          <article-title>Automatic classification of scanned electronic health record documents</article-title>
          ,
          <source>International Journal of Medical Informatics</source>
          ,
          <volume>144</volume>
          ,
          <year>2020</year>
          104302.
        </mixed-citation>
      </ref>
      <ref id="ref4">
        <mixed-citation>
          4.
          <string-name>
            <surname>Serbanati L. D.</surname>
          </string-name>
          ,
          <article-title>Health digital state and Smart EHR systems</article-title>
          .
          <source>Informatics in Medicine Unlocked</source>
          ,
          <volume>21</volume>
          , (
          <year>2020</year>
          ),
          <fpage>100494</fpage>
          .
        </mixed-citation>
      </ref>
      <ref id="ref5">
        <mixed-citation>
          5.
          <string-name>
            <surname>Sitapati</surname>
            <given-names>A.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Kim</surname>
            <given-names>H.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Berkovich</surname>
            <given-names>B</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Marmor</surname>
            <given-names>R.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Singh</surname>
            <given-names>S.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>El-Kareh</surname>
            <given-names>R.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Clay</surname>
            <given-names>B</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Ohno-Machado</surname>
            <given-names>L.</given-names>
          </string-name>
          , Integrated Precision Medicine:
          <article-title>The Role of Electronic Health Records in Delivering Personalized Treatment</article-title>
          ,
          <source>Wiley Interdiscip Rev Syst Biol Med. Author manuscript; available in PMC 2018 May</source>
          <volume>01</volume>
          .
        </mixed-citation>
      </ref>
      <ref id="ref6">
        <mixed-citation>
          6.
          <string-name>
            <surname>Rubí</surname>
            <given-names>J. N. S.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Gondim</surname>
            <given-names>P. R. L.</given-names>
          </string-name>
          ,
          <source>IoMT Platform for Pervasive Healthcare Data Aggregation, Processing, and Sharing Based on OneM2M and OpenEHR</source>
          , Sensors,
          <volume>19</volume>
          (
          <issue>19</issue>
          ),
          <fpage>4283</fpage>
          .
        </mixed-citation>
      </ref>
      <ref id="ref7">
        <mixed-citation>
          7.
          <string-name>
            <surname>Callahan</surname>
            <given-names>A.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Fries</surname>
            <given-names>J. A.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Ré</surname>
            <given-names>C.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Huddleston</surname>
            <given-names>J.I.</given-names>
          </string-name>
          ,
          <string-name>
            <given-names>J. Giori N.J.</given-names>
            ,
            <surname>Delp</surname>
          </string-name>
          <string-name>
            <given-names>S.</given-names>
            ,
            <surname>Shah</surname>
          </string-name>
          <string-name>
            <surname>N. H.</surname>
          </string-name>
          ,
          <article-title>Medical device surveillance with electronic health records</article-title>
          ,
          <source>npj Digital Medicine 2019</source>
          <volume>2</volume>
          :
          <issue>94</issue>
          , https:// doi.org/10.1038/s41746-019-0168-z
        </mixed-citation>
      </ref>
      <ref id="ref8">
        <mixed-citation>
          8. JLiang J. , Qin
          <string-name>
            <given-names>Z.</given-names>
            ,
            <surname>Xiao</surname>
          </string-name>
          <string-name>
            <given-names>S.</given-names>
            ,
            <surname>Zhang</surname>
          </string-name>
          <string-name>
            <given-names>J</given-names>
            ,
            <surname>Yin</surname>
          </string-name>
          <string-name>
            <given-names>H</given-names>
            ,
            <surname>Li</surname>
          </string-name>
          <string-name>
            <surname>K</surname>
          </string-name>
          ,
          <article-title>Privacy-preserving range query over multisource electronic health records in public clouds</article-title>
          ,
          <source>Journal of Parallel and Distributed Computing</source>
          , Volume
          <volume>135</volume>
          ,
          <year>January 2020</year>
          , pp.
          <fpage>127</fpage>
          -
          <lpage>139</lpage>
          .
        </mixed-citation>
      </ref>
      <ref id="ref9">
        <mixed-citation>
          9.
          <string-name>
            <surname>Prados-Suárez</surname>
            <given-names>B.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Molina</surname>
            <given-names>C.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Pena-Yañez</surname>
            ,
            <given-names>C.</given-names>
          </string-name>
          ,
          <article-title>Providing an Integrated Access to HER Using Electronic Health RecordsAggregators, Digital Personalized Health</article-title>
          and
          <string-name>
            <surname>MedicineL.B. PapeHaugaard</surname>
          </string-name>
          et al. (Eds.)
          <article-title>© 2020 European Federation for Medical Informatics (EFMI) and</article-title>
          IOS Press, doi:10.3233/SHTI200191.
        </mixed-citation>
      </ref>
      <ref id="ref10">
        <mixed-citation>
          10.
          <string-name>
            <surname>Koren</surname>
            <given-names>A.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Jurčević</surname>
            <given-names>M.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Huljenić</surname>
            <given-names>D</given-names>
          </string-name>
          , “
          <article-title>Requirements and Challenges in Integration of Aggregated Personal Health Data for Inclusion into Formal Electronic Health Records (EHR),”2nd International Colloquium on Smart Grid Metrology (SMAGRIMET), Split</article-title>
          , Croatia,
          <year>2019</year>
          , pp.
          <fpage>1</fpage>
          -
          <lpage>5</lpage>
          ,
          <year>2019</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref11">
        <mixed-citation>
          11.
          <string-name>
            <surname>Shah</surname>
            <given-names>S. M.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Khan</surname>
            <given-names>R. A.</given-names>
          </string-name>
          ,
          <source>Secondary Use of Electronic Health Record: Opportunities and Challenges</source>
          , arXiv:
          <year>2001</year>
          .
          <article-title>09479v1 [cs</article-title>
          .
          <source>CY] 26 Jan</source>
          <year>2020</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref12">
        <mixed-citation>
          12.
          <string-name>
            <surname>Gamal</surname>
            <given-names>A.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Barakat</surname>
            <given-names>S.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Rezk</surname>
            <given-names>A.</given-names>
          </string-name>
          ,
          <article-title>Standardized Electronic Health Record Data Modeling and Persistence: A Comparative Review</article-title>
          .
          <source>Journal of biomedical informatics</source>
          ,
          <volume>103670</volume>
          ,
          <year>2020</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref13">
        <mixed-citation>
          13.
          <string-name>
            <surname>Bertagnolli M. M</surname>
            , Anderson
            <given-names>B.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Quina</surname>
            <given-names>A.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Piantadosi</surname>
            <given-names>S.,</given-names>
          </string-name>
          <article-title>The electronic health record as a clinical trials tool: Opportunities and challenges</article-title>
          ,
          <source>Clinical Trials 1-6</source>
          ,
          <year>2020</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref14">
        <mixed-citation>
          14.
          <string-name>
            <surname>Wanga</surname>
            <given-names>Y.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Zhao</surname>
            <given-names>Y.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Therneau</surname>
            <given-names>T. M.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Atkinson</surname>
            <given-names>E. J.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Tafti</surname>
            <given-names>A. P.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Zhang</surname>
            <given-names>N.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Amni</surname>
            <given-names>S.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Limper</surname>
            <given-names>A. H.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Khoslae</surname>
            <given-names>S.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Liu</surname>
            <given-names>H.,</given-names>
          </string-name>
          <article-title>Unsupervised machine learning for the discovery of latent disease clusters and patient subgroups using electronic health records</article-title>
          .
          <source>Journal of biomedical informatics</source>
          ,
          <volume>102</volume>
          ,
          <fpage>103364</fpage>
          ,
          <year>2020</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref15">
        <mixed-citation>
          15.
          <string-name>
            <surname>Vidal</surname>
            <given-names>M. E.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Endris</surname>
            <given-names>K. M.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Jazashoori</surname>
            <given-names>S.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Sakor</surname>
            ,
            <given-names>Sakor A.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Rivas</surname>
            ,
            <given-names>A.</given-names>
          </string-name>
          <article-title>Transforming Heterogeneous Data into Knowledge for Personalized Treatments-A Use Case</article-title>
          .
          <source>Datenbank-Spektrum, part of Springer Nature</source>
          <year>2019</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref16">
        <mixed-citation>
          16.
          <string-name>
            <surname>Saripalle</surname>
            <given-names>R</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Runyan</surname>
            <given-names>C</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Russell</surname>
            <given-names>M</given-names>
          </string-name>
          ,
          <article-title>Using HL7 FHIR to achieve interoperability in patient health record</article-title>
          .
          <source>J Biomed Inform</source>
          .
          <year>2019</year>
          Jun;
          <volume>94</volume>
          :
          <fpage>103188</fpage>
          .
        </mixed-citation>
      </ref>
      <ref id="ref17">
        <mixed-citation>
          17.
          <string-name>
            <surname>Warner</surname>
            <given-names>J. L.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Jain</surname>
            <given-names>S. K.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Levy</surname>
            <given-names>M.A.</given-names>
          </string-name>
          ,
          <article-title>Integrating cancer genomic data into electronic health records, Warner et al</article-title>
          . Genome
          <string-name>
            <surname>Medicine</surname>
          </string-name>
          (
          <year>2016</year>
          )
          <volume>8</volume>
          :
          <fpage>113</fpage>
          .
        </mixed-citation>
      </ref>
      <ref id="ref18">
        <mixed-citation>
          18.
          <string-name>
            <surname>Snezana</surname>
            <given-names>S</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Kilintzis</surname>
            <given-names>V.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Jakimovski</surname>
            <given-names>B.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Jolevski</surname>
            <given-names>I.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Beredimas</surname>
            <given-names>N.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Mourouzis</surname>
            <given-names>A.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Corbev</surname>
            <given-names>I.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Chouvarda</surname>
            <given-names>I.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Maglaveras</surname>
            <given-names>A.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Trajkovik</surname>
            <given-names>V.</given-names>
          </string-name>
          ,
          <article-title>Cloud Based Personal Health Records Data Exchange in the Age of IoT: The Cross4all Project</article-title>
          . In: Dimitrova V.,
          <string-name>
            <surname>Dimitrovski</surname>
            <given-names>I</given-names>
          </string-name>
          . (
          <article-title>eds) ICT Innovations 2020</article-title>
          .
          <article-title>Machine Learning and Applications</article-title>
          .
          <source>ICT Innovations 2020. Communications in Computer and Information Science</source>
          , vol
          <volume>1316</volume>
          . Springer, Cham.
        </mixed-citation>
      </ref>
      <ref id="ref19">
        <mixed-citation>
          19.
          <string-name>
            <surname>Savoska</surname>
            <given-names>S.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Jolevski</surname>
            <given-names>I.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Ristevski</surname>
            <given-names>B.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Blazeska-Tabakovska</surname>
            <given-names>N.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Bocevska</surname>
            <given-names>A.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Jakimovski</surname>
            <given-names>B.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Chorbev</surname>
            <given-names>I.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Kilintzis</surname>
            <given-names>V.</given-names>
          </string-name>
          ,
          <article-title>Design of Cross Border Healthcare Integrated System and its Privacy and Security Issues</article-title>
          , In Proceedings of Computer and Communications Engineering, Workshop on Information Security, 9th Balkan Conference in Informatics, Volume
          <volume>13</volume>
          ,
          <issue>2</issue>
          /2019, Pp.
          <fpage>58</fpage>
          -
          <lpage>64</lpage>
        </mixed-citation>
      </ref>
      <ref id="ref20">
        <mixed-citation>
          20.
          <string-name>
            <surname>Savoska</surname>
            <given-names>S.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Jolevski</surname>
            <given-names>I.</given-names>
          </string-name>
          ,
          <article-title>Architectural Model of e-health PHR to Support the Integrated Crossborder Services</article-title>
          ,
          <source>In proceedings of ISGT conference</source>
          <year>2018</year>
          , pp.
          <fpage>42</fpage>
          -
          <lpage>49</lpage>
          , Sofia,
          <year>2019</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref21">
        <mixed-citation>
          21.
          <string-name>
            <surname>Savoska</surname>
            <given-names>S.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Ristevski</surname>
            <given-names>B.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Blazheska-Tabakovska N. Jolevski</surname>
            <given-names>I</given-names>
          </string-name>
          .
          <article-title>Towards Integration Exposome Data and Personal Health Records in the Age of IoT</article-title>
          .
          <source>In: 11th ICT Innovations Conference</source>
          <year>2019</year>
          ,
          <fpage>17</fpage>
          -
          <lpage>19</lpage>
          October, Ohrid, Republic of Macedonia.pp.
          <fpage>237</fpage>
          -
          <lpage>246</lpage>
          ,
          <year>2019</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref22">
        <mixed-citation>
          22.
          <string-name>
            <surname>Barouki</surname>
            <given-names>R.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Audouze</surname>
            <given-names>K.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Coumoul</surname>
            <given-names>X.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Demenais</surname>
            <given-names>F.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Gauguier</surname>
            <given-names>D.</given-names>
          </string-name>
          ,
          <article-title>Integration of the human exposome with the human genome to advance medicine</article-title>
          .
          <source>Biochimie, Elsevier</source>
          ,
          <year>2018</year>
          ,
          <volume>152</volume>
          , pp.
          <fpage>155</fpage>
          -
          <lpage>158</lpage>
          .
          <fpage>10</fpage>
          .1016/j.biochi.
          <year>2018</year>
          .
          <volume>06</volume>
          .023. hal-
          <fpage>02196327</fpage>
        </mixed-citation>
      </ref>
      <ref id="ref23">
        <mixed-citation>
          23.
          <string-name>
            <surname>Znati</surname>
            <given-names>T.</given-names>
          </string-name>
          , “
          <article-title>On the challenges and opportunities of pervasive and ubiquitous computing in health care”</article-title>
          .
          <source>Proceedings of the IEEE International Conference on Pervasive Computing and Communications - PerCom</source>
          <year>2005</year>
          ,
          <string-name>
            <given-names>Kauai</given-names>
            <surname>Island</surname>
          </string-name>
          <string-name>
            <surname>HI</surname>
          </string-name>
          , USA:
          <fpage>396</fpage>
          .
        </mixed-citation>
      </ref>
      <ref id="ref24">
        <mixed-citation>
          24.
          <string-name>
            <surname>Ahamed</surname>
            <given-names>S. I.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Haque</surname>
            <given-names>M. M.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Stamm</surname>
            <given-names>K.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Khan</surname>
            <given-names>A.J.</given-names>
          </string-name>
          , “
          <article-title>Wellness assistant: a virtual wellness assistant using pervasive computing”</article-title>
          ,
          <source>Proc. Symposium on Applied Computing</source>
          , USA: ACM,
          <year>2007</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref25">
        <mixed-citation>
          25.
          <string-name>
            <surname>Blount</surname>
            <given-names>M.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Batra</surname>
            <given-names>V. M.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Capella</surname>
            <given-names>A. N.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Ebling</surname>
            <given-names>M. R.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Jerome</surname>
            <given-names>W. F.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Martin</surname>
            <given-names>S. M.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Nidd</surname>
            <given-names>M.</given-names>
          </string-name>
          ,.
          <string-name>
            <surname>Niemi</surname>
            <given-names>M. R.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Wright</surname>
            <given-names>S. P.</given-names>
          </string-name>
          , “
          <article-title>Remote healthcare monitoring using Personal Care Connect”</article-title>
          ,
          <source>IBM Systems Journal</source>
          , vol
          <volume>46</volume>
          (
          <issue>1</issue>
          ),
          <year>2007</year>
          , pp
          <fpage>95</fpage>
          -
          <lpage>113</lpage>
          .
        </mixed-citation>
      </ref>
      <ref id="ref26">
        <mixed-citation>
          26.
          <string-name>
            <surname>Shopov</surname>
            <given-names>M.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Spasov</surname>
            <given-names>G.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Petrova</surname>
            <given-names>G.</given-names>
          </string-name>
          ,
          <article-title>“Architectural models for realization of Web-based Personal Health Systems”</article-title>
          ,
          <source>Proc. International Conference on Computer Systems and Technologies and Workshop for PhD Students in Computing, USA: ACM</source>
          ,
          <year>2009</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref27">
        <mixed-citation>
          27.
          <string-name>
            <surname>Ballegaard</surname>
            <given-names>S. A.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Hansen</surname>
            <given-names>T. R.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Kyng</surname>
            <given-names>M.</given-names>
          </string-name>
          , “
          <article-title>Healthcare in everyday life: designing healthcare services for daily life”</article-title>
          ,
          <source>Proc. Conference on Human Factors in Computing Systems, USA: ACM</source>
          ,
          <year>2008</year>
          , pp.
          <fpage>1807</fpage>
          -
          <lpage>1816</lpage>
          .
        </mixed-citation>
      </ref>
      <ref id="ref28">
        <mixed-citation>
          28.
          <string-name>
            <surname>Kotevska</surname>
            <given-names>O.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Vlahu-Gjorgievska</surname>
            <given-names>E.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Trajkovik</surname>
            <given-names>V.</given-names>
          </string-name>
          ,
          <string-name>
            <surname>Koceski</surname>
            <given-names>S.</given-names>
          </string-name>
          , “
          <article-title>Towards a Patient-Centered Collaborative Health Care System Model”</article-title>
          ,
          <source>4th IEEE International Conference on Computer Science and Information Technology (IEEE ICCSIT</source>
          <year>2011</year>
          ), Chengdu, China, June 10-12,
          <year>2011</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref29">
        <mixed-citation>
          29.
          <string-name>
            <surname>Ristevski</surname>
            ,
            <given-names>B.</given-names>
          </string-name>
          , &amp;
          <string-name>
            <surname>Savoska</surname>
            ,
            <given-names>S.</given-names>
          </string-name>
          ,
          <article-title>Healthcare and medical Big Data analytics</article-title>
          .
          <source>Applications of Big Data in Healthcare: Theory and Practice</source>
          ,
          <volume>85</volume>
          ,
          <year>2021</year>
          .
        </mixed-citation>
      </ref>
    </ref-list>
  </back>
</article>