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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Development of an E-mental Health Infrastructure for Supporting Interoperability and Data Analysis</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Fazle Rabbi</string-name>
          <email>fFazle.Rabbi@hvl.no</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Yngve Lamo</string-name>
          <email>Yngve.Lamo@hvl.nog</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Western Norway University of Applied Sciences</institution>
          ,
          <addr-line>Bergen</addr-line>
          ,
          <country country="NO">Norway</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>Digital technology plays an increasingly important role in addressing the challenges faced by health and care services such as rising costs, changing demographics, shortage of healthcare professionals. eHealth is the use of information and communication technologies (ICT) for healthcare systems which helps patients and healthcare providers work together to ensure faster, safer and better care. eHealth strengthen the use of ICT in health development through a range of services or systems including electronic health record, clinical decision support system, health informatics, self-monitoring healthcare devices, personalized medicine. This paper presents an eHealth infrastructure for E-mental health which is under development. The infrastructure is being designed to provide internet based interventions and support for interoperability and data analysis.</p>
      </abstract>
      <kwd-group>
        <kwd>healthcare systems</kwd>
        <kwd>internet of things</kwd>
        <kwd>process mining</kwd>
        <kwd>machine learning</kwd>
        <kwd>HL7 FHIR</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>
        Today's vast amount of medical data need to be integrated and accessed
intelligently to support better healthcare delivery. Interoperability in healthcare can
bring together partners and facilitate knowledge sharing which can potentially
create new networks of knowledge. Delivering context relevant clinical
information enables decision making through healthcare data analysis. By measuring
and monitoring processes digitally, we can compare data more easily. Such
insight facilitates streamlined work ows, greater e ciency and improved patient
care. Systematic analysis of healthcare data can help to detect patterns so that
healthcare providers can optimize their resource allocation and clinicians can
conduct treatments to individuals and project better health outcomes.
According to WHO a mental health information system should enable managers and
service providers to make well-informed decisions that improve the quality of
care [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ]. To improve the e ectiveness and e ciency of mental health services,
mental health information systems go through the following essential stages:
{ Collection : Data collection from source
{ Processing : movement of data from the source
{ Analysis : examination and study of the raw data
{ Dissemination : communication of the results of the analysis
{ Use : utilization of the results of the analysis for service improvement,
planning, development and evaluation.
      </p>
      <p>
        In this paper, we give an overview of an E-mental health infrastructure that
facilitates the development of mental health information systems. In many
developed countries, majority of their citizens use public healthcare services. To
support a variety of healthcare service providers, these healthcare systems
often use a large number of software applications. For collecting and processing
healthcare data from various sources we require healthcare interoperability. The
term `interoperability' refers to the ability of di erent information systems to
exchange information and understand the semantic of information. Healthcare
interoperability is very essential to reduce the processing time that is required
for the conversions of healthcare information originated by di erent healthcare
providers and/or systems. It is considered as one of the biggest challenge in
today's healthcare systems due to the fact that healthcare systems are
inherently complex and there are many players involved in the healthcare industry.
There has been a lot of initiatives to address healthcare interoperability over
the past decade. HL7 [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ] is an international community who is involved in the
development of a set of international standards, guidelines and methodologies
for sharing healthcare information among healthcare providers. These standards
are referred to as HL7 standards. HL7 FHIR (Fast healthcare Interoperability
Resources) [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ] is the latest standard developed by HL7 for exchanging healthcare
information with a main focus on implementation. It provides a number of
resource types which are the building blocks for exchanging healthcare data. Any
healthcare information that needs to be exchanged among organizations should
be speci ed as FHIR resources. The FHIR standard is suitable to integrate
healthcare applications across organizations, medical devices, and also mobile
healthcare applications. FHIR resources utilize standard terminologies from
ontologies which provide semantic interoperability. Currently we are developing
an interoperability healthcare platform based on HL7 FHIR in collaboration
with Helse Vest ICT [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ], a large IT service provider in Western Norway. The
infrastructure development is partly supported by the `Intromat' project [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ].
      </p>
      <p>There is a great need for doing research in health service improvement to
provide the best care possible to the patients with limited resources. Research
related to health service improvement needs to undertake many complex tasks
such as root cause analysis, capture information from previous steps into a simple
document and study the variability of a large number of patient population. It
is challenging to accomplish these tasks and therefore we require techniques and
tool support. For the examination and study of healthcare information we use
data mining techniques. Data mining techniques provide deeper insights into
patients health by analyzing historical healthcare information including patients
diet, appointments, exercise, lab results, vital signs, prescriptions, treatments,
allergies, etc. Data mining techniques such as process mining in healthcare brings
the opportunity to learn from patients healthcare information including children,
women, elderly, patients with co-morbidity and the results can be utilized for
optimizing healthcare resources and the improvement of health service delivery.</p>
      <p>We need to disseminate the analysis results to a diverse group of people in the
healthcare system. Healthcare managers, analysts and clinicians need to
visualize healthcare processes across disciplines to investigate the common pathways
of patients. Identifying common pathways for patients ow in healthcare systems
is complex as we need to deal with a variety of patients group. While analyzing
common pathways for patients, di erent context need to be setup to focus on
different group of patients and visualize their care ows. For instance, the manager
of the pediatrics department in a hospital would be interested to look at the ow
of patients' admission at the children clinics and other departments to make a
better planning of resource distribution; a clinician would be interested to
investigate the common pathways of patients with mental and behavioral disorders
to extract knowledge about concurrent common mental disorders; an analyst
may be interested to investigate the e ciency of a new planning strategy.
Resources in healthcare may include time, money, facilities, equipment, people and
competences. Proper resource planning needs to be carried out in healthcare to
ensure that healthcare providers are not overloaded with work, patients are not
waiting too long to get services, and the overall cost of healthcare is optimized.
In our approach, we disseminate the results of care ow analysis to healthcare
professionals for service quality improvement.
2</p>
    </sec>
    <sec id="sec-2">
      <title>System architecture</title>
      <p>
        There are a variety of health service providers in a healthcare system and the
healthcare data are often siloed away from other data. Data silos is not only the
problem in a healthcare setting but di erent standards are being followed by
di erent health facilities to code diagnosis, lab test results, medical procedures
and drugs. Variety of data models of di erent service providers are making data
analysis challenging. To address this issue, it is therefore important to create
an infrastructure for ad-hoc exploration of large collections of data. Such an
infrastructure needs to be exible and scalable yet supporting suitable format for
decision making. We envision a healthcare information system that provides
access to information from various healthcare providers as well as patients personal
healthcare devices and/or applications. Availability of information from patients
personal healthcare devices can potentially be used to detect complicated
problems correctly in their early stage and monitor the e ects of treatment. For
instance, bipolar disorder can be di cult to diagnose and according to a study
published in Psychiatry, around 69 percent of bipolar disorder cases are
misdiagnosed [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ]. Analyzing patients personal healthcare information can be used
to identify periods of mania and depression. Correct identi cation of depressive
and one manic or hypomanic episodes are important factors for the diagnosis of
bipolar disorder. However, the integration of personal healthcare devices in the
mainstream treatment process will require the use of healthcare standards.
      </p>
      <p>We chose to use HL7 FHIR as it allows us to integrate healthcare
information collected from several sources. Although HL7 FHIR provides a suitable
way to harmonize healthcare information, it does not provide any sophisticated
visualization technique to get an overview of patients health or administrative
information. In our approach, we apply process mining techniques for extracting
an overall picture of healthcare information from various contextual view and
from di erent level of abstraction and utilize machine learning techniques to
constantly monitor patients condition and raise alarms.</p>
      <p>Mobile and VR apps
Wellness and fitness</p>
      <p>devices
Remote monitoring
devices
s
n
o
i
tsn reca iltca</p>
      <p>Process mining</p>
      <p>output
Machine learning</p>
      <p>Figure 1 illustrates an E-mental health system architecture where a FHIR
database is used to store the data captured from healthcare service providers as
well as patients personal healthcare devices and applications. A care ow
analysis tool is used to perform data analysis including process mining and machine
learning. The care ow analyzer prepares the event logs by querying the FHIR
database. Security and privacy are major concerns for healthcare systems.
Different types of users may be involved in the process mining related work. The
users must have proper authorization to access patients healthcare information.
It might be possible to give partial access to the healthcare information stored
in the FHIR database. A FHIR interceptor is incorporated in the system
architecture to handle users authorization to access FHIR resources. The interceptor
will intercept all the FHIR queries and consults with an identity and access
management module and returns data that the user is authorized to access.</p>
      <p>
        We have developed applications to provide digital interventions for some
clinical cases such as managing depression, monitoring bipolar patients status,
treatment for social anxiety disorder [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ]. Currently patients need to sign up
to become a part of a clinical study program and they use their BankID for
authentication which is a personal electronic ID used to identify and sign online.
BankID is a Public Key Infrastructure (PKI) solution o ered by Finance Norway.
The solution supports both authentication and signing. Our future plan is to
incorporate blockchain technology using hyperledger fabric [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ] where the patients
would be able to receive mental healthcare services anonymously. Public stigma
is a barrier to mental healthcare and many people either do not seek treatment
or dropout from mental health treatment. We look forward to a solution where
patients identity will be hidden but they will be able to get help from a support
group of professionals. The patient will own the data and they will be able to
decide if they want to share their records with their therapist. We will study the
applicability of blockchain technology in developing E-mental health solutions
by exploring the potential of using blockchain technology to incorporate security,
privacy and integrity of medical records.
3
      </p>
    </sec>
    <sec id="sec-3">
      <title>Data analysis</title>
      <p>
        Typically, a process model describes the activities needed to be performed within
a given process by di erent actors such as physicians, nurses, and lab technicians.
Therefore, mining a process would in general extract a process model
representing the activities being performed in a healthcare system. The primary focus of
process mining in healthcare is to provide evidence-based process analysis
techniques for e ective process management [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]. It is used to discover trends and
patterns of process executions by analyzing the trace of activities (a.k.a event
logs) performed in a system. Due to the multidisciplinary nature of healthcare,
the event logs need to be harmonized before they can be processed. Getting the
right setup for data preparation is important to get the best understanding out
of the data as e ectively as possible [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ]. In a healthcare setting, the data
preparation task is complex due to the involvement of various healthcare systems and
variations of data formats. We propose to employ data warehouse techniques to
pre-process vast amount of information.
      </p>
      <p>
        Existing process mining tools or techniques [
        <xref ref-type="bibr" rid="ref1 ref14 ref15">1, 14, 15</xref>
        ] have limited support to
provide abstraction from di erent perspective, and healthcare analysts currently
need to perform a lot of manual investigation to nd out the pattern of patients
treatment ow. Given a large number of patients records, this is not an e cient
process as they need to change context from one patient group to another and,
need to look into the data for a speci c time range. To overcome this
limitation, we propose to develop a diagrammatic approach that will allow analyst to
specify process mining requirements diagrammatically such as the context and
abstraction level.
3.1
      </p>
      <sec id="sec-3-1">
        <title>Role of ontologies in process mining</title>
        <p>
          Ontologies are often used to standardize terminologies in healthcare. For
example, the ICD-10 (International Classi cation of Diseases) ontology is designed
to provide diagnostic codes for classifying diseases, including wide variety of
signs, symptoms, abnormal ndings, etc. The SNOMED CT [
          <xref ref-type="bibr" rid="ref4">4</xref>
          ] ontology
provides a comprehensive terminology for clinical health. It has been well accepted
Paediatrics
        </p>
        <p>Orthopedic
Dermatology
Care Plan</p>
        <p>Episode</p>
        <p>Of Care</p>
        <p>Healthcare
Observation</p>
        <p>Procedure</p>
        <p>Gynocology</p>
        <p>Psychiatry
Clinical
finding</p>
        <p>HL7 FHIR resources
EpisodeOfCare</p>
        <p>Observation</p>
        <p>Procedure
Clinical findings
regarding mental and
behavioral disorders</p>
        <p>Condition</p>
        <p>CarePlan
by healthcare professionals worldwide and its use has improved the quality of
medical health records by providing consistency in using medical terms.
Ontologies can be used to de ne suitable level of abstraction for selecting a particular
patient group and for visualizing care- ow from a high level of abstraction. We
intend to provide a customizable framework where domain ontologies such as
ontologies for care-plans, symptoms can be easily constructed and attached to
the data source.
3.2</p>
      </sec>
      <sec id="sec-3-2">
        <title>Dimensional modeling</title>
        <p>
          The concept of dimensional modeling originated from data warehousing and
business intelligence (DW/BI) [
          <xref ref-type="bibr" rid="ref9">9</xref>
          ]. Dimensional modeling has emerged as the leading
architecture for building integrated DW/BI systems. Dimensional models
package the data in a format that allows simplicity for displaying understandable
information to business users and also supports developing e cient data analytic
tools in terms of query performance. We propose to use dimensional modeling
for specifying process mining requirements. The dimensional models are used
for both ltering and selecting the level of abstraction for visualizing the process
mining output. For instance, an analyst may be interested to investigate the
admission ow of patients who have issues related with mental and behavioral
disorders. He needs to know which other departments the patients also visit. He
does not need to know the details about the clinics in the departments where
the patients visit. We assume that the department hierarchy of the hospital is
used for the `Admission' dimension. We illustrate the situation in Figure 2 to
visualize how the dimensional model and the hierarchical representation of data
can be utilized to specify such requirements. The purpose of this dimensional
model is to provide an easy to use visualization for its user to investigate care ow
from di erent context. We have used ontological hierarchies to provide
hierarchical representation of healthcare information along each dimensional model.
In this gure, `F00-F99' is the ICD-10 code for `mental and behavioral
disorder' diseases. Selecting `F00-F99' for ltering essentially means to lter based
on the sub-diseases under `F00-F99' which are depicted as small orange circles
in the gure. Performing this lter over the FHIR resources extracts the
`condition' FHIR resources where patients condition has been identi ed as one of
the sub-disease code of `F00-F99'. We use this ltered patients identi cations to
extract their admission resources. Patients admission resources contain
information about patients visit to di erent clinics. Since we need to display patients
admission to the departments, we use departments hierarchical information to
manipulate the results displaying department names instead of clinics name.
This example illustrates the department hierarchy of the Haukeland University
Hospital for the `Admission' dimension. We use this ltered patients' identi
cations to extract their admission resources. Patients admission resources contain
information about patients visit to di erent clinics.
4
        </p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>Conclusion and Future work</title>
      <p>
        The establishment of any large IT infrastructure for healthcare on a regional,
national or international level governs by political in uences. The Norwegian
Center for E-health Research recently published a report [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ] on reviewing the
focus on machine learning, natural language processing, data mining and process
mining methods: their usefulness, use cases, tools and relatedness to Norwegian
healthcare. The report emphasized on doing more research in machine learning,
data and process mining and natural language processing. Our e ort on
developing a software infrastructure for E-mental health is aligned with the focus and
interest published by the report. Interoperability and healthcare analytics are
two major topics in healthcare related research. In this paper, we proposed an IT
infrastructure for E-mental health to achieve interoperability and data analysis
with cutting-edge technologies.
      </p>
    </sec>
    <sec id="sec-5">
      <title>Acknowledgement</title>
      <p>This work is partially supported by The Research Council of Norway as a part of
the INTROducing Mental health through Adaptive Technology (INTROMAT)
project under grant agreement 259293.</p>
    </sec>
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