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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Defining Quality of Experience in e-Learning: a Literature Review</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Athanasia Kylafi</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Nikolaos Misirlis</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Yiannis Nikolaidis</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>HAN University of Applied Sciences</institution>
          ,
          <addr-line>R31, 6824DG, Arnhem</addr-line>
          ,
          <country country="NL">The Netherlands</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>University of Macedonia</institution>
          ,
          <addr-line>156 Egnatia Street, 546 36, Thessaloniki</addr-line>
          ,
          <country country="GR">Greece</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2023</year>
      </pub-date>
      <fpage>28</fpage>
      <lpage>29</lpage>
      <abstract>
        <p>Our research aims to investigate the “quality of experience” in education and particularly in the context of e-learning. Firstly, we study separately the concepts of “quality” and “experience”, as well as the underlying meaning of these terms. Secondly, through a scoping review among papers of the last decade, we study how “quality of experience”, as a whole, is defined in e-learning. Our purpose is to set a solid basis for the clarification of “quality of experience” in e-learning, considering that it is important to have a clear view of concepts before proceeding with a research related to them. As a result of our review, we reach useful answers to questions such as “What is quality of experience in e-learning?”, “Is quality of experience different from user experience?” gaining deeper understanding of the examined concepts.</p>
      </abstract>
      <kwd-group>
        <kwd>1 quality</kwd>
        <kwd>quality of experience</kwd>
        <kwd>e-learning</kwd>
        <kwd>literature review</kwd>
        <kwd>scoping review</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>There is no doubt that e-learning, which is defined as “the learning supported by digital electronic
tools and media” [1], especially after the Covid pandemic, has become a necessity in the educational
sector globally, either it concerns school education, higher education or vocational education and
training. Thus, it is reasonable that there is an increasing interest in optimizing e-learning procedures
and tools in order to offer e-learning services of high quality. This interest derives not only from the
educational organizations that wish to pioneer and to be competitive, but also from researchers and
academics that constantly look for new ways to evaluate and improve e-learning environments.
Therefore, it comes that the concept of quality is crucial when it relates to education and especially
elearning, mainly because the latter is delivered via digital technologies, which in fact mediate the
educational process and transform the connections among the participants (teachers and students).</p>
      <p>
        In general, it is difficult to define quality in a unique way, because it is a subjective, relational and
multidimensional concept. Actually, there is a long debate about its definition. Ehlers [
        <xref ref-type="bibr" rid="ref1">2</xref>
        ]
distinguishes three components of this debate on quality, as shown in fig. 1. According to him, it is
not easy to define quality because of a) different interpretations of quality, b) different players with
different perspectives of quality, c) different forms of quality.
      </p>
      <p>
        However, generally speaking and according to Juran, quality can be defined as “the degree to
which a product / service meets or exceeds expectations / requirements of customers” and “fitness for
use”. According to Crosby, quality means “conformance to requirements”. According to ISO 8402
[
        <xref ref-type="bibr" rid="ref2">3</xref>
        ], quality is “the characteristics of a product or service that bear on its ability to satisfy stated or
implied needs”. Finally, another definition of quality is given in the Qualinet White Paper [
        <xref ref-type="bibr" rid="ref3">4</xref>
        ]:
“Quality is the outcome of an individual‟s comparison and judgment process. It includes perception,
reflection about the perception, and the description of the outcome. In contrast to definitions which
see quality as a „set of inherent characteristics‟, quality is considered in terms of the evaluated
excellence or goodness, of the degree of need fulfillment, and in terms of a „quality event‟”.
      </p>
      <p>As can be seen from the above, quality may refer either to services or to products and according to
this basic distinction it could be categorized into further types, e.g. “quality of conventional services”
and “quality of e-services”. Following a conceptual path from quality to the central subject of our
study, namely the quality of experience in e-learning, we present in what follows the state of the art
knowledge regarding the related concepts.</p>
      <p>
        Specifically about services, Ehlers [
        <xref ref-type="bibr" rid="ref1">2</xref>
        ] mentions Donabedian‟s statement of the relational nature of
quality: “quality is the degree of conformance between a performed service and the goals set for this
service”. Similarly, according to Parasuraman et al. [
        <xref ref-type="bibr" rid="ref4">5</xref>
        ], service quality can be defined as “perceptions
(that) result from a comparison of consumer expectations with actual service performance”. From this
point of view, service quality is measured by calculating the difference between expectations and
perceptions.
      </p>
      <p>
        With the advent of the internet to most aspects of human activity in modern societies, more and
more conventional services are extended to electronic, namely e-services. The latter are web-based
services, which are delivered through electronic media (e.g. computers, smartphones, tablets). Thus,
the characteristics of services and e-services vary to a great extent and, therefore, the quality
dimensions of services and e-services vary too [
        <xref ref-type="bibr" rid="ref5">6</xref>
        ]. One well-known definition of the quality of
eservices is the following: “E-service quality is defined as the extent to which a website facilitates
efficient and effective shopping, purchasing, and delivery” [
        <xref ref-type="bibr" rid="ref6">7</xref>
        ]. Of course, this definition does not
actually reflect the wide range of e-services that exist nowadays (e.g. e-learning, e-banking,
egovernment, etc.), but we evaluate positively the fact that it focuses on two important elements,
efficiency and effectiveness. According to the above definition, e-service quality is the degree of
efficiency and effectiveness of services delivered to users on the internet.
      </p>
      <p>
        Taking one step further, e-learning - as an educational service offered through digital resources on
the internet - is undeniably a form of e-service. Quality of e-learning is defined as “the philosophy of
achieving excellence in all aspects of education through e-learning technologies” [
        <xref ref-type="bibr" rid="ref7">8</xref>
        ].
      </p>
      <p>Exploiting the previously described definition of quality, we consider the quality of e-learning as
the degree to which an e-learning course meets or exceeds the expectations / requirements of learners,
providing them with educational experiences. Quality of e-learning may refer to the educational
technology, the educational content, the teaching-learning process, the student assessment, the
administrative support etc.</p>
      <p>
        Through e-learning environments, the participants acquire various educational experiences. An
experience is defined as “an individual‟s stream of perception and interpretation of one or multiple
events” [
        <xref ref-type="bibr" rid="ref3">4</xref>
        ]. Experiences in e-learning may refer to teachers, to students or both. Moreover,
experiences are connected to the quality that characterizes every e-learning environment (and every
educational environment generally), meaning that there may be good or bad experiences. Ιn other
words, there may be high or low quality of experience. The latter is defined as follows:
“Quality of Experience (QoE) is the degree of delight or annoyance of the user of an application or
service. It results from the fulfillment of his or her expectations with respect to the utility and/or
enjoyment of the application or service in the light of the user‟s personality and current state” [
        <xref ref-type="bibr" rid="ref3">4</xref>
        ].
      </p>
      <p>
        Discussing quality of experience in the context of e-learning, quality is an important factor for the
future of e-learning [
        <xref ref-type="bibr" rid="ref1">2</xref>
        ]. On the other hand, experience of the learners is a crucial factor for the overall
success of an e-learning course, because it directly affects their learning outcome(s). Through their
experience, the learners fulfill their expectations and gain satisfaction and knowledge. So, from the
learners‟ perspective, the concept of quality is perceived as their experience, based on their
expectations and satisfaction.
      </p>
      <p>The purpose of this paper is to explore the literature of the last decade, in order to determine and
clarify the concept of QoE in e-learning. We also aim to gain deeper understanding of the concept, by
searching for answers to research questions such as:
Research Question 1: What is QoE in e-learning?
and
Research Question 2: Is QoE different from user experience?</p>
      <p>To serve our purpose we conduct a scoping literature review, as this type of review is the most
appropriate to gather knowledge, clarify concepts and identify gaps on a particular topic. The findings
of this review hopefully provide a clear understanding of QoE to researchers and other stakeholders in
the field of e-learning (e.g. academics, practitioners, organizations). They also indicate the recent
trends of research on QoE in e-learning.</p>
      <p>The paper is organized as follows. In Section 2 we present the methodology of the scoping
literature review. In Section 3 we go on with the results of our review and in Section 4 we discuss the
findings. In Section 5 we provide our conclusions.</p>
    </sec>
    <sec id="sec-2">
      <title>2. Literature review methodology</title>
      <p>
        A literature review is a form of research for knowledge synthesis. There are many literature review
types, such as narrative review, systematic review, scoping review, mapping review etc. [
        <xref ref-type="bibr" rid="ref8 ref9">9, 10</xref>
        ]. For
the purpose of this paper, we consider the scoping review as the most appropriate. Scoping reviews
belong to the category of rapid reviews [
        <xref ref-type="bibr" rid="ref8">9</xref>
        ]. A scoping review is suitable for exploring, identifying,
mapping, reporting or discussing characteristics or concepts across a breadth of evidence sources [
        <xref ref-type="bibr" rid="ref10">11</xref>
        ].
It is used for clarifying concepts, identifying knowledge gaps and providing an overview of the
existing knowledge. The present study is guided by the PRISMA 2020 statement [
        <xref ref-type="bibr" rid="ref11">12</xref>
        ] and the
PRISMA extension for Scoping Reviews Checklist [
        <xref ref-type="bibr" rid="ref12 ref9">10, 13</xref>
        ], and was conducted in 5 stages [
        <xref ref-type="bibr" rid="ref8">9</xref>
        ]:
Stage 1: identifying the research question(s)
Stage 2: identifying relevant publications / studies
Stage 3: selection of publications / studies
Stage 4: charting the data
Stage 5: collating, summarizing and reporting the results
      </p>
      <p>The purpose and the research questions of our research (Stage 1) are mentioned at the end of
Section 1. Next, (as per Stage 2) we selected the database of Scopus and determined the search
criteria to trace the relevant literature: boolean search of the terms “quality of experience” AND
“elearning” in title-abstract-keywords, filtered with the year range “2014-2023”. We continued with the
inclusion or exclusion of the publications that had arisen (Stage 3). Publications that either were
irrelevant to our research or did not provide any definition of QoE were excluded. We then studied the
selected publications and extracted the useful information (Stage 4). Finally we summarized the
findings (Stage 5).</p>
      <p>Our search in Scopus initially brought 122 records as a result. After the removal of 4 records due
to duplication, retraction and other reasons, 118 records remained. At the first screening 67 records
were excluded as irrelevant. We proceeded to the second screening for retrieval of the reports related
to our purpose, where 45 reports were retrieved. We assessed thoroughly all 45 retrieved reports for
eligibility. 29 of them were excluded with reasons (no definitions detected). We finally included 16
studies in the review.</p>
      <p>In Table 1 we provide the results of our review in chronological order. For each reviewed study we
present the definitions/meanings of QoE mentioned in it. In addition, we present the research topics in
the field of e-learning that the study relates to. The related research topics are of great interest because
they offer more detail on the meaning of QoE. Moreover, we note the type of publication.</p>
    </sec>
    <sec id="sec-3">
      <title>3. Results</title>
      <p>Idrizi, Filiposka,
Trajkovik</p>
    </sec>
    <sec id="sec-4">
      <title>4. Discussion of the findings</title>
    </sec>
    <sec id="sec-5">
      <title>4.1. Basic characteristics of the studies</title>
      <p>10 articles out of 16 (62.5%) are published between 2020 and 2023 and the rest (37.5%) from 2015
to 2019. The majority of them (75%) are conference papers, which implies that the particular research
area is still unexplored, thus very promising.</p>
      <p>
        The research topics of selected studies vary depending on the e-learning area, the applied
technologies and the type of educational content. Topics that refer to the field or a sub-field of
elearning are the following:
 video-based online learning [
        <xref ref-type="bibr" rid="ref13">14</xref>
        ]
 online learning [
        <xref ref-type="bibr" rid="ref16">17, 23, 24</xref>
        ]
 digital training [
        <xref ref-type="bibr" rid="ref17">18</xref>
        ]
 language learning [20, 22]
 virtual training [25]
 mobile learning [26, 27, 29]
 mooc [28]
Topics that refer to the technology or the content of e-learning are:
 video streaming [
        <xref ref-type="bibr" rid="ref13 ref16">14, 17, 19, 21</xref>
        ]
 machine learning [
        <xref ref-type="bibr" rid="ref13">14</xref>
        ]
 web service for course selection [
        <xref ref-type="bibr" rid="ref14">15</xref>
        ]
 virtual reality [
        <xref ref-type="bibr" rid="ref15 ref17">16, 18, 21, 22, 25</xref>
        ]
 gamification [
        <xref ref-type="bibr" rid="ref15">16, 22</xref>
        ]
 internet-based resources [20]
 videoconferencing [23]
 multimedia [23, 26, 27, 29]
 learning styles [24]
 cloud computing [26, 29]
      </p>
      <p>Finally, another characteristic is that all 16 studies approach e-learning from the learners‟
perspective.</p>
    </sec>
    <sec id="sec-6">
      <title>4.2. Ηow is QoE defined in e-learning?</title>
    </sec>
    <sec id="sec-7">
      <title>4.2.1. What is QoE in e-learning?</title>
      <p>
        According to the definitions presented in Table 1, QoE is considered as:
 a measure of satisfaction [
        <xref ref-type="bibr" rid="ref14 ref16">15, 17, 24</xref>
        ]
 a measure of experience [
        <xref ref-type="bibr" rid="ref15 ref17">16, 18, 21, 29</xref>
        ]
 the acceptability of an application or service [19, 20, 23, 25, 26]
 the delight or annoyance from an application or service [20, 25, 29]
 a subjective perception by the user [
        <xref ref-type="bibr" rid="ref13 ref14 ref15">14, 15, 16, 20, 22, 26, 28</xref>
        ]
 a multidimensional concept [25, 26, 29]
 a factor of user's engagement [27]
      </p>
      <p>From the above conceptual variety, we confirm that QoE in e-learning is multidimensional and
subjective, thus it is defined depending on the dimensions of the research interest. However, very
often the definitions overlap and have many elements in common. We infer that experience and
satisfaction are related concepts, both user-centric and user-perceived, and their measurement
determines QoE. We also infer that most of the studies adopt mainly two definitions of QoE, either
directly or with some paraphrase, which are a) the definition by the ITU (i.e., “the overall
acceptability of an application or service, as perceived subjectively by an end-user”) and b) the
definition by the Qualinet White Paper (i.e., “the degree of delight or annoyance of the user of an
application or service”). At this point it is noteworthy to mention the statement of Karadimce and
Davcev [29] that “QoE is no longer an expression for user satisfaction of using a service, but it is a
degree of delight or annoyance, which is a more dynamic measure of personal experience”. This
indicates the subjective character of QoE.</p>
      <p>
        According to the above definitions, QoE is affected by factors such as:
 the type of device and the quality of the Internet connectivity [
        <xref ref-type="bibr" rid="ref13">14</xref>
        ],
 presence, flow and symptoms in VR [
        <xref ref-type="bibr" rid="ref15">16, 21</xref>
        ]
 quality variation, stalling, and initial delay in a streaming session [
        <xref ref-type="bibr" rid="ref16">17</xref>
        ]
 user expectations and context [19]
 user‟s personality, current state, and expectations for the utility and/or enjoyment of the
application service [20]
      </p>
      <p>Additionally, as there is no single definition of QoE, it is difficult to evaluate the particular
concept [26] or, at least, there is no single measure of it. The measures of QoE vary as dependable on
the various factors that are taken into account in every research.</p>
    </sec>
    <sec id="sec-8">
      <title>4.2.2. Is QoE different from user experience?</title>
      <p>
        The answer to this question is that QoE and user experience (UX) are very similar concepts, since
both of them refer to users‟ experience with digital technologies. However, they are not exactly the
same. We infer that UX is the experience perceived by the user, while QoE is a measure for UX [
        <xref ref-type="bibr" rid="ref15 ref17">16,
18, 21, 29</xref>
        ]. More specifically, Bieg et al. [
        <xref ref-type="bibr" rid="ref17">18</xref>
        ] mention an interesting description of QoE, “as one of
the six measures for experience, along with hedonic user experience, pragmatic user experience,
VRinduced symptoms, sense of presence, overall satisfaction”. From this statement we conclude that
QoE and UX are not the same.
      </p>
    </sec>
    <sec id="sec-9">
      <title>5. Conclusions</title>
      <p>Concluding our review, we find out that there is not a specific, widely accepted definition of QoE
in e-learning. The adopted definitions in the field of e-learning are also used in other fields, as QoE is
defined for all e-services. Moreover, most studies in this review approach e-learning from a technical
view, mainly through computer science, thus QoE is mainly related with technical aspects of the
elearning systems. QoE is a concept often used in a technical context [30]. We agree with Kist and
Brodie [30], that the learning experience differs significantly from the general consumer experience.
We also agree with Ehlers and Hilera [31], according to whom “quality in the field of e-learning is an
especially diverse field, because it brings together the field of education, technology, and economy in
order to contribute a) to societal development, b) to innovate formal, non formal, and informal
learning opportunities, and c) empower learners as citizens to take part in our emerging learning and
information societies”. We believe that QoE in e-learning is a concept that refers to learning
processes, through learning environments, where learning objectives exist and learning outcomes
happen. Learners are more than consumers of a service, they acquire knowledge and they develop
skills and attitudes in a long-term horizon, apart from their short-term experiences. So, QoE in
elearning needs to be defined more specifically and this is certainly a research gap which should be
studied in the near future.</p>
      <p>This review also reveals that the research focus concerns only the learners‟ perspective. This was
expected, as learners are the main end-users in e-learning and actually the user-perceived experience
refers to the learners‟ experience. However, this fact can be seen as a research gap, because teachers
are highly involved in e-learning too (except self-learning cases), and their experience may have a
significance for the overall QoE, e.g. in higher education. This review also shows that QoE is not easy
to evaluate and this can be considered as another research gap too.</p>
      <p>This review has some limitations regarding the generalization of the findings. Due to the fact that
it was conducted in only one database, Scopus, more research is needed, expanded in more databases
in order to come to general results. The time span is also a limitation of this review.</p>
    </sec>
    <sec id="sec-10">
      <title>6. References</title>
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