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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Crafting Privacy: Two Case Studies Integrating Cross- Disciplinary Perspectives on Privacy in Design</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Maaike Harbers</string-name>
          <email>m.harbers@hr.nl</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Mortaza S. Bargh</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Florian Cramer</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Sunil Choenni</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Jeannette Nijkamp</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Anne Nigten</string-name>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Ministry of Justice and Security</institution>
          ,
          <addr-line>The Hague</addr-line>
          ,
          <country country="NL">The Netherlands</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Rotterdam University of Applied Sciences</institution>
          ,
          <addr-line>Rotterdam</addr-line>
          ,
          <country country="NL">The Netherlands</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>The Patching Zone</institution>
          ,
          <addr-line>Rotterdam</addr-line>
          ,
          <country country="NL">The Netherlands</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>Privacy by design is a widely acknowledged necessity, yet its practice is still in its infancy. Many scholars have argued that privacy by design requires a cross-disciplinary approach in which privacy perspectives from different disciplines need to be integrated from the beginning of the design process. This paper investigates the potentials and shortcomings of a workshop format, used in the early stages of a (re)design process, to integrate viewpoints of multiple stakeholders from different disciplines. The workshop is used in two cases involving privacy issues, in the healthcare and in the insurance domain. The results show that different stakeholders, representing social, technological, ethical, legal, domain and user perspectives, identified different problems. Together, they thus provided a more complete view on the issues at stake, forming a better starting point to account for privacy in the design process. Based on the results, the paper suggests a number of research directions for combining diverse views from multiple stakeholders.</p>
      </abstract>
      <kwd-group>
        <kwd>Privacy by design</kwd>
        <kwd>cross-disciplinary</kwd>
        <kwd>information technology</kwd>
        <kwd>human computer interaction</kwd>
        <kwd>IT</kwd>
        <kwd>HCI</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>
        The ubiquitous presence of technology creates ever more urgency to account for
privacy issues [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ]. Considering and accounting for privacy during the design of
information systems is often referred to as ‘privacy by design’ [
        <xref ref-type="bibr" rid="ref1 ref10 ref12 ref16">1,10,12,16</xref>
        ]. Privacy by
design has become particularly prominent due to the European Union’s General Data
Protection Regulation (GDPR), that has gone into effect in May 2018, which requires
meeting the principles of privacy by design when processing personal data [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ].
      </p>
      <p>
        One of the best-known works on privacy by design is by Cavoukian [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ], introducing
seven design principles to enable individuals to gain personal control over their
information and to enable organizations to gain a sustainable competitive advantage.
Cavoukian’s principles are high-level guidelines that still need to be translated to actual
system designs and engineering practices [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]. Currently, there exist no well-established
Copyright © 2019 for this paper by its authors. Use permitted under Creative
Commons License Attribution 4.0 International (CC BY 4.0).
approaches for translating the high-level privacy by design principles to practice
[
        <xref ref-type="bibr" rid="ref19 ref23 ref8">8,19,23</xref>
        ].
      </p>
      <p>
        One of the major challenges in applying privacy by design is that it requires the
integration of perspectives from multiple stakeholders (user, designer, developer, etc.)
and disciplines (HCI, software engineering, law, etc.) [
        <xref ref-type="bibr" rid="ref15 ref4 ref5 ref8">4,5,8,15</xref>
        ]. In the area of
requirement engineering, a number of methods have been proposed that integrate multiple
perspectives to elicit privacy-related system requirements, e.g. by using multiple
information sources [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ], questionnaires and scenarios [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ], and workshops with multiple
stakeholders [
        <xref ref-type="bibr" rid="ref17 ref2 ref3 ref5">2,3,5,17</xref>
        ].
      </p>
      <p>Although the above works aim at taking into account multiple perspectives in
eliciting privacy requirements, they do not elaborate upon how well the applied methods
integrate these perspectives in practice. In this paper, we therefore investigate the
potentials and shortcomings of using a workshop with multiple stakeholders as a method
to surface privacy-related problems from multiple perspectives, by applying it to two
design cases.
2</p>
    </sec>
    <sec id="sec-2">
      <title>Case studies</title>
      <p>
        The workshop we use is suitable for the initial phase of a systematic privacy by design
approach, aiming to identify privacy issues and trade-offs from multiple perspectives
related to the (re-)design of an information system. A diverse participant group is key
to the approach, as the participants represent multiple perspectives on privacy. The
workshop centers around a timeline, which serves as a boundary object to bridge the
participants’ domains of expertise [
        <xref ref-type="bibr" rid="ref21 ref22">21,22</xref>
        ]. This timeline is used to capture the flow of
data in the system to be (re-)designed. The use of a timeline with data is inspired by
mappings as known from IT and HCI/UX, such as a customer journey map [
        <xref ref-type="bibr" rid="ref11 ref14">11,14</xref>
        ],
threat modelling [
        <xref ref-type="bibr" rid="ref18">18</xref>
        ], and a typical data lifecycle (e.g., as considered by various spheres
in [
        <xref ref-type="bibr" rid="ref20">20</xref>
        ]).
      </p>
      <p>To gain practical experience with the workshop format, we organized two sessions
with 6 stakeholders: a problem owner (domain expert), an end-user, and four privacy
experts with a social, ethical, technical and legal perspective, respectively. The
workshops were led by a moderator (a designer). The roles of moderator and privacy experts
were fulfilled by researchers at Rotterdam University of Applied Sciences (RUAS), and
those of problem owner and end-user by people outside of RUAS, associated to the
respective domains. In an iterative design fashion, the results of the first session were
used to inform the second.
2.1</p>
      <sec id="sec-2-1">
        <title>Case 1: The OT black box</title>
        <p>The first case deals with the design of recording surgeries in the Operation Theater (OT)
in a so-called OT Black Box. Data stored in this OT Black Box contain video and audio
recordings of the OT, featuring the patient and the OT team, typically consisting of
surgeons, anesthesiologists, nurse anesthetists and OT nurses. These recordings are
later used by the OT-team to analyze and evaluate their performance, and by a quality
and safety manager to detect potential safety issues and improve the OT procedure if
possible. After two days, the recordings are anonymized (patient and OT-team are no
longer identifiable) and used for medical training purposes. Recordings are then no
longer available for the patient who underwent the surgery.</p>
        <p>Before the workshop, the moderator and problem owner prepared a timeline
consisting of five steps (see Figure 1). For each step, a large (A0-sized) paper was put on the
wall, on which the other workshop participants could write and add sticky notes. Each
participant was provided with markers and sticky notes of a unique color, so that the
contributions on the poster could be traced back to the different perspectives.</p>
        <p>The four-hour workshop session consisted of five activities. First, the design case
was introduced by the problem owner, explaining what happens in each timeline step.
Second, data assets per timeline step were identified by the workshop participants (first
individually, then in a group discussion), and added to the posters. Third, privacy
violation risks per timeline step were identified (first individually, then in a group
discussion), and added to the posters. Fourth, opportunities and risks of the information
system as a whole were determined and trade-offs were identified (in a group discussion).
Fifth, the workshop participants agreed on a set of design constraints, based on the
identified trade-offs (in a group discussion).</p>
        <p>Figure 1 shows some of the ‘data’ and ‘privacy risks’ that were identified per
timeline step. The overview is not exhaustive but intends to provide a gist of the
contributions from different participants. The results show that they bring in different
perspectives. For instance, the social privacy expert mentions that the patient’s dignity may be
at stake, whereas the legal privacy expert points at the application of a privacy impact
assessment.</p>
        <p>Fig. 1. Data and privacy risks identified by workshop participants for case 1 (OT Black Box).</p>
        <p>After identifying privacy risks, participants agreed that the most important trade-off
was improved healthcare versus deteriorated privacy, i.e., recordings by the OT Black
Box can enhance the quality of healthcare, but they introduce privacy violation risks
for both the patient and the OT team. There was little time left to perform the last
activity, identifying design constraints. Participants stressed that data should only be used
for the purpose they were collected for.
2.2</p>
      </sec>
      <sec id="sec-2-2">
        <title>Case 2: WhatsApp damage claims</title>
        <p>The second design case involves the use of the mobile application WhatsApp for
damage claims to an insurance company. The insurance company offers its customers the
possibility to send text and pictures of car damage (including pictures of the location)
via WhatsApp, when claiming the damage to the insurance company. These messages
and pictures are encrypted by WhatsApp.</p>
        <p>Although detailing the ‘data’ of all timeline steps in the first workshop brought
forward deeply engaged participants, it also led to discussions in which domain-specific
details were explored by non-experts. Moreover, it led to time shortage later on in the
session. We therefore asked the problem owner in the second workshop to detail the
data in each timeline step beforehand (Figure 2, 3rd column). The other workshop
activities remained the same.</p>
        <p>Figure 2 shows the results of the second workshop session. Again, these results are
not exhaustive, yet indicative. Similar to case 1, privacy issues related to ownership,
faulty data and function creeps were identified. In the discussions, a lot of attention was
paid to the trustworthiness of the photos sent for a damage claim via WhatsApp, as they
could easily be manipulated or uploaded from the internet. Thanks to the new setup of
the workshop, it was possible to complete all workshop activities this time.</p>
        <p>Participants identified a trade-off between ease of use and privacy. Using WhatsApp
for reporting damage increases ease of use for customers but introduces privacy risks
due to relying on a 3rd party service provider. Other trade-offs identified were
knowledge versus privacy (collecting and storing information increases insurers’
knowledge, but introduces privacy risks), costs versus privacy (building an in-house
application protects customers’ privacy, but increases costs), ease of use versus security
(as the ease of using WhatsApp creates security risks due to relying on a 3rd party
service provider).</p>
        <p>The workshop participants identified the following design constraints and
recommendations: 1) insurance companies should develop their own application rather than
relying on 3rd parties such as WhatsApp, this should be done according to privacy by
design principles, 2) customers should always be able to choose whether they want to
make use of WhatsApp, 3) customers should be informed about their options and the
implications of their choices, 4) as least data as possible should be collected, data should
not be collected if they will not be used, 5) customers should be able to access their
personal data stored by the insurance company, and 6) authorization of data access
should be implemented carefully in the insurance company in order to avoid function
creeps.
3</p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>Discussion and conclusion</title>
      <p>In both design sessions, stakeholders from different disciplines identified different
(privacy) problems and high-level requirements. For instance, the technical expert
focused on issues related to the processing of data, such as data leaks and
de-anonymization of data, whereas the social expert brought up the issue of human dignity and the
legal expert identified issues related to authorization of access. The number of
identified issues of all stakeholders was larger than any of the individual stakeholders’
contributions. Having multiple perspectives represented thus provided a richer view on the
design case at hand. Besides helping the privacy by design of IT systems, the workshops
were increasing awareness about privacy and its complexity among the participants,
i.e., they learned from each other and gained more insight in the complexity of privacy
by design.</p>
      <p>A number of issues should be considered when combining perspectives of multiple
stakeholders in a workshop in general, and in this workshop in particular. First, in a
multiple stakeholder workshop, there is a risk that some perspectives are more
dominant in the discussion than others. This could be countered by stricter time management
by the moderator, making sure that all participants receive an equal amount of speaking
time. Second, different perspectives, objectives and/or identified risks may not be of
equal importance. In future work, guiding principles for weighing different perspectives
should be developed. Third, the boundary object of a multi-stakeholder workshop, in
our case the timeline, steers the discussion in the workshop. In future research,
developing guidelines for preparing the timeline could help avoiding too directive
descriptions. Fourth, in our workshops, a number of well-known tradeoffs did not surface (e.g.,
data-subject/user control versus central/system control, prevention versus mitigation,
and technical versus procedural). This could be explained by a lack of expertise of the
participants. Yet, the likelihood of overseeing important trade-offs can be lowered by
providing more structure for discussing design trade-offs and providing design
recommendations, for example by systematically holding design tradeoffs along
various dimensions (e.g., data usage vs data privacy, data-subject control vs central control,
prevention vs mitigation, and technical vs procedural).</p>
      <p>
        In future work, we will take up the issues mentioned in this discussion and work on
the subsequent steps of a privacy by (re)design approach. We foresee the need of
developing a method that systematically translates the current workshop outcomes (i.e.,
design recommendations and constraints) into software requirements, e.g. by using
bridging concepts such as value stories [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ], turning privacy by design into privacy
engineering. For giving more structure to the design thinking process, we foresee
organizing the design discussions along three directions of security related aspects,
usersbeing-in-control related aspects and data-minimalization related aspects. The outcome
of these sessions should deliver a number of promising design options, which can be
prototyped and improved in a number of iterations.
      </p>
    </sec>
    <sec id="sec-4">
      <title>Acknowledgements</title>
      <p>The authors thank all the workshop participants for sharing their expertise and for their
valuable contributions.</p>
    </sec>
  </body>
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