MIND-VR: Design and Evaluation Protocol of a Virtual Reality Psychoeducational Experience on Stress and Anxiety for the Psychological Support of Healthcare Workers Involved in the COVID-19 Pandemic

To ensure the continuity of healthcare and to counter the spread of the COVID-19 pandemic, doctors and nursing staff at hospitals must face an insidious, invisible danger that is stretching the healthcare system far past its capacity. Excessive workload, inadequate protection from contamination, the need to manage patients experiencing extreme suffering and being kept apart from their families put medical personnel at high risk to experience stress and anxiety. Numerous scientific studies have shown that, among various therapeutic programs, virtual reality represents a highly specialized and effective tool for the prevention and treatment of stress and anxiety. However, the solutions developed using this technology for the management of stress and anxiety induced by the COVID-19 pandemic are still very limited, and none of these have been developed specifically for use with healthcare professionals. Therefore, this paper will detail the design and evaluation protocol of MIND-VR, a virtual reality-based psychoeducational experience on stress and anxiety developed following a user-centered design approach. The virtual experience will be tested on a sample of Italian hospital healthcare personnel involved in the COVID-19 pandemic emergency. MIND-VR is available free of charge, both in Italian and English, on the project website (https://mind-vr.com/).


INTRODUCTION
The novel coronavirus disease  pandemic is a global health emergency that is dramatically affecting the daily lives of millions of people worldwide (Johns Hopkins Coronavirus Resource Center, 2020), with serious consequences not only on a socioeconomic level but also on individuals' mental health (Cai et al., 2020a;Ma et al., 2020;Rogers et al., 2020;Vindegaard and Eriksen Benros, 2020;Zhao et al., 2020;Zheng, 2020). The adverse psychological consequences concern all those people forced into isolation and/or quarantine (Brooks et al., 2020), but especially healthcare workers involved directly in handling COVID-19 patients Kang et al., 2020;Liu et al., 2020).
Excessive workload, inadequate protection from contamination, and the need to manage patients experiencing extreme suffering and being kept apart from their families put medical personnel at high risk of experiencing stress (Bohlken et al., 2020;Greenberg et al., 2020;Qiu et al., 2020;Spoorthy, 2020), and anxiety Liu et al., 2020;Zhu et al., 2020). Stress classically is defined as "the bodily processes that result from circumstances that place physical or psychologic demands on an individual", and it is usually a short-lived response (Selye, 1973). Anxiety, instead, according to the American Psychiatric Association (APA), refers to "an emotion characterized by feelings of tension, worried thoughts and physical changes like increased blood pressure", and it generally is a long-term condition (Kazdin, 2000).
Excessive stress is a critical factor that could compromise healthcare workers' performance, (Dellve et al., 2011;Gandi et al., 2011), particularly during an emergency (Müller et al., 2009). Besides, high levels of stress and anxiety may have long-term physical and psychological consequences (Conway et al., 2008;Vinstrup et al., 2020). Therefore, urgent actions are needed to protect the mental health of those on the front line who deal with the management of the COVID-19 pandemic health emergency daily (Carmassi et al., 2020;Chirico et al., 2020;Krystal and McNeil, 2020). As underlined by a recent review (Weerasekara and Smedberg, 2019) and by the Italian Workers Compensation Authority and the Italian National Institute of Health, psychological support services should be based on enhancing the coping strategies for managing stress and anxiety of healthcare workers (Chirico et al., 2020;Italian National Institute of Health, 2020). However, little attention has been paid so far to the practical implementation of psychological interventions to help hospital staff Cheng et al., 2020;Weiner et al., 2020).
Within this context, new approaches to mental health integrating advanced technologies such as virtual reality should be considered (Pallavicini and Bouchard, 2019;Imperatori et al., 2020;. Nevertheless, the solutions developed using this technology for the management of stress and anxiety induced by the COVID-19 pandemic are still very limited , and none of these have been developed specifically for use with healthcare professionals. Therefore, this paper will detail the design and evaluation protocol of MIND-VR, a virtual reality-based psychoeducational experience on stress and anxiety developed following a user-centered design (UCD) approach. This virtual experience will be tested on a sample of Italian hospital healthcare personnel involved in the COVID-19 pandemic emergency.

Virtual Reality for the Management of Stress and Anxiety and Its Relevance During the COVID-19 Pandemic
Several studies have shown that virtual reality represents an advanced and effective tool for the prevention and treatment of stress and anxiety (Parsons and Rizzo, 2008;Maples-Keller et al., 2017;Oing and Prescott, 2018;Wechsler et al., 2019). The use of this immersive technology can help patients to learn useful resources to better manage anxiety (Gaggioli et al., 2014;Anderson et al., 2017;Lindner et al., 2019;Pizzoli et al., 2019), with therapeutic benefits similar to or even greater than those of traditional programs such as cognitive-behavioral therapy (CBT) interventions, (e.g. in vivo exposure and guided imagery) (Gerardi et al., 2008;Wechsler et al., 2019).
As underlined in a recent article, several characteristics make virtual reality particularly interesting in the prevention and treatment of stress and anxiety, especially during this historical moment linked to the COVID-19 pandemic (Imperatori et al., 2020). Among these characteristics, one of the most relevant is that virtual reality can help people acquire coping skills useful for managing stress and anxiety, including relaxation techniques (Stetz et al., 2011;Serrano et al., 2016;Anderson et al., 2017;Pizzoli et al., 2019), biofeedback Gradl et al., 2018), and mindfulness training (Kosunen et al., 2016;Navarro-Haro et al., 2017;Seabrook et al., 2020). Indeed, this technology has proven to be effective at inducing relaxation, eliciting positive emotions in users (Anderson et al., 2017;Lindner et al., 2019;Pizzoli et al., 2019;. In particular, the visual presentation of a relaxing virtual scenario can facilitate the practice of patients and the consequent mastery of relaxation techniques, making the experience more vivid and real than both photos/videos Gorini et al., 2011;Pallavicini et al., 2013) and using one's imagination and memory (Villani and Riva, 2008;Villani et al., 2009). For example, in April 2020, a virtual reality experience called "The Secret Garden" was developed to help people manage stress generated by the COVID-19 pandemic .
In addition to the ability of virtual reality to reduce levels of stress and anxiety through immersion in relaxing virtual environments, a particularly significant feature is linked to the usefulness of this technology within psychoeducational programs. This is particularly relevant since, as will be described in the following paragraph, mental health literacy-defined as knowledge and beliefs about mental disorders, which aid their recognition, management, or prevention (Jorm, 2000)-represents a key facilitator of formal help-seeking behavior (Rickwood et al., 2005;Gulliver et al., 2010).

The Potential of Virtual Reality for Psychoeducation on Stress and Anxiety
The term psychoeducation refers to interventions aimed at providing information on a psychological disorder in a clear and articulated way to make the patient more competent and aware of his problem, with a view to individual empowerment (Oflaz et al., 2008;Watkins et al., 2018). Psychoeducation represents a fundamental method of increasing adherence to therapy for mental disorders. It is considered a key part of cognitive-behavioral therapy (Richardson, 2017), which is, as reported by the American Psychological Association, a form of psychological treatment strongly evidence-based that emphasizes the strict connection between behavior, cognition, and emotions and on helping individuals learn to be autonomous. Psychoeducation can also be an intervention of its own, educating patients on their diseases and how to deal with them (Coulthard et al., 2013;Taylor-Rodgers and Batterham, 2014;Zhang and Ho, 2016).
Virtual reality (VR) represents a potentially very useful tool for psychoeducational programs, thanks especially to the greater involvement of users in the learning process compared to a standard lesson, such as learning from a textbook, slideshow, or lecture (Bailenson et al., 2008;De Freitas et al., 2010;Webster, 2016;Parong and Mayer, 2018). In particular, empirical studies suggest that this technology leads to better outcomes than slideshows or textbooks presented on desktop displays (Kozhevnikov and Gurlitt, 2013;Webster, 2016;Orman et al., 2017). Thanks to virtual reality individuals can experience a fully immersive sensory experience that may help them engage in deeper learning (Parong and Mayer, 2018).
To understand how the learning process takes place in virtual environments, it is essential to refer to the constructivist principles approach (Chittaro and Ranon, 2007;Dimitropoulos et al., 2007;Virvou and Katsionis, 2008;Huang et al., 2010). According to this paradigm, learning is situated: knowledge is based on active experience and is obtained through the construction of meaning in a certain learning environment. Learners take an active role in their learning, and the environment will affect the learner (Dewey, 1916). Immersive environments offer a variety of situated learning experiences different from what learners encounter in a traditional classroom or text-based learning. In virtual reality, learners can construct knowledge through interaction with objects and events in the artificial world (Chittaro and Ranon, 2007;Huang et al., 2010;Shin, 2017;Gomes et al., 2020). This technology creates a strong sense of presence, which in turn motivates and thereby causes the learner to cognitively process the learning material more deeply. In other words, learners begin actively learning (Huang et al., 2010).
Despite the important role that virtual reality could play in providing information regarding mental suffering conditions, only a few previous studies to date have investigated the possibilities of virtual reality for psychoeducation (Rizzo et al., 2009Riva et al., 2012;Tielman et al., 2017;Migoya-Borja et al., 2020). For example, a virtual environment called "Learning Island" and developed in Second Life, was created to host an interactive course on stress management (Riva et al., 2012). Also, a virtual reality-based psychoeducational tool for individuals suffering from depression called "VRight" has been shown to increase depressive symptoms awareness (Migoya-Borja et al., 2020). Within this context, MIND-VR's main goal is to develop an immersive experience offering psychoeducation on stress and anxiety. This virtual experience, as described below, was built following a UCD approach and will be tested on a sample of Italian hospital healthcare personnel involved in the COVID-19 pandemic emergency.

DEVELOPMENT AND EVALUATION PROTOCOL OF THE MIND-VR PSYCHOEDUCATIONAL VIRTUAL EXPERIENCE
Starting in July 2020, a team from the University of Milano-Bicocca, in collaboration with the authors of this paper and an Italian start-up specializing in the development of immersive solutions (AnotheReality), partnered to develop MIND-VR. Development funds (approximately $5,000) were raised thanks to a fundraising campaign that took place between April and June 2020 and was promoted by the University of Milano-Bicocca in collaboration with the platform Produzioni dal Basso.
MIND-VR is intended to be released immediately, to be easyto-use, enjoyable, and educational. Thus, principles and practices of UCD were followed in its design and development. According to the International Organization for Standardization (ISO), UCD, often used synonymously with "human-centered design," is defined as "an approach to systems design and development that aims to make interactive systems more usable by focusing on the use of the system and applying human factors/ergonomics and usability knowledge and techniques" (Woodson et al., 1992). UCD can be considered a multistage problem-solving approach that puts the product endusers, both expert and naïve, at the center of its design and development (Fischer and Coutellier, 2007;Barbieri et al., 2018).
This approach is used successfully in many application fields such as mobile and web application development (Taylor et al., 2011;De Paula et al., 2014;Lopes et al., 2018;Llema and Vilela-Malabanan, 2019), and healthcare technology (DeSmet et al., 2016;Schnall et al., 2016;Verschueren et al., 2019;Farao et al., 2020;Vandekerckhove et al., 2020). For example, a UCD process has been adopted to develop a digital platform offering psychological support to patients suffering from paranoia (Hardy et al., 2018). It has also been used to create video games to alleviate anxiety and depression symptoms (Dekker and Williams, 2017), and to promote physical exercise in older adults (Brox et al., 2017).
Regarding virtual reality, it has been demonstrated that, by optimizing the virtual environment's architecture, the use of UCD in the development of virtual experiences offers a more efficient, satisfying, user-friendly experience Jerald, 2015;Barbieri et al., 2018;Gladden, 2018). It has been employed to design and evaluate virtual experiences in museums (Barbieri et al., 2018), tourism (Poux et al., 2020), automotive industries (de Clerk et al., 2019), and military , and medical fields (Vailland et al., 2019). Furthermore, it has been used to develop virtual reality content for mental health (Fidopiastis et al., 2010;Koenig et al., 2012;Boger et al., 2018;Eisapour et al., 2018;Flobak et al., 2019;Pizzoli et al., 2019), particularly virtual environments for cognitive assessment and rehabilitation (Fidopiastis et al., 2010;Koenig et al., 2012), and to promote physical activity among people with mild cognitive impairment (MCI) Eisapour et al., 2018). The UCD approach has recently been proposed for prototyping virtual reality scenarios for exposure therapy in patients with fear of public speaking (Flobak et al., 2019), and for promoting relaxation (Pizzoli et al., 2019). Regarding virtual experiences of psychoeducation, to the best of our knowledge, only one previous work conducted a requirements analysis involving end-users to develop an immersive game for older adults with chronic back pain (Stamm et al., 2020). Therefore, MIND-VR represents one of the first few published attempts to adopt the UCD approach for the development of a virtual reality-based psychoeducational experience. Specifically, in the development of this virtual experience, the recommendations ISO 13407 (ISO/IEC, 1999) for a UCD project were adopted, and the main design phases were followed according to this approach, which will be described in detail in the following paragraphs. Psychologists with high expertise in creating virtual content for managing stress and anxiety follow developed the requirements, selected the architectural paradigm for the design of the virtual reality experience, and created content and evaluation protocol of MIND-VR in collaboration with psychotherapists who have assisted health professionals following the situation triggered by the COVID-19 pandemic and co-authored this paper.

Requirement Specifications
According to the ISO 9241-210:2010 (Woodson et al., 1992), before the design phase in a UCD approach, it is fundamental to take into account the gathering of requirements and specifications to better define the context of use and the needs of the end-users (Brox et al., 2017;Barbieri et al., 2018). For MIND-VR to be efficiently designed, end-users' needs and expertise were collected via semi-structured interviews conducted virtually in April 2020 with two psychotherapists who also co-authored this paper. The purpose was to find out the expectations, desires, preferences, and barriers to adopt a virtual reality experience for the management of stress and anxiety for healthcare workers. The interviews included the following main content categories: experience with treating stress and anxiety of medical staff during the COVID-19 pandemic; virtual reality knowledge and expertise; acceptance and experience with virtual reality system for the management of stress and anxiety for healthcare workers. The interviews lasted about 40 min. Subsequently, they were transcribed and analyzed to identify the main categories. A summarizing content analysis by Marying (Mayring, 2015) was applied for the data analysis. The transcripts were coded manually and were carried out by two scientists, using the four-eyes-principle to ensure reliable coding.
Based on the funds available for development and taking into account the interviews with the psychotherapists, MIND-VR had to satisfy four fundamental requirements: • Low cost: the funds for the development of this virtual experience were very limited (about 5,000 euros). Consequently, the best virtual content development solution-in terms of interaction mode, home construction, user data recording, etc.-had to be functionally relevant, cost-effective, and technically possible. • Easy to use: since the target of MIND-VR is represented by users who are not necessarily experts or with previous experience of virtual reality systems, (i.e. doctors and nurses), usability-namely, "the extent to which a product can be used, by specified users, to achieve specified goals with effectiveness, efficiency, and satisfaction in a specified context of use" (Malone, 1980(Malone, , 1982Nielsen, 1994)-was considered a key quality of the virtual experience. To ensure high usability of the content, various evaluation phases with the involvement of end-users were planned during development (see also Evaluation). • Pleasant and informative experience: in the development of MIND-VR, in addition to a strong focus on a simple and intuitive mode of interaction, the computer-generated graphics, and the related visual experience have been rendered with high quality to make the experience engaging and captivating. The conceptual framework defined as "emotional design" has been followed in the design of the virtual content (Norman, 2007). This framework highlights that an effective design is composed not only of a modality of interaction perceived as simple and intuitive, but also of the involvement of users' affective/visceral level through the use of physical features such as sight, touch, and sound. This theoretical approach has been adopted largely in the context of developing interactive content like video games (Baharom et al., 2014), and many other technological products (Desmet and Hekkert, 2007;Triberti et al., 2017). Particular attention was paid to the choice of colors and the selection of the fonts of all text present in the experience. Besides, MIND-VR was developed with extreme consideration of the sound aspect of the experience and its quality. For this purpose, the psychoeducational content includes audio recorded by professional actors and high-quality ambient sounds.
• Easily accessible: MIND-VR had to run on some currently more widespread, user-friendly, and low-cost headmounted display (HMD): Oculus Quest and Oculus Quest 2 (see also Implementation: MIND-VR hardware and software). Furthermore, since November 2020 the virtual experience can be downloaded for free, both in Italian and English, on the project website (https://mindvr.com/free-download/).

Selection of the Architectural Paradigm for the Design of the Virtual Reality Experience
This part of the design process started with an in-depth analysis of the literature on psychoeducation in programs for stress and anxiety (Romano, 1992;Houghton and Saxon, 2007;Donker et al., 2009;van Daele et al., 2012), and with the collection of information about products (commercial and non-commercial) in virtual reality built for educational purposes. Also, two psychotherapists (who are among the authors of this paper) were interviewed to explore: psychoeducation on stress and anxiety for healthcare workers; the essential element to be included in a virtual experience to offer basic education on stress and anxiety. The interviews lasted about 40 min and afterward were transcribed and analyzed. Then, a summarizing content analysis (Mayring, 2015) was applied. Based on the information and the scientific literature collected (Romano, 1992;Houghton and Saxon, 2007;Donker et al., 2009;van Daele et al., 2012), the architecture and the content of the experience were written. At the beginning of MIND-VR, the user is in a home, where three different icons are presented: "Tutorial," "Project information," and "A brief guide on stress and anxiety". The tutorial was inserted to offer the basic information necessary for the use of psychoeducational content (i.e., navigation mode through teleportation and the possibility of using it both standing and sitting on a swivel chair). In the "Project Information" section, on the other hand, there is information about the history and purpose of MIND-VR. Furthermore, since it has been shown that listening to some types of music can promote relaxation and increase positive emotions (Kuan et al., 2018;de Witte et al., 2020), a classical music piece has been included in the home of MIND-VR. In particular, the music is taken from Frederick Delius' Florida Suite: III "Near the Plantation," a piece that has proven effective in reducing stress and anxiety according to a previous study (Kuan et al., 2018).
As for the psychoeducational content, since the scientific literature suggests that naturalistic virtual environments cause a relaxing effect and an increase in positive emotions (Kahn et al., 2009;Anderson et al., 2017;Browning et al., 2020;Litleskare et al., 2020), a small tropical island was chosen as the setting. The prevailing colors are blue and green, as they are associated with positive affective states and neutral levels of emotional activation (Kurt and Osueke, 2014;Minguillon et al., 2017;Briki and Majed, 2019). The elements on the island, (i.e. palm trees, vegetation, a small lake over which there is a bridge, etc.) were inserted taking care that they are not too numerous to avoid elements that are excessively distracting for the user compared to the psychoeducational experience ( Figure 1).
The design of the experience is based on the theoretical framework of architectural paradigms for the UCD of virtual environments developed by Gladden (Gladden, 2018). By considering the unique possibilities for structuring and experiencing space within virtual environments and reinterpreting Norberg-Schulz's schemas in the context of virtual environment design (Norberg-Schulz, 1980), this framework formulated six fundamental architectural paradigms available to designers of virtual environments that could easily be incorporated as an additional step within the UCD process. In the design of the MIND-VR psychoeducational experience, the paradigm of the "Virtual Museum" was selected. This architectural paradigm can be used to create many types of virtual environments that are not literally meant to function as "museums," creating for users the atmosphere of a gallery whose visual and textual information are being displayed and appreciated. Inside these virtual museums, the person can follow a predetermined path or freely explore the environment (Gladden, 2018).
Based on this paradigm, the virtual island is divided into three areas, each focused on different aspects related to stress and anxiety and presented to the user through a map at the beginning of the content (Figure 2). In each area, the users have the opportunity to follow a predetermined path along which they will find information in text, audio, and image form on conditions of mental suffering. In particular, in some stages there is a wooden lectern above which a three-dimensional object is presented that represents the theme of the stage, (e.g. psychology symbol, DNA, etc.). By clicking on the object, the user is presented with information on stress and anxiety, both in text form, (i.e., written on the lectern) and audio ( Figure 3). The user can advance along the path and explore the island through teleportation, which has been evaluated as the simplest and most intuitive way of navigation (Bozgeyikli et al., 2016;Boletsis and Cedergren, 2019).
Concerning the specific content of the three paths, based on the information collected and the literature on psychoeducation in programs for stress and anxiety (Romano, 1992;Houghton and Saxon, 2007;Donker et al., 2009;van Daele et al., 2012), three fundamental issues emerged as the most relevant to be explored within the virtual experience. For each of these topics, the storyboard for the paths inside the island was created (see Table 1). The island is designed to be completed in three sessions, each trying a different path. Each of the routes takes about 15 min to be ended, for a total of about 45 min to finish the whole experience. The decision to limit the duration of the virtual experience to 15 min per session was made following the recommendations of the psychotherapists collected during the interviews. This also matches the health and safety warnings of the Oculus Quest (Oculus, 2020).

Implementation: MIND-VR Hardware and Software
Based on the elements that emerged in the previous phases, the psychologists who followed the MIND-VR design created a document for developers describing the basic requirements of the experience and its architecture. Besides, psychologists wrote the storyboards. They included a detailed description of all the visual elements (icons, objects, texts) and sound elements to be incorporated in the various parts of the content. Finally, the audio scripts created for each virtual island path were delivered to professional actors and recorded in mp3 format.
MIND-VR was developed over three months, between July and October 2020. This virtual experience was developed using Unity Engine, with scenes composed with 3D graphics created with 3DSMax, ZBrush, Substance Painter and thoroughly optimized to maintain high and stable framerate on the Oculus Quest. Logic and interactivity were programmed with C# using Microsoft Visual Studio 2019 and based on the SPACS framework.
The virtual experience has been designed to run on the headset Oculus Quest. It is also compatible with Oculus Quest 2. Oculus Quest can be used wirelessly as a standalone device with its FIGURE 1 | Screenshot of the virtual island developed for MIND-VR: a bridge on a small lake in the center of the island that users cross in the third path.
FIGURE 2 | Map of the three areas into which the virtual island is divided ("An introduction on stress and anxiety disorders", "Causes and symptoms" "Main Treatments").
Frontiers in Virtual Reality | www.frontiersin.org February 2021 | Volume 2 | Article 620225 6 integrated hardware. This HMD uses two diamond Pentile OLED displays, each with an individual resolution of 1,440 × 1,600 and a refresh rate of 72 Hz. It utilizes Oculus Touch controllers, which are tracked via an array of cameras embedded in the front of the headset. Like its predecessor, the Oculus Quest 2 (released in October 2020) is a standalone headset with an internal, Android-based operating system. It's lighter than the first-generation Quest and uses a single fast-switch LCD panel with a 1832 × 1920 per eye resolution, and it supports a 90 Hz refresh rate.

Evaluation
Following the UCD design process for optimizing the virtual experience, various phases of MIND-VR testing are envisaged. The studies have received ethical approval from the Ethics Committee of the University of Milano-Bicocca and the Foundation IRCCS Neurological Institute Carlo Besta. In the coming months, the experiments will be extended to include other Italian hospitals. All data collected will be stored anonymously in a web Central database Repository. Security and privacy issues will consider the respective situation and the participant's consent. Specifically, the study will follow the World Medical Association Declaration of Helsinki regarding ethical principles for medical research involving human subjects (World Medical Association, 2013). Concerning the COVID-19 infection prevention, specific safety and hygiene procedures will be adopted (see Table 2).

Pilot Study one
The first step will involve testing MIND-VR in a pilot study with a small portion of subjects recruited from the target population to verify the usability of and satisfaction with the mock-up (Alpha version) of the virtual content. The pilot study will be used to identify any problems during the interaction with users and to collect data that can be used in the development of the final version of the virtual experience (Beta version).

Path Title Content
First An introduction to stress and anxiety At the beginning of the path, stress and anxiety are defined, and their main characteristics are described. In the following stages, the relationships between the stress response and the autonomic nervous system are first explained, followed by the explanation of the meaning of "stress adaptation syndrome." toward the end of the path, the American Psychiatric Association (APA) definition of anxiety is given Kazdin (2000), and the various types of anxiety disorders are listed, as described by the DSM-5 American Psychiatric Association (2013) Second Causes and symptoms The first steps describe the physical, biological, and psychosocial factors that can contribute to generating a state of stress and the symptoms of stress (physical, behavioral, and emotional). The next section describes the main causes of anxiety (genetic and environmental factors) and lists the main symptoms of different anxiety disorders Third Main treatments The first steps describe the physical, biological, and psychosocial factors that can contribute to generating a state of stress and the symptoms of stress (physical, behavioral, and emotional). The next section describes the main causes of anxiety (genetic and environmental factors) and lists the main symptoms of different anxiety disorders Frontiers in Virtual Reality | www.frontiersin.org February 2021 | Volume 2 | Article 620225 7 • Study design and setting: This study will be using a small sample size and a mixed-methods design. Psychometric outcomes will serve as quantitative variables, while participant interviews will provide qualitative data. In the room where the experiments will be conducted, a second HMD will be available if the first one encounters technical problems to avoid problems with the experimental procedure and participants' disappointment. • Participants: Twenty healthcare workers will be recruited as a convenience sample. The participants' eligibility will be verified through an interview with a psychologist who will explain the purpose and procedures of the training and conduct an assessment to identify the participants who can enter the study. On this occasion, if the psychologist detects levels and symptoms of stress and/or anxiety of clinical interest, the participant will be sent to the Institutional Psychological Help Desk and will be excluded from the study. The study inclusion criteria will be: 1) maximum age of 65; 2) having worked on the front lines during the COVID-19 emergency; 3) absence of medical disorders (heart disease or blood pressure, neurological disorders, epilepsy); 4) absence of pharmacotherapy that could interfere with the measured data (psychoactive drugs, anti-hypertensive, anti-depressants); 5) no significant visual impairment (all with normal visual acuity or corrected to normal). Participants will be informed about the possibility to participate in the study with oral communication and a formal email from the institutional study referent. They should confirm their intent to participate in the study by answering that email and the referent will set an appointment for the screening interview, as described above. Eligible participants will be given written information about the procedure and asked to sign the consent form indicating their willingness to participate in the study. The participants will also be informed about the safety and hygiene procedures to prevent COVID-19 infection (see Table 2).
• Measures: Participants will complete a demographic questionnaire (age, years of education, profession, hospital, work department). They will also complete an ad hoc questionnaire assessing their use of technological solutions and virtual reality (see Table 3). To study the usability of MIND-VR, all participants will complete the following questionnaires after the virtual experience: System Usability Score (SUS) (Bangor et al., 2008); Slater-Usoh-Steed Presence Questionnaire (SUS-II) (Slater et al., 1994); Igroup Presence Questionnaire (IGP) (Schubert et al., 2001); Net Promoter Score (NPS) (Reichheld, 2003). These questionnaires have good internal consistency, with a Cronbach α coefficient ranging from 0.74 to 0.92 (Lewis and Sauro, 2009;Panahi-Shahri et al., 2009;Sauro and Lewis, 2011;Lotko, 2015;Schwind et al., 2019). Also, to measure changes in the affective states of users, the following scales will be administered: State-Trait Anxiety Inventory Y-1 (STAI Y-1) (Spielberger et al., 1983;Spielberger 2010); Visual Analogue Scale (VAS) (Aitken, 1969;Flint et al., 2000). The STAI-Y1 scale has high internal consistency, with a Cronbach α coefficient ranging from 0.86 to 0.95 (Spielberger, 2010;Julian, 2011;Rossi and Pourtois, 2012). Regarding the VAS, several studies have confirmed its reliability and validity (e.g. Luria, 1975;Gift, 1989;Abend et al., 2014). Finally, at the end of the experimental session, the participants will be interviewed for about 15 min. The questions will be based on the methodology used in a recent study (Migoya-Borja et al., 2020): Were there any features that you especially liked? Were there any features you did not like or found useless? Have you learned anything after using MIND-VR? Were there any features more useful than others? Would you like to have more sessions with MIND-VR? Do you have any questions or would like to add anything? • Procedure: At the beginning of the experimental session, participants will be asked to answer a questionnaire on their demographic, level of knowledge of technology and virtual

Safety and hygiene protocol
Instruct the participants on the safety and hygiene procedure • Inform the participants on the importance of the safety and hygiene procedure • The participant with cold-like symptoms will be asked to skip the experiment and notify the experimenter • During the experimental session, participants will be asked to follow specific precautions described below Follow the following precautions during the experimental session • To ensure the safety procedures for the prevention of COVID-19 infection, the experiments will be conducted in a clean and well-ventilated room inside the hospital • Before entering the room, both the experimenter and the participants will have to wash their hands with an alcohol-based disinfectant (at least 70%) • The participants will be asked to keep at least 1.5 m from the experimenter • All the questionnaires will be completed on a computer placed on a table about 3 m from the experimenter • The participants will take the headset placed on a table placed about 3 m away from the experimenter. They will be explained how to wear it and how to use it • After finishing the virtual experience, the participants will be asked to remove the headset and put it back on the table • The non-VR group will see the slideshow on the same computer on which they will answer the questionnaires Disinfect the computer keyboard and the headset • As soon as the experimental session is finished, the experimenter will use a detergent with at least 70% alcohol to decontaminate the computer keyboard and the headset.
• The cleanable, waterproof face part, keys areas of the headset (i.e., top and bottom, the headbands, buttons), and controllers will be disinfected and allowed to dry on a clean surface • At the end of the procedure, the experimenter will have to disinfect his/her hands again Frontiers in Virtual Reality | www.frontiersin.org February 2021 | Volume 2 | Article 620225 8 reality, and the STAI-Y1 and VAS. Subsequently, they will be able to use MIND-VR freely for about 15 min. The participants will then fill out questionnaires on the content's usability (SUS, SUS-II, IGP, NPS) and, again, the STAI-Y1 and VAS. Finally, a short interview of about 15 min will be conducted. The session will last approximately 40 min in total.
• Data analysis strategy: A descriptive statistical analysis of the usability questionnaires will be performed to evaluate the participants' acceptability of MIND-VR. Besides, the differences between the final and initial STAI-Y1 and VAS scores will be calculated. A Wilcoxon rank test will be conducted to determine whether the age, gender, or the level of knowledge of technology and virtual reality of the participants influences the usability questionnaires score or the change in the STAI-Y1 and VAS scores.

Pilot Study two
In the second step, MIND-VR (Beta version) will be tested on a small sample of target individuals to evaluate the learning experience of the basic information on stress and anxiety. Previous empirical studies suggest that virtual reality leads to better outcomes than slideshows or textbooks presented on desktop displays (Kozhevnikov and Gurlitt, 2013;Webster, 2016;Orman et al., 2017). However, since no study has yet specifically investigated learning psychoeducational content, the goal of Pilot Study two is to compare MIND-VR and a non-immersive modality (i.e. a slideshow on a computer screen) in the acquisition of information on stress and anxiety through MIND-VR and a non-immersive modality (i.e. a slideshow on a computer screen).
• Study design and setting: This pilot study will adopt withinsubject repeated measures (2 × 4) design. Participants will be randomly assigned to one of the two groups, the "VR Group" that will try MIND-VR, and the "Non-VR group" that will try a non-immersive (2D) slideshow. Data will be recorded on four-time points, including three follow-ups, at 1 week, 1 month, and 6 months to assess the long-term learning and its generalization. To avoid the disappointment of the participants who will try the slideshow, at the end of the experiment, individuals in the "Non-VR Group" will be offered the possibility to try MIND-VR for about 15 min. • Participants: Thirty healthcare workers will be recruited as a convenience sample. The recruitment methods and inclusion criteria will be the same as those adopted in Pilot Study 1. The participants in this experiment will be different from those in Pilot Study 1. • Measures: Participants will complete a questionnaire assessing their demographic characteristics and the use of technological solutions and virtual reality (see Pilot Study one for details). They will also fill in an ad hoc questionnaire measuring their background knowledge of stress and anxiety (see Table 4). We will use a self-reported background knowledge questionnaire rather than a pretest about the material presented in the study because we want to avoid a testing effect in which the pretest would serve as a form of instruction to prime learners to learn the answers before the actual lesson (Fiorella and Mayer, 2015). Furthermore, to measure subjective indices of the learning level of psychoeducational information, an ad hoc questionnaire on the learning level of psychoeducational contents will be administered at the end of the experimental session. The questions will be based on the methodology used in a recent study (Parong and Mayer, 2018) (see Table 5). Also, participants will be asked to complete a posttest containing 10 questions, eight factual questions in multiple-choice format, and two conceptual questions in short-answer format, assessing the learning outcome of participants based on their experience of the VR. An example of a factual question is, "Which is the first phase of the "General Adaptation Syndrome" (A) Resistance phase (B) Alarm phase (C) Exhaustion phase. An example of a conceptual question is, "What are the main symptoms of stress?". • Procedure: First, the experimenter will describe the study, and the participants will sign the informed consent form. Second, the participants will complete the demographic questionnaires, the ad hoc questionnaire on the use of technological solutions and virtual reality, and the background knowledge of stress and anxiety. Third, the psychoeducational material on stress and anxiety will be presented. In the VR condition, the participants will use MIND-VR for about 15 min and complete the island's first path (i.e. "Introduction on stress and anxiety"). In the Non-VR condition, each participant will try a 2D slideshow, which will present the same content as that included in the first path of MIND-VR. The slideshow will be presented on a desktop computer with a 20-inch color screen. Fourth, participants will complete a post-questionnaire about their experiences and a posttest on the material they viewed, with no time limit. Finally, participants will be thanked and dismissed. The session will last approximately 1 h. The same tests made at the end of the experimental session will be conducted also after 1 week, 1 month, and 6 months in the presence of the researcher, to evaluate long-term learning. • Data analysis strategy: The presence of spurious associations between demographic variables and learning scores will be evaluated using a chi-square test of independence and t-test analyses for independent samples. An analysis of covariance (ANCOVA) will be conducted on the posttest learning scores of the VR and non-VR groups with background stress and anxietyknowledge scores as covariates.

CONCLUSION
To the best of our knowledge, MIND-VR represents one of the first few published virtual reality content designed specifically to be used for psychological support for healthcare workers affected by the health crisis triggered by the COVID-19 pandemic. Once the ongoing pilot studies have been concluded, the data collected will allow to verify the usability of the first version of this virtual experience and to collect important data for the development of its final version. Besides, the collected data will permit to make more general reflections on the effect of virtual reality for psychoeducation in terms of short and long-term learning.
Interestingly, since MIND-VR has been developed not only in Italian but also in English, its use can be extended beyond Italian national borders and become a tool available free of charge worldwide for psychological support to doctors and nurses involved in the COVID-19 pandemic. Furthermore, this virtual reality psychoeducational experience on stress and anxiety can also be used once the COVID-19 emergency is over within prevention programs to prevent and alleviate stress and anxiety in healthcare personnel. In particular, MIND-VR can be included as a part of psychoeducation within cognitive-behavioral skills training for the medical personnel. This type of program is considered among the most effective approaches in reducing stress and anxiety among hospital staff (Clough et al., 2017;Alkhawaldeh et al., 2020), and it could benefit from integrating new technologies, including virtual reality (Richardson, 2017;Pallavicini and Bouchard, 2019;Weerasekara and Smedberg, 2019).
In addition to these aspects, other elements make MIND-VR potentially very relevant. First, this virtual psychoeducational content can be used not only with doctors and nurses but also with all other categories of people who need support in the management of stress and anxiety. For example, MIND-VR can be used within programs for the prevention and treatment of such conditions of mental suffering for all those people forced into isolation and/or quarantine due to COVID-19 infection. Also, in the next months, this psychoeducational virtual content will be tested in collaboration with an Italian hospital as a tool for psychoeducation on stress and anxiety within psychological support programs for families of patients with dementia, another typology of people greatly in need of new support tools for mental well-being.
Second, since MIND-VR was created to be very simple to use and to run on some currently more widespread, userfriendly, and low-cost HMDs (ie, Oculus Quest and Oculus Quest 2), such an experience could be also used autonomously by people and offered to provide psychological assistance remotely. This fact appears important because, due to the limitations imposed in many countries of the world in response to the COVID-19 pandemic emergency, many people have difficulty accessing face-to-face consultations and new tools appear necessary to increase the effectiveness 4 | The ad hoc questionnaire on the background knowledge of stress and anxiety will be adopted in Pilot Study 2.
Questionnaire on the background knowledge of stress and anxiety Part 1. Please indicate if ("yes"/"no") • Have you ever followed psychotherapy or stress and anxiety management programs? • Have you ever read a textbook on stress and anxiety? • Have you ever searched on the internet for information on stress and anxiety? • Since the COVID-19 outbreak, have you ever used remote psychological support programs (telephone or video)?
Part 2. Rate on a 7-point likert scale (1 " not at all," 7 "very much") your level of knowledge about • The differences between anxiety and stress • Causes of stress and anxiety • Symptoms of stress and anxiety • Techniques for the management of stress and anxiety TABLE 5 | The ad hoc questionnaire on the learning level of psychoeducational contents will be adopted in Pilot Study 2.
Questionnaire on the learning level of psychoeducational contents Part 1. Rate on a 7-point likert scale (1 "not at all", 7 "very much") the following statements • The content was mentally challenging • I perceived the topic of content as complex • I understand the information provided correctly • I enjoyed learning this way • In the future, I would like to learn in this way • I am interested in learning more about this topic • I perceived the content as stimulating • I felt motivated to learn the information of the therapies offered. remotely. Interestingly, in a recent study, it was reported that virtual reality-based remote therapy is more effective than treatments through video conferencing using programs such as Skype or Zoom, increasing the level of engagement, reducing dropout rates, and producing positive clinical outcomes (Pedram et al., 2020). Finally, given how few formative research studies and protocols are published for similar projects, the methodology used for MIND-VR could provide important knowledge for determining the feasibility of adopting virtual reality-based psychoeducational experience, expanding the range of virtual contents that can be created to address mental suffering. The methodology used for the development of MIND-VR, in fact, can also be used for the creation of other virtual psychoeducational experiences, providing important guiding elements in the creation of such virtual contents. While we adopted this specific process, others exist for developing interactive entertainment for behavior change (Mummah et al., 2016;Gotsis and Jordan-Marsh, 2018) and can serve as examples of the process in a field where there is a shortage of HCI professionals working in healthcare, as well as a shortage of creatives who are trained in UCD.

DATA AVAILABILITY STATEMENT
The original contributions presented in the study are included in the article. Further inquiries can be directed to the corresponding author.

AUTHOR CONTRIBUTION
FP conceived the work, wrote the first draft of the manuscript, and led the development of requirements, architectural paradigm, content, and evaluation protocol of MIND-VR. FM supervised the work in its scientific aspect. EO, SS, AP, and GV as highly experienced psychotherapists and psychologists, supervised the clinical features of MIND-VR. All the authors contributed to manuscript revision, read, and approved the submitted version of the manuscript.