TYPE Original Research PUBLISHED 19 April 2023 DOI 10.3389/fpsyt.2023.999656 Virtual self-conversation using OPEN ACCESS motivational interviewing techniques to promote healthy EDITED BY Marcela Tiburcio, National Institute of Psychiatry Ramon de la Fuente Muñiz (INPRFM), Mexico REVIEWED BY eating and physical activity: A Susan Persky, National Human Genome Research Institute (NIH), United States usability study Shiri Sadeh-Sharvit, Palo Alto University, Dimitra Anastasiadou 1,2*, Pol Herrero 1, United States Sam Liu, Julia Vázquez-De Sebastián 1,3, Paula Garcia-Royo 1, University of Victoria, Canada Bernhard Spanlang 4, Elena Álvarez de la Campa 4, *CORRESPONDENCE Mel Slater 4,5,6, Andreea Ciudin 7, Marta Comas 7,8,9, Dimitra Anastasiadou J. Antoni Ramos-Quiroga 1,10,11,12 and Pilar Lusilla-Palacios 1,10,11,12 dimitra.anastasiadou@uab.cat SPECIALTY SECTION 1 Psychiatry, Mental Health and Addictions Research Group, Vall d’Hebron Research Institute, Barcelona, This article was submitted to Spain, 2 Department of Clinical and Health Psychology, Autonomous University of Barcelona, Barcelona, Digital Mental Health, Spain, 3 RE-FiT Barcelona Research Group, Vall d’Hebron Research Institute and Parc Sanitari Pere Virgili, a section of the journal Barcelona, Spain, 4 Virtual Bodyworks S.L., Barcelona, Spain, 5 The Institute of Neurosciences of the Frontiers in Psychiatry University of Barcelona, Barcelona, Spain, 6 Department of Clinical Psychology and Psychobiology, University of Barcelona, Barcelona, Spain, 7 Endocrinology and Nutrition Department, Vall d’Hebron RECEIVED 21 July 2022 University Hospital, Barcelona, Spain, 8 Vall d’Hebron Research Institute (VHIR), Universitat Autònoma de ACCEPTED 14 February 2023 Barcelona (VHIR-UAB), Barcelona, Spain, 9 Centro de Investigación Biomédica en Red de Diabetes y PUBLISHED 19 April 2023 Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III, Madrid, Spain, 10 Psychiatry Department, Vall d’Hebron University Hospital, Barcelona, Spain, 11 Department of Psychiatry CITATION and Legal Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain, 12 Biomedical Network Anastasiadou D, Herrero P, Vázquez-De Research Centre on Mental Health (CIBERSAM), Barcelona, Spain Sebastián J, Garcia-Royo P, Spanlang B, Álvarez de la Campa E, Slater M, Ciudin A, Comas M, Ramos-Quiroga JA and Lusilla-Palacios P (2023) Virtual self- conversation using motivational interviewing Introduction: We aim to examine the usability of a Virtual Reality (VR) platform, techniques to promote healthy eating and physical activity: A usability study. called ConVRSelf, which has been designed to address the needs of People Living Front. Psychiatry 14:999656. With Obesity (PLWO). doi: 10.3389/fpsyt.2023.999656 Methods: Fourteen participants with a desire to eat healthier and exercise more COPYRIGHT (6 normal weight and 8 PLWO; Mean age=41.86, SD=13.89) were assigned to the © 2023 Anastasiadou, Herrero, Vázquez-De Sebastián, Garcia-Royo, Spanlang, Álvarez de la experimental group (EG) or the control group (CG). EG participants, after being Campa, Slater, Ciudin, Comas, Ramos-Quiroga trained on motivational interviewing skills, engaged in a virtual self-conversation and Lusilla-Palacios. This is an open-access using embodiment and body swapping techniques, which aimed to normalize and article distributed under the terms of the Creative Commons Attribution License (CC BY). resolve their ambivalence to change lifestyle habits. CG participants, embodied The use, distribution or reproduction in other in their virtual bodies, participated in a pre-established discourse with a virtual forums is permitted, provided the original counselor giving them psychoeducational advice about how to change lifestyle author(s) and the copyright owner(s) are credited and that the original publication in this habits. A mixed-methods design was used, involving a semi-structured interview journal is cited, in accordance with accepted and self-report questionnaires, including readiness to change habits (Readiness academic practice. No use, distribution or Rulers), body ownership (Body Ownership Questionnaire, BOQ), and system reproduction is permitted which does not comply with these terms. usability (System Evaluation Questionnaire, SEQ). Thematic content analysis was carried out for qualitative data while statistical data analysis was carried out using SPSS 20.0. Results: Participants from both groups showed high readiness to change lifestyle (Readiness Rulers) before engaging with the virtual experiences, which was maintained at the same level after the interventions and their scores on the SEQ and BOQ were satisfactory. Regarding qualitative information obtained from the interviews, almost all participants found the VR experience to be novel, interesting, and enjoyable. A higher acceptability was observed among PLWO from the EG than normal weight participants from the same group, a promising finding for the Frontiers in Psychiatry 01 frontiersin.org Anastasiadou et al. 10.3389/fpsyt.2023.999656 ConVRSelf platform, which had been specifically designed to address the needs of PLWO. Conclusion: The ConVRSelf system is well-accepted by participants and is ready to be tested with PLWO in a clinical setting. KEYWORDS obesity, virtual reality, psychological treatment, embodiment, usability, motivational interviewing Introduction The research reported in this paper is part of an overall attempt to respond to these challenges by integrating some elements of the MI Obesity is a complex and chronic disease with multiple adverse theoretical framework (6) in a VR context to treat obesity. This takes effects on the individual’s physical and psychological health (1). place in the European project SOCRATES. Guidelines support psychological and behavioral weight management The study uses a VR platform, called ConVRSelf (13, 14), interventions as gold standard treatments for obesity (2). However, specifically developed for PLWO. One of the main advantages of using these treatments often fail in the long-term; in fact, nearly half of VR is that in such an environment, the person’s real body can patients return to their original weight within 5 years of treatment (3). be apparently substituted by a life-sized virtual body. Hence, when One of the factors associated with this may be the low attention paid participants wear a Head-Mounted display and look down toward in therapy to the motivating factors underlying adherence (4). their bodies, they see a virtual body coincident in space with their real Another factor may be the limited addressment of the weight bias body. Also, through real-time tracking of their limbs, when they move internalization, often produced among this population, which further their real body, the virtual body can be programmed to move contributes to increased morbidity and mortality independently of correspondingly and synchronously. The technological means through Body Mass Index (BMI) (5). which the person is endowed with a life-sized virtual body that In recent decades, the low adherence to obesity treatment has apparently substitutes their real body is called “embodiment.” been addressed by using Motivational Interviewing (MI) techniques Particularly with the ConVRSelf platform, participants can see their (6, 7). MI can be understood as “a collaborative, goal-oriented method virtual body that looks like their own body by looking directly down of communication between patient and healthcare professional with toward themselves or by seeing it reflected in a virtual mirror so that particular attention to the language of change. It is designed to the mirror will reflect back the avatar they embody. The perceptual strengthen an individual’s motivation for and movement toward a consequence of embodiment is “body ownership,” the perceptual specific goal by eliciting and exploring the person’s own reasons for illusion that participants can experience when they feel that the virtual change within an atmosphere of acceptance and compassion” (8). body is their body even though they know that this is not the case. Research has shown that it is feasible to integrate MI techniques with This type of body ownership was demonstrated in a classic paper behavioral and psychological interventions for obesity and that these where visual-tactile synchrony was used to incorporate a rubber hand interventions have the potential to improve health-related outcomes, into the body representation of participants through synchronous especially in the long term (9). tactile stimulation of the seen rubber hand and the out-of-sight Hence, following the MI theoretical framework, psychological corresponding real hand (15). Whole-body ownership of a virtual treatments for obesity should normalize the ambivalence that People body seen from a first-person perspective was demonstrated by video- Living With Obesity (PLWO) often experience when starting their based VR (16), and computer graphics-based VR (17), and it has been change process toward a healthier lifestyle, and then help them to repeatedly demonstrated ever since (18–21). In addition, it has been explore their own reasons for change in line with their needs and shown that the avatar embodied does not have to look, necessarily, like values. Finally, psychological treatments should also promote the self- the actual person for there to be a strong illusion of body ownership efficacy of this population, which may be hindered due to the (21). Finally, a further consequence of such embodiment in bodies increased weight bias internalization, among other factors (5, 10). that are quite different from the person’s own body is that it can lead Besides, COVID-19 has shown us the need for personalized to changes in attitudes, behaviors, and cognition. For instance, the treatments, adapted to unforeseen circumstances and special contexts, above-mentioned papers illustrate changes in implicit racial bias and and has been a tipping point for the implementation of eHealth also improvement in performance in a cognitive test when embodied interventions (11), also for the treatment of obesity (10). In particular, as Albert Einstein. the use of Virtual Reality (VR) with embodiment techniques following The ConVRSelf platform employs embodiment and body Cognitive Behavioral Therapy (CBT) principles has promising swapping techniques for self-counseling. Participants, once being preliminary effectiveness in the treatment of eating disorders (ED) embodied in their look-alike avatar and having achieved a sense of and obesity (12). However, some of the above-mentioned body ownership, they found themselves in front of a counselor sitting psychological factors associated with this condition (i.e., ambivalence across the table. First, participants explain their problem to the to change, internalization of weight bias) have not been properly counselor, and once finished, they are embodied in the counselor’s addressed in these treatments, which essentially deliver the same CBT body and can see and hear their own look-alike avatar explain the in a VR environment. problem (this change of avatars is called the body swapping Frontiers in Psychiatry 02 frontiersin.org Anastasiadou et al. 10.3389/fpsyt.2023.999656 technique). In this case, while embodied as the counselor, if they look Experimental group down toward themselves, they will see the counselor’s body, and similarly, this body will be reflected in a virtual mirror. Now, as Participants from this group were embodied alternatively in their counselor, they can respond to their look-alike avatar by making look-alike avatar and in their counselor’s avatar. To create the avatars, comments or suggestions about the problem. After this, they swap participants’ whole-body photos, as well as information about their back to their original (self) body and can see and hear the counselor body weight and height, were required. For the counselor’s avatar, respond to their problem. Continuing in this way, they can continue participants were able to choose among different avatar options that a self-conversation from the two embodied perspectives—as were sex-matched (young normal weight, old normal weight, young themselves and as the counselor. overweight, and old overweight). Then, participants engaged in a Virtual embodiment has been used extensively in orthopedic virtual self-conversation aiming at helping them understand their own rehabilitation, pain reduction, ED and obesity (22–26), while motivation and ambivalence to eat healthier and exercise more. By embodiment and body swapping techniques have been shown to using the body swapping technique, participants were embodied be effective in helping people solve personal problems through a alternately in their own virtual representation, who explained their virtual self-conversation (13, 14). problem to a virtual counselor, and in their counselor’s body, who tried The objective of the present study is to examine the usability of the to advice on this problem. The goal was for them to better understand ConVRself platform among PLWO and normal weight participants. their process of change, to be more compassionate, and more This platform has been specifically developed for PLWO to help them competent counselors for themselves during the virtual experience. To address the following challenges related to their condition: first, better guide this virtual self-conversation, participants from the EG normalize and resolve their ambivalence to change, second, better received an intensive training on MI skills (6) before being exposed to understand and address the impact of weight bias internalization, and the VR. The basic goal of the training was to help participants organize third, increase their self-efficacy by setting realistic goals in line with their future self-conversation so they would be able to guide themselves their own values. There were two groups of participants: the through a discourse of change based on their values and interests. More Experimental Group (EG) engaged with a virtual self-conversation details about the contents of the training can be found in the protocol using the embodiment and body swapping elements of ConVRSelf, study (27) while the behavioral change techniques used in the whereas the Control Group (CG) listened to a virtual pre-established intervention can be found in Table 1. discourse with only the embodiment element. With the present usability study, we hypothesize that the VR platform in its 2 versions Control group (embodiment + body swapping vs. only embodiment) would be well- Participants from this group were embodied in their look-alike accepted by participants from both groups, with higher levels of avatar, similarly to what has been previously described for the EG, and usability perceived by PLWO compared to normal weight participants. participated in a “pre-established discourse” provided by a counselor We also hypothesize that participants of the EG would increase more chosen by them (as previously described for the EG), who asked them their motivation to enhance with healthy lifestyle habits through the about the perceived barriers for engagement with a healthier lifestyle, motivational self-conversation compared to the CG, while the same and gave pre-recorded practical recommendations about how to achieve levels of body ownership would be expected between groups. This is a healthier and happier life, in terms of healthy eating and physical activity. a preliminary study before the start of the SOCRATES clinical trial, which is running throughout 2022 and whose protocol has been published recently (27). Participants Fourteen participants (6 normal weight and 8 PLWO; Mean Methods age = 41.86, SD = 13.89), with a desire to make positive lifestyle changes in terms of eating healthier and exercising more, were recruited for the Design usability study from the Vall d’Hebron University Hospital, during the months of August and November 2021, after having read an informative This is a quasi-experimental between-groups design with a single leaflet about the SOCRATES project and having expressed their interest factor and two treatment levels: EG vs. CG. There were two assessment to be involved. Participants were assigned to one of the two treatment time-points—at baseline (T0) and post-intervention (T1). A mixed- conditions. The EG comprised 3 normal weight participants and 5 methods design was used, involving a semi-structured interview and PLWO, and the CG 3 normal weight participants and 3 PLWO. PLWO self-report questionnaires. had BMI ≥ 30 kg/m2 and ≤45 kg/m2. Inclusion criteria for the whole sample were (a) age between 18 and 65 years, (b) minimal digital skills, (c) oral and written understanding of the Spanish language, and (d) Procedure agreement to sign the informed consent to participate, while exclusion criteria were (a) presence of non-stabilized severe mental disorder, (b) Both participants from the EG and CG tried the Experiment 1 auditory or visual complications, (c) intellectual disability or any major “Embodied discussion about the problem and solutions” of the ongoing illness seriously affecting cognitive performance, and (d) history of SOCRATES Randomized Controlled Trial (RCT), in 2 different epilepsy. For the PLWO group, 2 additional exclusion criteria were versions: the EG experienced a scenario with both the embodiment established as follows: (a) BMI > 46 kg/m2, (b) not receiving ambulatory and body swapping elements integrated into the virtual experience, treatment at the Vall d’Hebron University Hospital, and (c) presence of and the CG experienced only the embodiment element. an ED at least for 2 years. All inclusion and exclusion criteria were Frontiers in Psychiatry 03 frontiersin.org Anastasiadou et al. 10.3389/fpsyt.2023.999656 TABLE 1 Summary of the motivational interviewing micro-skills to elicit behavioral change1. Open questions These types of questions make the person reflect and elaborate on their discourse. In contrast to Closed questions, which usually have a short answer and the variety of answers is limited, Open questions help the counselor understand the person’s internal frame of reference given that the answers the patient can provide are richer. Affirming The objective of this micro-skill is to accentuate the positive parts of the discourse. To affirm is to clarify and acknowledge what is good. Affirmation also means to indicate the client’s strengths and intentions. Reflecting Reflective statements made by the counselor allow the patient to listen again to what he/she is expressing in different words to maintain a discourse of change. It must be necessarily selective, in that one chooses what to reflect from all the information the patient has provided. The main objective is to highlight what the counselor thinks is important to the patient. Summarizing They are understood as reflections that compile different kinds of information from the patients. Hence, patients not only listen to themselves describing their experiences, but they also hear reflected what they said in order to encourage change. Elicit-Provide-Elicit This is a sequence for information exchange that respects the client’s expertise and autonomy. Before giving any information to the patient, MI encourages to first acknowledge what is the patient’s knowledge, and also to ask for permission to give new information. Decisional balance This evaluation helps the client resolve ambivalence by weighing the pros and cons during the decision process. To do so, the patient has to provide his/her own reasons by giving equal exploration to both pros and cons for doing such a change. Readiness Rulers These are scales ranging from 1 to 10 that evaluate “importance,” “confidence,” and “readiness” to promote change. For “importance,” it is meant the perceived need the person has for change; for “confidence,” the evaluation is about the patient’s self-efficacy; and for “readiness,” the patient evaluates their preparation to mobilize toward change. For the Usability study, these variables are measured in terms of (a) achieving a healthy weight and (b) exercising more. Miller W, Rollnick S. La entrevista motivacional: ayudar a las personas a cambiar. Barcelona: Paidós; 2015. 1 assessed through an initial clinical interview by clinical researchers of acceptance, and security of use in VR platforms, was administered the team. More detailed information about this procedure can be found at T1 (30). Thirteen questions of the SEQ are based on a 5-point in the publication of the RCT protocol (27). Likert scale plus a last open-ended question offering participants the possibility to add comments if they wish. The total score of the questionnaire ranges from 13 (poor suitability) to 65 Assessment measures (excellent suitability). For the specific purposes of the present study, the word “rehabilitation” of Q11 was replaced by “obesity Sociodemographic and clinical variables treatment.” Preliminary results from an initial attempt to validate Information about participants’ age, biological sex, level of the SEQ by Gil-Gómez and colleagues showed an acceptable education, marital and employment status, clinical information internal consistency of the questionnaire (Cronbach’s including the presence of any physical or mental health problem, alpha = 0.7) (30). as well as the fulfillment of the inclusion criteria, were assessed at baseline (T0) through a semi-structured interview by researchers Body Ownership Questionnaire of the SOCRATES team at Vall d’Hebron Research Institute At the end of the VR exposure (T1), participants completed a (VHIR). The weight of each participant was measured by trained subjective rating of the illusion of body ownership through a 7-point staff, at the same time of the day for all participants, and using a Likert scale, where −3 meant “Strongly disagree” and + 3 “Strongly digital scale while the height was informed by participants. Finally, agree.” Questions were taken from a previous study evaluating BMI was calculated as weight in kilograms divided by height in ConVRSelf (14), and are the following: “Even though the body I see square meters [W (kg)/H (m2)]. might not physically look like me, I feel that the virtual body I see when I look down towards myself is my body” (body ownership-look Readiness Rulers down); “Even though the body I see might not physically look like me, Readiness Rulers (RR) (28) are Visual Analog Scales ranging from I feel that the virtual body I see reflected in the mirror is my body” 1 to 10 that assess “importance,” “confidence,” and “readiness” to (body ownership-mirror); “I feel that the movements of the virtual change. For the present study, only the Readiness to change variable body are caused by my own movements” (body ownership- was measured in terms of (a) achieving a healthy weight and (b) movements); “The body I see in the virtual world physically looks like exercising more, before the virtual experiment (T0) and just after the me” (self-recognition). For the EG only, the same questions were experiment (T1) (28). Lower numbers represent “not prepared” to asked for both the participant’s embodiment on the self-side and the change, scores of 4–6 represent ambivalence in terms of “somewhat counselor’s side. prepared to change,” and higher numbers represent “very prepared to change” or ongoing attempts of changing. The RR have been used in Users’ experience addiction studies showing good psychometric properties (29). A brief interview was carried out after the VR exposure (T1) to assess the satisfaction of participants with the VR experience and Suitability Evaluation Questionnaire acceptability of the ConVRSelf tool, including questions related to their The Suitability Evaluation Questionnaire (SEQ) (30), which experience using the self-conversation technique, in a VR context, to is a 14-item questionnaire designed to measure satisfaction, cope with their condition. Frontiers in Psychiatry 04 frontiersin.org Anastasiadou et al. 10.3389/fpsyt.2023.999656 Data analysis Readiness to change Statistical analyses of the data were carried out using SPSS A Wilcoxon signed-rank test showed that the virtual experiment 20.0 statistical software. Non-parametric tests were performed with ConVRSelf did not elicit a statistically significant change in due to the small sample size. Descriptive data regarding Readiness to exercise more (Z = −0.74, p = 0.461, r = 0.198) and participants’ sociodemographic and clinical characteristics, Readiness to lose weight (Z = −1.19, p = 0.236, r = 0.318) among the readiness to change, body ownership, and usability were whole sample. Indeed, median RR score was 8.0 both at T0 and T1 for calculated, and differences between groups (normal weight vs. the Readiness to exercise more and Readiness to lose weight variables. PLWO and CG vs. EG) on each sociodemographic and clinical When we split the sample into 2 groups (EG, CG), differences between variable were assessed with a Chi-square or Mann-Whitney U test. T0 and T1 in RR were still no significant [EG: Readiness to exercise A Wilcoxon signed-ranked test was used to examine changes in more (Z = 0.00, p = 1.000, r = 0), Readiness to lose weight (Z = −0.82, participants’ readiness to change (through RR) in terms of p = 0.414, r = 0.290); CG: Readiness to exercise more (Z = −1.00, Exercise more and Lose weight, for the whole sample and each p = 0.317, r = 0.408), and Readiness to lose weight (Z = −0.82, p = 0.414, group separately (EG and CG). A Mann-Whitney U test was r = 0.335)]. performed to explore differences between EG and CG on the SEQ and Body Ownership Questionnaire (BOQ). Additionally, for any sociodemographic result that was statistically significant for EG Usability and satisfaction and CG, an ANOVA with Bootstrapping (1,000 samples) was performed with such for the variable as covariate for SEQ and Participants’ scores on the SEQ revealed a good usability of the BOQ. Finally, a Spearman’s correlation was used to analyze the virtual platform (M = 51.31; SD = 13.38), while a Mann–Whitney U relationship between participants’ BMI and SEQ total score. To test showed that there were no significant differences between the EG obtain the value of the effect size for the Mann–Whitney U test and the CG on the SEQ scores [U(NEG = 8, NCG = 6,) = 22.000, Z = −0.26, |Z | we calculated the r effect size as r = n . For ANOVA with p = 0.795, r = 0.069]. Regarding participants’ responses on individual bootstrapping, we interpreted eta squared (η2). According to SEQ items, the only significant difference with large effect was for item Cohen criteria, r = 0.1/η2 = 0.01, r = 0.3/η2 = 0.06, and r = 0.5/ 11 (“¿Do you think this treatment will be useful for you?”) [U (NEG = 8, η2 = 0.14 are small, medium, and large effect, respectively (31). NCG = 6) = 3.500, Z = −2.83, p = 0.005, r = 0.756], on which higher Statistical significance was set at p < 0.05. scores were found among participants from the EG (Mdn = 5) Thematic content analysis was performed to analyze the compared to the CG (Mdn = 3). qualitative data collected from T1 interviews with the EG. First, members of the research team independently read the transcripts of the 14 interviews and sought to categorize the available information Body ownership in terms of perceived advantages and disadvantages of the VR experience, separately for the EG and the CG. Categories followed a Non-statistically significant differences in the BOQ scores were previous classification carried out by a member of the team (32). In shown between treatment conditions, except for the “body ownership- case of disagreement between the assessors, consensus was achieved mirror” item (“Even though the body I see might not physically look like through discussion. No software or tool was used during this process. me, I feel that the virtual body I see reflected in the mirror is my body”), Translations from Spanish to English of all qualitative data from the in which the EG (Mdn = 3) reported higher body ownership when interviews was carried out by a bilingual research assistant. Finally, the looking at the mirror than the CG (Mdn = 0) [U(NEG = 8, most representative examples for each theme for the EG were collected NCG = 6) = 9.000, Z = −2.07, p = 0.038, r = 0.553]. Figure 1 shows BOQ from the transcripts after discussion among researchers of the team. scores between EG and CG, separately for normal weight participants and PLWO. Results Sex as a covariate Sociodemographic information One-Way ANOVA with Bootstrapping (1,000 samples) with The comparisons of sociodemographic and clinical characteristics Sex as covariate was performed for all tests when comparing between normal weight and PLWO participants are illustrated in between EG and CG. The only deviation from the previously Table 2. It is worth mentioning that the majority of normal weight reported results was found for “body ownership-mirror” item of participants (83.3%) had university degree studies, while the majority the BOQ, in which, in opposition to previous analysis, no of PLWO (87.5%) were educated up to “Intermediate/high secondary significant results were reported between groups [F(1, 11) = 2.44, education” level [χ2(2) = 10.60, p = 0.031]. Also, a Mann–Whitney U test p = 0.146, η2 = 0.182]. reported significant differences in the BMI between normal weight participants and PLWO (Z = −3.10; p = 0.002), in Age (Z = −2.33; p = 0.020), and educational level [χ2(2) = 10.60, p = 0.031]. Same SEQ-BMI correlation comparisons were also performed between EG and CG. No differences were shown between groups except for variable Sex [NEG (Men = 1; As shown in Figure 2, Spearman’s correlations showed a strong Women = 7) NCG (Men = 5; Women = 1)] [χ2(1) = 7.02, p = 0.008]. positive correlation between the SEQ Total score and the BMI [r(6) Frontiers in Psychiatry 05 frontiersin.org Anastasiadou et al. 10.3389/fpsyt.2023.999656 TABLE 2 Sociodemographic Characteristics of Participants at Baseline. Normal weight (N = 6) PLWO (N = 8) Z; p M SD M SD Age (years) 51.1 13.3 34.9 10.1 –2.33; 0.02 Mean age of treatment − − 29.5 12.2 − onset (years) Treatment duration − − 6.1 3.7 − (months) BMI 24.1 2.5 42.9 4.3 −3.10; 0.002 Normal weight (N = 6) PLWO (N = 8) Full sample (N = 14) X2; p N % N % N % Sex 0.22; .640 Female 3 50 5 62.5 8 57.1 Male 3 50 3 37.5 6 42.8 Nationality 0.73; .393 Spanish 5 83.3 5 62.5 10 71.4 Latin-American 1 16.7 3 37.5 4 28.5 Marital Status 3.28; .194 Single 3 50 5 62.5 8 57.1 Married/partnered 3 50 3 37.5 6 42.8 Educational level 10.60; .031 Intermediate 1 16.7 3 37.5 4 28.5 secondary education/ vocational training Intermediate/high 0 0 4 50 4 28.5 secondary education University or 5 83.3 1 12.5 6 42.8 postgraduate Employment 6.12; .190   Student 0 0 1 12.5 1 7.1 Part-time job 0 0 2 25 2 14.3 Full-time job 5 83.3 2 25 7 50 Sick leave 0 0 2 25 2 14.3 Retired 1 16.7 1 12.5 2 14.3 Physical illness 2.43; .119 Yes 2 33.3 6 75 8 57.1 No 4 66.6 2 25 6 42.8 Mental illness 1.66; .198 Yes 1 16.6 4 50 5 35.7 No 5 83.3 4 50 9 64.3 Physical symptoms - Epilepsy 1 16.7 0 0 1 7.1 Type 2 diabetes 1 16.7 0 0 1 7.1 Hypertension 0 0 1 12.5 1 7.1 Respiratory problems 0 0 2 25 2 14.3 Thyroid 1 16.7 1 12.5 2 14.3 Gastritis 0 0 1 12.5 1 7.1 (Continued) Frontiers in Psychiatry 06 frontiersin.org Anastasiadou et al. 10.3389/fpsyt.2023.999656 TABLE 2 (Continued) Normal weight (N = 6) PLWO (N = 8) Full sample (N = 14) X2; p N % N % N % Fatty liver disease 0 0 1 12.5 1 7.1 Choletithiasis 0 0 1 12.5 1 7.1 Sleep apnea 0 0 1 12.5 1 7.1 Mental symptoms Anxiety, Panic 1 16.7 2 25 3 21.4 attacks Depression 0 0 2 25 2 14.3 Insomnia 1 16.7 0 0 1 7.1 ADHD 0 0 1 12.5 1 7.1 Bold values indicate statistically significant differences between healthy participants and PLWO. M = mean score, SD = standard deviation, BMI =Body mass index, ADHD = Attention deficit hyperactivity disorder. =0.916, p = 0.001] for participants from the EG, while this correlation with the change of roles”; “being patient or counselor… I was lost was no significant for the CG [r(4) = − 0.750, p = 0.086]. and I did not know if I had to talk as a patient or counselor”) and 1 highlighted the importance of receiving more previous training on the body swapping technique (“To use it properly, I consider it Qualitative results essential to receive previous training on the correct use of the platform and also on how to correctly formulate questions for the The qualitative analysis focused on results from the interviews self-conversation”). carried out with participants from the EG and the CG right after their Apart from being useful, 3/8 participants claimed that the virtual experience (T1). Participants´ responses were categorized into platform was intuitive and easy to use from the beginning (see different key themes that were then classified into different domains, “Perceived Ease of Use,” Table 3) and the rest claimed that managing following previous research on mHealth adoption barriers and the platform was not easy until becoming familiarized with it (i.e., “At facilitators carried out by a member of the research team (32). The list the beginning I needed some instructions and guidance from the of domains and themes together with the perceived advantages and therapist but then it was easy for me to use the platform”). As regards disadvantages of the platform for the EG only is shown in Table 3. the “Negative perception of ease of use,” some participants (5/8) Finally, the perceived advantages and disadvantages of the virtual showed discomfort when using the controllers at the beginning of the experience perceived by participants of the CG will be reported in the experience highlighting the need to improve their sensitivity (i.e., “I last part of this section. would improve the sensitivity of the controllers, as it was difficult for me For the EG, regarding the advantages of the “Perceived to use them properly and to press the buttons that I was asked to usefulness” theme, all participants (8/8) agreed that the VR platform continue with the experience correctly”). Besides, a left-handed enhanced their motivation to change regardless of their health participant also mentioned that the platform was not well-adapted to condition (i.e., “It makes you think and say to yourself: Wow, this is her needs (i.e., “Being left-handed was quite challenging because the something I have to do,” “It helped me a lot because I realized that my platform thought I wanted to push the Exit button when I was just rising problem has a solution”). Also, 6/8 participants considered my right arm”). ConVRSelf as a new source that helped them to understand their As regards the participants’ perceived advantages concerning the reasons for change and express them through the “Change Talk” (6) design of the platform (see “Design and Personalization,” Table 3), (i.e., “It helped me to reflect and be more aware of the steps that most participants (7/8) considered that the virtual environment was I must follow to achieve my goals in a more concrete and tangible relaxing, calm, and attractive. They also agreed upon the fact that an way,” “It confronts you with your goals and helps you to better appealing environment helped them to better communicate with organize your ideas”). Besides, all participants (8/8) considered that their counselor and concentrate on the task (i.e., “I found the virtual ConVRSelf enriched their perspective on the problem and gave environment attractive and cosy, and the fact that it was empty was them more self-confidence (i.e., “Sometimes, it is hard to listen to the relaxing and promoted my concentration”). Remarkably, 3/5 of PLWO others’ advice, and we tend to trust our own beliefs more. Contrary to valued positively the resemblance of the embodied virtual avatar with this, this platform is very useful because it helps you listen to your their real self (i.e., “The avatar was very similar to me, it wore the same own advices as if these were given from the outside”; “I have been able shirt, and the face was as small as mine”). As regards participants’ to immerse myself into the virtual experience, gain confidence, and perceived disadvantages in relation to the platform’s design and not feel ashamed when explaining my problem to someone I did personalization (see “Problems with the design of the platform and not know”). Lack of personalization,” Table 3), 1/3 of normal weight participants Regarding the disadvantages of the usefulness theme (see found the virtual environment quite unrealistic for being a counselor’s “Negative perception of usefulness,” Table 3), 2 normal weight office (i.e., “I would prefer a more realistic virtual environment”). participants agreed on the fact that changing perspectives (body Besides, 1/3 of normal weight participants and 1/5 of PLWO did not swapping) may be confusing and distracting in the short-term recognize themselves in the avatar they embodied (“The look-alike (i.e., “…I felt disconnected and lost fluency in my argumentation,” avatar did not look like me; it was fatter than me, and this was “During the self-conversation, I felt disconnected and a bit stressed annoying during the experience”). Frontiers in Psychiatry 07 frontiersin.org Anastasiadou et al. 10.3389/fpsyt.2023.999656 TABLE 3 Perceived advantages and disadvantages of the VR experience by normal weight participants (NW) and patients (P) from the Experimental Group. ADVANTAGES Domain Key themes Examples of NW´ statements Examples of P’ statements Characteristics of Perceived ease of use - “At the beginning I needed some instructions and guidance - “The platform was very intuitive and easy to use”. the VR platform from the therapist, but then it was easy for me to use the - “It was easy to use but I would rather use it with my glasses platform” on because it was blurry” Perceived usefulness - “It confronts you with your goals and helps you to better - “With this platform I have been able to give myself advice organize your ideas” more easily than when I have a problem and I have to think - “It helped me to reflect and be more aware of the steps I must how to solve it” follow to achieve my goals in a more concrete and tangible way” - “It makes you think and say to yourself: “Wow, this is - “I have now set a day to take my first step towards the change something I have to do” I want to do” - “Sometimes, it is hard to listen to the others’ advice, and - “I would recommend the platform to a friend who wants to we tend to trust more our own beliefs. Contrary to this, this make any lifestyle change” platform is very useful because it helps you listen to your own - “I have been able to immerse myself into the virtual experience, advices as if they were from the outside” gain confidence, and not feel ashamed when explaining my - “I had the chance to put myself in the counselor’s shoes and problem to someone I did not know” talk to me the way I would like to be talked to” - “ConVRself can be a time- and cost-saving platform to be used - “What I enjoyed the most is having the chance to make as a complementary tool to face-to-face treatment” questions I would myself love to hear” - “Sometimes it is better to train people in this way, rather than - “I became fully aware of my overweight” to take them to the real therapeutic office” - “Together with psychological and nutritional supervision, I think this platform could help me changing my lifestyle” - “It helped me a lot because I realized my problem has a solution” - “I would recommend this platform to my partner, who has some emotional problems. Design and - “I found the virtual environment attractive and cosy, and at - “The virtual environment was very relaxing” Personalization the same time, the fact that it was empty was relaxing and - “The avatar was very similar to me, it wore the same shirt promoted my concentration” and the face was as small as mine” - “I liked the personalized avatars” - Very intuitive platform and very relaxing environment” - “I found the counselor really kind and empathetic" - “I really like the avatar’s body and voices, and the environment was very relaxing” DISADVANTAGES Domain Key themes Examples of NW’ statements Examples of P´ statements Characteristics of Negative perception - “It took a long time for the psychologist who was accompanying - “I spent too much time trying to push the buttons to make the VR platform of ease of use me during the experience to do the initial calibration” the experience work as it should” - “I would improve the sensitivity of the controllers, as it was - “Being left-handed was quite challenging because the difficult for me to use them properly and to press the buttons platform thought I wanted to push the Exit button when that I was asked to continue with the experience correctly” I was just rising my right arm” Negative perception - “I felt impatient when having to listen to myself twice. I felt - “It took me too much time to push the buttons. Sometimes of usefulness disconnected and I lost fluency in my argumentation” I disconnected myself from the experience” - “During the self-conversation, I felt disconnected and a bit stressed with the change of roles (being patient or counselor). I was lost and did not know if I had to talk as a patient or counselor” - “To use it properly, I consider it essential to receive previous training on the correct use of the platform and also on how to correctly formulate questions for the self-conversation” Problems with the - “I would prefer a more realistic virtual environment” - “My avatar was different. It was slimmer and the chest was design of the - “The self-avatar did not look like me; it was fatter than me, more compact” platform and this was annoying during the experience” - “Avatars were unrealistic. They looked like cartoons” (Continued) Frontiers in Psychiatry 08 frontiersin.org Anastasiadou et al. 10.3389/fpsyt.2023.999656 TABLE 3 (Continued) ADVANTAGES Domain Key themes Examples of NW´ statements Examples of P’ statements Lack of - “It would have been better to personalize the background of the personalization virtual environment. For instance, I would have liked it if I could choose among different backgrounds, such as the therapist’s office or a beach. This could increase my introspection capacity” - “It would have been nice to be able to regulate the luminosity of the virtual environment according to each user’s preferences” Individual factors Age, gender, and - “I think that elderly people will have more problems in using education the platform” Characteristics of Negative perception - “The HMD was heavy and uncomfortable to wear after a long the Oculus Quest 2 of ease of use time” - “I had to wait after the experience because the area around my eyes was red from the pressure of the device” - “My lenses were dirty, and I wonder whether they had been properly disinfected before I used them for Covid-19” As regards the participants’ perceived disadvantages related to the treatment (40, 41). However, what those studies normally offer is an ease of use of the Meta Quest 2 device (summarized in the extension of face-to-face CBT techniques for use in a VR context “Characteristics of the Oculus Quest 2” domain, Table 3), all normal [for instance, behavioral modeling (36), food exposure with weight participants (3/8) identified some disadvantages related to the response prevention, distraction (39), or exposure to negative body- weight of the Head-Mounted display, concerns related to the proper related experiences (40, 41)]. Some of the psychological factors disinfection of the device, and some discomfort felt in their eyes after associated with obesity, such as the ambivalence to make lifestyle the experiment. Finally, a normal weight participant (1/3) suggested changes or the internalization of weight bias, have not been properly that the platform is not adapted to the needs of the elderly and addressed in previous studies using VR platforms. In contrast, our expressed her concerns regarding the digital gap for them (see study focused on the specific psychological needs of this population “Individual factors” domain). in relation to the new technology they were expected to use, and Lastly, regarding the CG, the main advantages reported were having explored their perceived facilitators or barriers to using the VR an enjoyable experience, which made them increase the awareness of platform, or their own suggestions for improvement. The long-term their condition and verbalize their concerns (Normal weight: “It made aim of the SOCRATES project is to evaluate the efficacy of me more aware of my habits”; PLWO: “Verbalizing my thoughts was ConVRSelf for PLWO, through a RCT, after having carried out the relieving and made me increase my awareness of my condition”), the ease present usability study. of use of the platform (PLWO: “It was very easy to use”), the attractiveness Participants from both groups showed high readiness to change of the virtual environment, and the empathetic attitude of the counselor lifestyles before engaging with the virtual experience, which was (Normal weight: “What I enjoyed the most was the environment, in maintained at the same level after the intervention. It is interesting to particular the sky, and the counselor sympathy”). On the other hand, the note that PLWO were already attending the Endocrinology and most recurrent criticism was the lack of personalization of the virtual Nutrition Department of the Vall d’Hebron University Hospital to environment and the lack of the opportunity to interact with the seek treatment, something that may explain why they showed high counselor (Normal weight: “The platform was very static and not very motivation to engage with a healthier lifestyle even before the virtual personalized”; PLWO: “I missed a more personalized experience that experiment. This remarkable finding should be explored in more would allow me to have a more intuitive dialogue with my therapist”). detail in the ongoing RCT with a larger sample size and longer follow-up assessments. In addition, to say that someone is ready to change is not the same as being confident about change, wanting to Discussion change, or making a commitment to change. In the RCT, these multifaceted elements of motivation will be differentiated and The objective of the present study was to examine the usability measured separately. On the other hand, all participants revealed of ConVRSelf, a VR platform that has been specifically designed to good usability of the platform, with no significant differences in the address some of the psychological needs of PLWO, by using total SEQ scores between the EG—with the body swapping element— embodiment and body swapping techniques. One of the main and the CG—without body swapping. Similarly, in a previous study challenges for experts working in the area of eHealth is to make the using ConVRSelf with healthy volunteers, it was found that the virtual technologies they use friendly, satisfying, and useful for individuals experience was associated with positive psychological changes among (33). Focusing on the group of patients with obesity and the use of healthy participants, irrespectively of the presence or not of the body VR for their treatment, several studies have studied the acceptability swapping element in their virtual experience (14). of VR platforms for this population (34–39) as well as the efficacy Regarding the BOQ, no differences were found between the two of VR modules as complementary tools to standard face-to-face treatment conditions in the embodiment-related questions. As was Frontiers in Psychiatry 09 frontiersin.org Anastasiadou et al. 10.3389/fpsyt.2023.999656 FIGURE 1 Item scores from Body ownership questionnaire comparing Control and Experimental group, separately distributed in normal weight participants and patients. FIGURE 2 Relationship between body mass index and suitability evaluation questionnaire scores separately distributed in normal weight participants and patients. suggested by Slater and colleagues (14), for the experiment with we compared BOQ differences between groups controlling for sex such conditions to be optimal, strong illusions of body ownership as covariate. are necessary, and ought not to differ between the conditions. This Finally, there was a strong association between BMI and usability seems to have been achieved with our experiments in which results among people from the EG. This result is optimistic as it shows that Frontiers in Psychiatry 10 frontiersin.org Anastasiadou et al. 10.3389/fpsyt.2023.999656 the ConVRSelf platform with both the embodiment and body swapping relaxing, we have incorporated some elements reminiscent of a elements has been satisfactorily adapted to address the specific needs of therapist’s office (i.e., a picture of Sigmund Freud behind the avatar people with higher BMI. Also, this finding is relevant for the future RCT of the virtual counselor). Fifth, to avoid role confusion in the body and justifies our decision to broader the BMI limit of the inclusion criteria swapping experiments, we are planning to add some simple elements to include also patients with “severe” obesity (BMI > 45). to make participants better differentiate their embodiment in each Regarding the qualitative information obtained from the interviews, one of the two virtual perspectives (i.e., deeper counselor’s voice, and almost all participants found the VR experience to be novel, interesting, different items behind each virtual body). Finally, the research team and enjoyable, with higher acceptability among PLWO from the EG than has incorporated a Clean Box1 for disinfection of the Quest 2 device, normal weight participants from the same group. In particular, people which is based on UVC light sanitation. from the EG who engaged in the self-conversation with ConVRSelf The present usability study has provided an important advance achieved a better understanding of their condition and the associated in the development of the SOCRATES project and in particular, the problems, and through the motivational self-conversation, they managed preparation of the RCT. It has shown that the ConVRSelf system is to reflect on the next steps they should follow to achieve their goals. This well-accepted by participants and is now ready to be tested with response from the EG suggests that the MI training had been fruitful and PLWO in a clinical setting. Respectively, through the upcoming RCT that participants were able to learn how to use MI techniques and to with ambulatory patients with obesity recruited from the Vall practice these using the virtual platform to increase their motivation to d’Hebron University Hospital, we expect to demonstrate the enhance with healthy lifestyle habits. effectiveness of the motivational self-conversation in VR using As regards the design of the platform, almost all participants embodiment and body swapping techniques in improving several revealed high satisfaction with the design of the platform, finding it psychological outcomes of these patients, such as several elements attractive, realistic, and relaxing. Most PLWO reported satisfaction related to motivation to change habits (importance, confidence, and with their look-alike avatar while one normal weight participant and readiness) as well as psychological wellbeing. Finally, through the one PLWO criticized the avatar as being unrealistic. integration of MI in the VR context with the patient being properly Some difficulties in using the VR tool were observed, but it is trained to carry out his/her own motivational self-conversation, worth highlighting that most of these issues are easily overcome with we will provide an important advance in the psychological treatments further training of the users on MI and the correct use of the platform, for obesity by addressing some of the root psychological factors and minor adjustments in the platform. No privacy and security issues associated with the problem and promote patient-centered were reported, and neither was any difficulty related to the sex or interventions for this population. educational level of the participants. Regarding the age factor and according to a participant’s statement, for older participants, learning to use these technologies could be harder. Little incidence of simulator Data availability statement sickness was reported, and no further emotional and mental issues occurred during the virtual experiences. The raw data supporting the conclusions of this article will As regards the limitations of the study, first, the sample size was be made available by the authors, without undue reservation. small, something that decreases the statistical power of our findings, and participants were not evenly distributed among groups. Due to this reason, intragroup analyses exploring differences between normal Ethics statement weight participants and PLWO in the dependent variables were not performed, whose results should be additionally controlled for those The current study, which involved human participants, was variables that were found to differ significantly between groups (for reviewed and approved by Drug Research Ethics Committee and instance, age and educational level). Given the intervention delivered Research Projects Committee of the Vall d’Hebron University to the EG, we consider that for theoretical reasons the MI training Hospital. The patients/participants provided their written informed cannot be separated from virtual self-conversation. The differences consent to participate in this study. between groups should be interpreted with caution since the observed effect will always be shared and not reduced to a single factor (MI training or virtual self-conversation). Author contributions Finally, regarding future improvements in the platform to address some of the reported difficulties, first, we are willing to offer patients DA, MS, and PLP conceived the study. DA, JVD, ARQ, AC, MC, and more options to personalize their virtual environments (i.e., by PLP were responsible for the clinical implementation of the study while selecting the counselor’s avatar, including young normal weight, old BS, EAD, and MS adapted the virtual platform to the needs of people with normal weight, young overweight, and old overweight). Second, obesity and offered technical support during the study. The whole team some participants were not satisfied with their look-alike avatar and developed the study design, DA wrote the Introduction, and along with criticized how little resemblance they bore to their real selves. To PGR and PH, they wrote the Methods, the Results, and the Discussion address this limitation, we intend to improve the voices of the avatars sections of the manuscript. All authors contributed to the refinement of and to validate the resemblance of each avatar by a researcher of the the manuscript, reviewed it, and approved its final version. Authorship SOCRATES team, before exposing patients to the virtual experience. eligibility for this publication was determined in accordance with the Thirdly, previous training on the correct use of the platform will be carried out through a video presentation of how to use ConVRSelf. This way, participants will have more tools to be autonomous during the experience. Fourth, to make the virtual environment more 1 https://cleanboxtech.com/ Frontiers in Psychiatry 11 frontiersin.org Anastasiadou et al. 10.3389/fpsyt.2023.999656 European Code of Conduct for Research Integrity (https://allea.org/ Conflict of interest code-of-conduct/#toggle-id-3). MS and BS are Founders of the University spin-off company Virtual Bodyworks. EÁ was employed by Virtual Bodyworks S.L. Funding The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could This study has been funded by the European Union’s be construed as a potential conflict of interest. Horizon 2020 Research and Innovation Programme (grant agreement no 951930). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. This study was also financially supported by the Serra Publisher’s note Húnter program in the form of a grant awarded to DA. All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated Acknowledgment organizations, or those of the publisher, the editors and the reviewers. 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