The usage of virtual avatars in healthcare applications has become widely popular; however, certain critical aspects, such as social distancing and avatar size, remain insufficiently explored. This research investigates user experience and preferences when interacting with a healthcare application utilizing virtual avatars displayed in different sizes. For our study, we had 23 participants interacting with five different avatars (a human-size avatar followed by four smaller avatars in a randomized order) varying in size, projected on a wall in front of them. The avatars were fully integrated with an artificial intelligence chatbot to make them conversational. Users were asked to rate the usability of the system after interacting with each avatar and complete a survey regarding trust and an additional questionnaire on social presence. The results of this study show that avatar size significantly influences the perceived attractiveness and perspicuity, with the medium-sized avatars receiving the highest ratings. Social presence correlated strongly with stimulation and attractiveness, suggesting that an avatar's visual appeal and interactivity influenced user engagement more than its physical size. Additionally, we observed a tendency for gender-specific differences on some of the UEQ+ scales, with male participants tending to prefer human-sized representations, while female participants slightly favored smaller avatars. These findings highlight the importance of avatar design and representation in optimizing user experience and trust in virtual healthcare environments.

翻译：虚拟化身在医疗应用中的使用已变得非常普遍；然而，某些关键方面，如社交距离和化身尺寸，仍未得到充分探索。本研究调查了用户在与使用不同尺寸显示的虚拟化身的医疗应用交互时的体验和偏好。在我们的研究中，23名参与者与五个不同尺寸的化身（一个真人尺寸的化身，随后是四个按随机顺序呈现的较小化身）进行交互，这些化身投影在他们面前的墙上。这些化身完全集成了人工智能聊天机器人，使其具备对话能力。用户在与每个化身交互后被要求评估系统的可用性，并完成一项关于信任的调查以及另一项关于社交临场感的问卷。本研究的结果表明，化身尺寸显著影响感知吸引力和清晰度，中等尺寸的化身获得了最高评分。社交临场感与刺激性和吸引力密切相关，这表明化身的视觉吸引力和交互性对用户参与度的影响大于其物理尺寸。此外，我们观察到在部分UEQ+量表上存在性别差异的趋势，男性参与者倾向于偏好真人尺寸的化身，而女性参与者则略微偏爱较小的化身。这些发现凸显了化身设计和表征在优化虚拟医疗环境中的用户体验和信任方面的重要性。