# A Systematic Review of the Usability of Telemedicine Interface Design for Older Adults
Key challenges associated with current mobile health technologies include the absence of user manuals, unfriendly interfaces, confusing health data visualizations, cognitive overload, and concerns regarding the health record accuracy [18]. The usability of the interface design is closely linked to its design elements. Essential design components of the mobile health interface, such as the layout, images, colors, fonts, language, and buttons, should be convenient, clear, and straightforward to facilitate task completion for elderly users as effectively as possible [12; 19]. Ten usability themes have been identified: satisfaction, ease of use, navigation, simplicity, usefulness, helpfulness, representation, efficiency, errors, excitement, and acceptance [20]. The application's final design, encompassing its features, functionality, information architecture, interactive components, and visual esthetics, was primarily shaped by user-centered design activities grounded in participatory design principles [21]. Based on the MOLD-US framework and design elements, this study categorizes four groups of factors: the functional framework, interaction logic, visual design, and user experience. The functional framework mainly refers to information architecture, which streamlines information retrieval and task completion, ensuring intuitive navigation for actions like accessing specific blood test results [21]. Interaction design focuses on input-output methods, status displays, and feedback mechanisms, covering both local and global responses [22]. Visual design emphasizes the interface's perceptual attributes, including visual, auditory, and tactile characteristics, and follows basic visual language principles such as hierarchy, spacing, alignment, and color usage [22; 23]. User experience encompasses the full emotional, cognitive, and behavioral responses that occur before, during, and after interacting with a product, aiming to ensure the device is user-friendly, comfortable, visually appealing, and capable of fostering sustained user engagement [16; 24]. Over the past decade, numerous systematic reviews on telemedicine for the elderly have concentrated on summarizing mobile applications for specific diseases rather than addressing telemedicine interface design or usability. These reviews encompass studies on the usability in pain management [25], health outcomes for cognitively impaired patients [26], mobile technology for spinal disorders [27], telemedicine monitoring for head and neck cancer [28], improving medication adherence in patients with affective disorders [29], and examining the mental health of older adults to help reduce social isolation among them [30]. Many review articles also examine telemedicine for the elderly through the perspective of influencing factors, utilizing the Technology Acceptance Model (TAM) and Unified Theory of Acceptance and Use of Technology (UTAUT) to analyze acceptance and its determinants [31; 32; 33; 34], but these studies did not link the influencing factors into interface design recommendations or strategies. The Technology Acceptance Model (TAM) is proposed by [PERSON] for understanding receiving information and technology systems [35]. It has three key factors: perception, behavior intention and actual system use. The perceived usefulness (the belief that a system enhances the performance) and perceived ease of use (the belief that minimal effort is required) are key factors in technology acceptance [36; 37]. Patients perceive telemedicine as beneficial only if it improves the service speed, reduces examination costs, optimizes records, and shortens the consultation time [38], all of which are closely related to interface design. On the contrary, when patients experience worry and fear while using telemedicine, it can hinder the use of telemedicine [37]. The causes of such concerns may include system complexity, unreasonable interaction, and poor experience.