Mobile applications on smartphones and tablets have become part of our everyday lives. The number of augmented reality (AR) technology applications is also increasing. Augmented reality has proven to be effective in various areas of human life, from education, marketing, and training to navigation. All people have the right to access information and use available technologies, but not everyone has the same opportunities. To contribute to the digital inclusion of people who are often disadvantaged in this regard, we should think about the accessibility of digital technologies, including mobile augmented reality (MAR). The specificity of MAR is a new way of human–computer interaction compared to traditional mobile solutions. The objective of this review paper is to analyze the handheld AR solutions developed for people with different disabilities to identify accessibility challenges related to interaction when performing different tasks in AR. It also explores and presents accessibility features and other accessibility best practices, as well as potential future research directions related to the personalization and customization of such solutions for individuals. The results of this literature review can contribute to the creation of accessibility guidelines in the field of handheld AR and encourage the development of accessible AR solutions that can benefit not only people with disabilities but also people without disabilities. Today, technological progress is taking place at an exponential rate, allowing technologies to move more rapidly from research laboratories to the marketplace. New ideas and products are accepted by new customers faster than before. Computers, smartphones, the internet, and social media are examples of the technologies in use today with rapidly increasing adoption rates. The exponential progress of enabling technologies in terms of computing power, big data, device connectivity, and internet performance, has enabled the development of solutions based on emerging technologies that are robust enough to be valuable to consumers and useful to the public. To develop a mainstream solution that fulfils its role, the user-centered approach needs to be followed; otherwise, there is a risk of having to re-engineer a solution because it does not reflect the specific needs of a certain group of people, e.g., people with disabilities . When taAccording to studies described in , the majVR is most known for its major use in gaming as it allows gamers to have a full-immersive experience in the gaming world. Having in mind ubiquitous computing and that people are naturally more directed towards the real world instead of virtual, AR excels as a more appropriate technology since it provides a simple and immediate user interface to an electronically enhanced physical world . The mosDespite ongoing challenges, AR holds the potential of being used in many different fields. Apart from applications for specific domains, such as industry and construction, maintenance and training, or medicine, AR can be used by a broader audience in use cases that involve everyday tasks, such as finding information about places of interest in their surroundings, navigation and support while following a route, augmentations in advertising and commerce, helping consumers make buying decisions, and support while learning, as well as AR gaming, which is expected to be the consumer use case with the most investment in 2024, together with VR gaming and VR video/feature viewing . Most ofConsidering the benefits that AR can bring as a new way of human–computer interaction in the real world and the fact that AR applications are becoming ubiquitous and part of our everyday life, the question that imposes itself is: “Will everyone be able to experience engagements with augmented reality?”. To take full advantage of the benefits that advancements in the AR domain can bring to the world, one needs to think about the accessibility of different products and services that are being developed, i.e., whether all users be able to use them regardless of their capabilities and limitations. In addition, to achieve full accessibility, compatibility with assistive technologies needs to be assured. For example, a screen reader is an assistive technology whose compatibility with devices, such as smartphones and computers, is imperative for visually impaired persons to perceive information that appears on the websites or different applications running on the devices. Since there are over one billion people worldwide living with some form of disability , the accIn this paper, a systematic literature review (SLR) of existing handheld AR solutions for people with disabilities is performed. This SLR allows us to obtain an overview of AR solutions developed for people with disabilities in terms of interaction tasks and techniques required by users with different disabilities, to identify accessibility challenges that need to be addressed in future work. Thus, the focus is not on describing the functionalities of solutions, but rather on exploring different interaction techniques required to perform AR tasks, with an emphasis on multimodality and alternative ways of interacting with virtual objects. This is very important because only if appropriate input and output modalities are found for each person can the full potential of AR-based solutions be realized. Although AR is mostly associated with visual augmentations, other sensory modalities can also play an important role. For example, tactile technologies can now enable interfaces that can be invaluable for people with different disabilities. For people with motor difficulties participating in home-based telerehabilitation, providing tactile feedback can be useful to improve motor control performance and learning , while fRQ1: What types of handheld AR solutions are being developed for people with disabilities?RQ2: What common interaction tasks are required in handheld AR solutions for people with disabilities?RQ3: What interaction techniques are being used for performing common tasks in handheld AR solutions for people with disabilities?RQ4: What accessibility features have been implemented in handheld AR solutions for people with disabilities?RQ5: What research methods were applied in the design of handheld AR solutions for people with disabilities?The focus in this review is put on handheld displays, i.e., on the techniques developed for touch screens that involve 2D gestures and (multi)touch, but other input modalities such as voice command and device-based interaction are also considered. Although AR can augment the real world not only visually, but also with sound, touch (haptics), smell, and taste , in this paper the focus is on handheld displays integrating mostly visual modality . One can think that in this way people with visual impairments are excluded, but visual AR can be made accessible to them as well if the support for assistive technologies is implemented. With respect to the goal of this paper, the following research questions (RQ) are defined:This paper is organized as follows. Accessibility is defined as a measure that indicates how much some product, service, or environment is suitable for all users, including people with disabilities as well as elderly people. Since several types of disabilities can be distinguished  where one person may have more than one disability, it is not always easy to meet all the needs of people with disabilities. Although they are a heterogeneous group of users and their requirements are often contradictory, we need to strive towards the fulfilment of as many requirements as possible. The key approach to achieving accessibility is User-Centered Design (UCD) which is based on the active involvement of users to improve the understanding of user and task requirements, and the iteration of design and evaluation . BesidesThe importance of digital accessibility is recognized worldwide as there are many legislation and public policies that obligate public sector bodies to make their websites and mobile applications accessible ,19. TherImportant guidance can be found in the domain of extended reality (XR). XR is an umbrella term for VR, AR, MR, and all future immersive technologies that can merge the physical and virtual worlds . XR AcceSince AR is a rapidly evolving field and many users often find themselves experiencing AR for the first time, it is important to develop products that are intuitive and include well-explained instructions or illustrations. There are examples of demonstration applications and design guidelines for developers that cover different AR principles and patterns, such as ,26,27, bTo be able to offer such guidelines that will consider all the factors affecting accessibility, extensive research needs to be performed in this field. Although the emergence of AR impacted the growth of research in AR in general as well as in the accessibility domain, the interest in AR for people with disabilities remained relatively low. According to , researcTo contribute to the essence of the AR accessibility problem, it is necessary to fully understand the needs of users with disabilities regarding interaction techniques in AR and the appearance of virtual objects in the real environment as this is the main difference between AR applications and usual mobile applications that already have established interaction mechanisms. This systematic literature review (SRL) contributes to a better understanding of the interaction-design principles for people with disabilities in handheld AR solutions by providing an analysis of research studies and papers describing AR solutions for people with disabilities, focusing on the different interaction techniques required in AR. The results of this SRL may also contribute to the creation of accessibility guidelines in the field of handheld AR and encourage the development of accessible AR solutions. Further research and development in this area motivated by this paper will also have an impact on expanding the field of digital inclusion. The following sections describe the systematic process of the literature review and the results relevant to the field of accessibility of AR for handheld devices.A systematic literature review (SLR) in the field of accessibility for handheld AR solutions is conducted following the PRISMA method . The oveIdentification phase, whose goal is to identify the number of papers according to the defined search strategy. Our search strategy includes searching the Web of Science Core Collection database, which is a trusted, high-quality collection of journals, books, and conference proceedings available on the Web of Science multidisciplinary platform with more than 74.8 million records [A equals to  in the title (TI);B equals to  AND (“mobile” OR “handheld”) AND  in the abstract (AB);C equals to  AND  in the author’s keywords (AK).The first review phase is the  records . The seaThe database search results were concluded in January 2022, considering publications written in English as well as publications published between 2010 and 2022. Additionally, document types included in the performed search are proceedings papers, articles, and early access papers. The initial database search retrieved 109 publications. An additional seven records relevant to the topic were identified through other sources , and thus were included from the beginning of the process. Screening phase in which the publications were reviewed by title and abstract. The main inclusion criterion in this phase was: the publication presents a solution that is based on handheld AR and is related to people with disabilities in terms of inclusion , development for specific disability (assistive tool), or universal access in general . Publications were excluded in accordance with the following exclusion criteria: (i) accessibility is mentioned in the context not related to people with disabilities, i.e., the term is used in the context of affordability by price or access to information; (ii) the solution described in the publication is not related to handheld AR but rather to spatial AR or head worn AR, i.e., smart glasses or HMD, or it uses additional sensors like Kinect for recognizing hand gestures; (iii) AR solution is considered from the perspective that is not related to people with disabilities, e.g., in connection with network latency, machine learning, cloud computing, cultural heritage, medical education; (iv) the solution described is VR- or MR-based, not AR ; (v) there is no concrete solution mentioned or any AR details; (vi) AR is not the main technology used or the main functionality of the solution/system, e.g., the publication is more related to robotics or BCI (brain–computer interface) research. If reviewing the title and the abstract did not give enough information to decide whether the publication is relevant for the review, that publication was included in the full-text eligibility assessment. In this phase, 50 publications from the search track were excluded.The second phase of the systematic review is the Eligibility phase. A total number of 66 publications were included in the full-text assessment for eligibility. The exclusion criteria in this phase were the following: (i) the solution presented in the publication is not based on handheld AR (when this was not obvious from the title and abstract); (ii) there is no description of an AR application or details related to interaction technique(s) used, e.g., the publication only provides examples of situations/use cases in which the AR application can be used; (iii) the description of an AR solution provides guidelines on how it can serve as an authoring tool for educational content, and not how it can be used by people/students with disabilities; (iv) the AR application is described in its early stage of development or planning. After full-text reading, some publications were identified as connected research or continuations of a study, where, e.g., the older publication is a conference paper, and the other one is a journal article on the same topic. Thus, in that case, only journal article was considered and included in the analysis.The third phase of the process for selecting publications to be included in a systematic review is the Included publications for the SLR that include seven additional publications included from the beginning of the process that remained eligible to the end of this phase. An overview of publications selected for the SLR, as well as the results of their analysis, is provided in the next section.In the last phase, we concluded the number of 32 At the beginning of the analysis, publications were categorized by the year of publication and publication type. Although the literature search performed considered publications from 2010 onwards, among the papers included in the analysis there were no papers from the period from 2010 to 2014. Since 2015, the number of papers relevant to the topic of AR accessibility is between 4 and 6 through the years, with a slightly higher number of conference papers (62.5%) compared to journal articles (37.5%). Given this fact, we can say that the importance of this research topic has attracted the attention of the research community since 2015, which is not surprising because only then did handheld AR become more popular and affordable among the general public. The distribution of papers by year and type of publication can be seen in In the next sections, we bring results based on the literature review of publications included which provide answers to the research questions defined. Each publication is read thoroughly, and data were extracted into a Microsoft Excel spreadsheet for analysis, covering aspects of the following areas: (1) AR characteristics used in solutions developed for people with disabilities ; (2) Common interaction tasks required in AR handheld solutions for people with disabilities; (3) Interaction techniques used for performing common tasks in AR solutions for people with disabilities; (4) Accessibility features identified in AR solutions developed for people with disabilities ; (5) Research methods applied in the design and evaluation of handheld AR solutions for people with disabilities.In this section, we classify AR solutions described in publications by characteristics specific to AR mobile tracking systems. Tracking refers to the registration  of a virtual object in the real world and continuous tracking (measurement) of the viewer’s position and orientation in relation to some “anchor” in the real world . DependiThe analysis of the publications by the tracking technology type used in the AR solution shows that the largest number of solutions is based on vision-based technology (about 78% of solutions). Three solutions are based on location-based tracking technology (about 9.5%) and the rest of the solutions fall into the category of hybrid solutions (12.5%). Out of vision-based solutions, only five of them (20%) use the markerless type of technology, i.e., they use the environment or real-life objects as tracking targets, while the rest of them (80%) use marker-based technology. Most of the triggers for the marker-based solutions are visual markers or images related to study material , while other visual markers are based on the QR code format, with images of objects prepared in advance so that they can be recognized, and one solution with AR markers on a tangible object (AR cube). All the location-based solutions use a GPS signal as a primary tracking technology and all the applications serve as an assistive tool for wayfinding and improving navigation skills. Regarding hybrid tracking technologies used in a certain solution, most of them are related to tracking the GPS signal in combination with inertial tracking, e.g., tracking the device’s orientation and direction of pointing, but also a combination of GPS signal with pattern recognition is used. There are no solutions that are based solely on inertial tracking technologies because inertial tracking targets are typically used in combination with other primarily used tracking techniques to improve recognition and tracking accuracy.Cognitive, learning, and neurological disabilities (CLN), i.e., 18 solutions or about 56%, which is understandable because this category includes the most diverse group of users compared to other types of disabilities. Solutions for people with attention deficit hyperactivity disorder (ADHD), autism spectrum disorder (ASD), intellectual disabilities , mental health disabilities, perceptual disabilities , and cognitive impairments  are included in this category. The Multiple disabilities category refers to solutions that are not strictly defined for a particular disability but can be used in different cases and are thus designed, e.g., solutions are intended for children with special needs who require a different type of support, or the elderly with various impairments . There are four such solutions, and the same number of solutions, or 12.5%, have been found for the categories of Physical and Visual disabilities. The least number of solutions (only two) have been found in the category of Auditory disabilities. In almost all categories of disabilities , solutions based on visual tracking technology prevail, especially marker-based solutions. For auditory disabilities, marker-based solutions are the only ones found, while for physical and multiple disabilities there is one markerless solution in addition to marker-based solutions. In the CLN category three solutions based on GPS signal can be found, two markerless solutions and one hybrid solution. In the category of visual disabilities, there are three hybrid solutions and one markerless solution, i.e., no marker-based solutions, which is also understandable because, to augment the real world, you need to point a device towards a marker or other trigger which is difficult for the blind and low-visioned people.The distribution of AR handheld solutions based on a certain tracking technology type categorized by disability types for which the solution is developed can be seen on the graph shown in Given the application domain for which a solution was developed, most of the solutions belong to the educational application category (about 53%), with most being for the CLN category, while solutions for the visual impairment category were not found. The next application category by a number of solutions represented (about 19%) is navigation (or wayfinding assistance), for which no solutions for auditory disabilities were found. The same number of solutions (12.5%) can be found for the application areas of rehabilitation and assistive tools. Again, there are no solutions for auditory disabilities, and there are no solutions for visual impairments in the rehabilitation area. Only one solution (3%) belongs to the category of training application domain category for multiple disabilities, i.e., for elderly people who may have different cognitive and physical abilities. The graph representing a described distribution of AR solutions by type of disability, categorized by area of application, can be seen in Most solutions use visual output as the primary modality with accompanying audio or voice reproductions. Types of virtual visual content used in AR solutions are various, from 3D objects, images, animations, shapes, videos, and text, to on-screen information, and most are independent of the tracking technology type, except for GPS-based solutions in the navigation domain, where on-screen information, such as different 2D graphics, text, or symbols indicating the right path and information about location and distance are used as augmentations. In educational applications, different combinations of AR content are used regardless of the tracking technology type. Furthermore, 2D and 3D graphics are mostly used in rehabilitation applications, while assistive tool augmentations depend on the disability category. For example, assistive tools for visually impaired and blind people combine 3D objects and audio, where the audio output is the primary modality, while for dyslexic people the augmentation is an alternative display of text and background. The only solution in the training domain uses additional information to instruct workers during operation. Information Browser—an interface for showing AR information in the real world; 3D User Interface (UI)—uses 3D interaction techniques to manipulate content in space (through controllers); Tangible UI—uses real objects to interact with AR virtual content; Natural UI—uses natural body input such as freehand gestures; Multimodal UI—uses combined speech and gesture input [Regarding the way the user interacts with the virtual content in an AR application, we can distinguish the following AR interface types: re input . Almost re input . SolutioObserving Virtual Content category are identified in every AR solution , they are not considered in the table. In general, all AR solutions include some type of task from Establishing Physical/Virtual Correspondence category since this is necessary to create a relationship between the real-world and virtual content appearing on the screen. The biggest percentage of solutions from this category (62.5%) belongs to the Scan marker task type which is in correspondence with the fact that most of the AR solutions analyzed are based on markers. In this task category, the same percentage of solutions (15.6%) include Scan location and Scan environment tasks, while 12.5% of solutions include Scan object tasks. None of the solutions from CLN and auditory disabilities categories use scanning of the environment as one of the constituent tasks. Additionally, Scan location is used only in solutions from categories of CLN and visual disabilities while Scan object is used only in solutions for CLN and physical disabilities. The second most popular task type is the Trigger effect from the Activating Virtual Content category of tasks; 21.9% of solutions include this task. This task type includes actions such as triggering sound effects, animations, and additional content (text or sound information). In this task category, there is also the Select type of task which is included in 15.6% of solutions, most of them in the visual disabilities category and related to the selection of a certain location. From the Transforming Virtual Content category, the most popular task types are Move and Rotate, since 12.5% of solutions include this task type while 9.4% of solutions include the Scale task and only one solution includes the Color transformation task. The Place object type of task from the Placing Virtual Content task category is included in 12.5% of solutions, and it is not specifically related to any of the disability categories.When talking about accessible alternatives for interactions in handheld AR, it is important to distinguish the types of interactions required by the users for performing constituent tasks in mobile AR applications. By using an existing taxonomy of constituent tasks (from ), differIn this section, we bring interaction techniques identified for AR interaction tasks together with the description of the input method (procedure) required to perform the task. As mentioned before, the emphasis in this paper is put on handheld AR, which means that the device on which the AR solution is being used is either a smartphone or tablet. An AR solution that uses a laptop with a webcam is also considered if the same interactions can be applied to handheld devices. Most of the solutions considered in this review are used on handheld devices, so it is understood that a user needs to hold the device with one or both hands. This is emphasized later in the description of the input method if the procedure, besides holding a device, includes a precise pointing from a user to, e.g., scan a marker, image, or specific location, or if the environment around the user needs to be recognized or established to continue using the application. Two solutions are exceptions where the user does not interact with the device but brings the markers or tangibles in front of the device camera, while the device is positioned on the stand, or a device is a laptop with a webcam. Most of the interaction techniques are common for mainstream AR solutions, except for specially designed interactions for visually impaired users, i.e., screen-reader users, as is the case in . The resEstablishing Physical/Virtual Correspondence category have a similar goal and thus interaction techniques for accomplishing them are similar (Point(ing) to…), but again their input methods differ depending on the application domain, as can be seen from the table. In some solutions, it is enough to find a surface where an object will be automatically placed , tap, or pinch to zoom, as well as with UI interactions, such as a slider or button.Interaction techniques identified in AR solutions are summarized in  placed , while  placed . The caPlacing and Activating Virtual Content, different interaction techniques for screen reader users are identified depending on the application domain (retail or education) [Manipulating virtual objects can be a very complex task (considering that at the same time a user needs to hold a device), so the way of performing an interaction can play a big role in the accessibility of a solution. Only a few solutions provide alternative interaction techniques or input modalities for virtual object manipulation. One solution provides different types of UI elements for performing the same actions , while tucation) .Click and Tap is similar, the difference between them is the target on the screen with which a user interacts. When a target is static on the screen, such as the UI button or other virtual content that appears after activation, the user clicks on it, while for targets that are anchored in the real world, the user must hold the device in a certain direction to have the target in the camera view and then tap on the screen where the target is visible. These interaction techniques occur in both AR task categories: Transforming and Activating Virtual Content.Although the input method for the interaction techniques Other interaction techniques mostly depend on the certain application domain and are designed so that they address certain needs, e.g., in the solution for the rehabilitation domain , to perfPerceivable, Operable, Understandable, and Robust) as they are highly relevant to both web and non-web mobile content and applications [multi-modality is one of the requirements emphasized in the XAUR document as one of the ways for fulfilling diverse user needs related to accessibility in XR [Given that AR solutions included in this review are developed for people with disabilities, the solutions are accessible at least to the target group of users. Thus, we extracted accessibility features that can be considered good practices for addressing AR accessibility challenges when developing handheld AR solutions for everyone. Accessibility features shown in ications . In the ty in XR . AdditioPerceivable group address the user needs related to making AR content and UI elements presentable to users in ways they can perceive them. Providing more than one input or output modality allows users to perceive the content in the form they need, e.g., by providing text alternatives for any non-text content. In addition, if there is an option to adjust the content by changing the color, contrast, font type and size, or by providing an alternative screen display, users will have a more accessible representation of all the information they need to make the best use of the application. In the Operable group, there are accessibility features related to UI elements and navigation through screens that allow the user to perform the required interaction. For example, in some solutions, an audio interface works alongside the visual interface, enabling hands-free interaction if speech recognition is implemented. This group also includes UI elements with features that are necessary for some users to interact more easily, such as larger buttons or buttons with large interactive touch zones, alternative elements in case it is difficult to use the default ones, or additional features such as the Freeze feature. The accessibility features in the Understandable group refer to making information and the operation of UI comprehensible to different user groups. To make content more understandable, some might request more simplified text, while others might appreciate easily recognizable icons for buttons or animations to explain tasks. A general design guideline for the UI would be that it is intuitive and consistent, and this is no exception in AR solutions. The accessibility features that belong to the Robust group are any that meet the requirement that the content can be interpreted by a variety of user agents, including assistive technologies, which is the case for all solutions supporting screen readers, so they are not listed in the table. Publications that are not listed in the table and from which accessibility features have not been extracted mostly refer to AR solutions that use the Aurasma application, which is an authoring tool  and it is not possible to add features other than scanning the marker, or AR navigation applications .The accessibility features in the Qualitative, Quantitative, and Mixed. In the table, the column entitled Data collection refers to the techniques in the phases of requirement collection or solution evaluation to collect data. About 90.6% of the systematic literature review publications indicated which methods and/or techniques they used in the research design or evaluation of the AR solution. The definitions for qualitative and quantitative methods were taken from [In this section, we present a summary of methods used in the research, design, or evaluation of handheld AR solutions for people with disabilities. In addition to presenting methods and techniques used in the research and design of evaluated solutions, we also mention what data were collected to confirm the usability of these solutions . ken from . The perIn terms of metrics collected during application testing, researchers in  measuredFuture evaluations in similar research could be based on artificial intelligence, as is the case in , which dThe accessibility features described in Guided Access) for iOS devices that allows disabling the Home button and touch functionality of some parts of the screen. This can be helpful to pupils with autism, attention disorder, and mental disabilities to better concentrate on the task.Authors in  emphasizIn the study described in , researcAnalysis of the evaluation results for the next AR solutions derived some useful findings that can be taken into consideration in the development of new solutions. For example, evaluation results in  showed tSome relevant findings regarding design concepts for learning environments can be found in , as the One of the findings in  for enhaIn the study described in , there wIn an empirical study described in , older pWhen designing interaction techniques so that people in wheelchairs can use the application, it is necessary to consider the position of markers if the application is marker-based . AdditioverTHERE, described in [Research on image-enhancement applications for people with low vision has investigated various image transformations, including contrast enhancement, color transformation, intensity-edge enhancement, and magnification and image stabilization, as mentioned in . Assistiribed in . A more ribed in , where tAn application described in  is intenOne of the rare AR solutions that has implemented accessibility options is the one described in . AccessiAll of the above findings are a good start for further research in the field of inclusive AR applications, as there are no concrete guidelines on how to apply them to AR content or new interactions required in AR applications. As this review has shown, there are attempts to make content and interactions more accessible in applications developed for specific audiences. However, there is a lack of concrete steps for developers and designers to develop AR applications accessible to everyone.This systematic literature review is conducted with the goal of answering five research questions. At the beginning of the discussion, the results of a bibliometric analysis are commented on. It should be noted that no publications with relevant information for the field of accessibility in mobile augmented reality (MAR) solutions were found before 2015. The average number of 4.5 publications per year since then indicates that awareness should be raised for the development of accessible MAR solutions for all. Publications in this review were considered based on their relevance to the field of accessibility, i.e., if they included a description of the solution used in the study with interaction techniques and/or features relevant to improving the accessibility of the solutions. Since these solutions were developed exclusively for people with a specific type of disability (or multiple disabilities), interaction techniques and additional features are examined in more detail, as they can be considered important if users were satisfied and rated them as usable/accessible.The most popular type of mobile AR solution for people with disabilities in the last decade is marker-based solutions, which use markers (different types of triggers) for establishing correspondence between the physical and virtual worlds. As with most solutions used in education, the majority of triggers for marker-based solutions are located in a textbook or electronic book, on flashcards or learning objects, or in the form of images associated with the learning material or other visual markers. The next-most popular type is location-based solutions used to support navigation or wayfinding. The primary trigger signal here is GPS, and this is also true for hybrid solutions that use inertial tracking triggers in combination. Very few solutions are based on markerless tracking, although this is a more flexible form of AR than the marker-based method. Considering that this technology is at present developed to improve the experience of AR and that it allows object occlusion, better immersion, and novel interactions, this tracking type should be better explored in terms of use by people with disabilities.Considering that cognitive, learning, and neurological (CLN) disabilities can affect the ability to move, hear, speak, and understand information, this category includes the most diverse group of users, and most solutions are found for this category of disabilities. Solutions for visual impairments are found only in the navigation and assistive tool categories, meaning they are underrepresented in other application areas. In general, the technologies used for game development still do not provide adequate support for assistive technologies such as screen readers, and accessibility-aware developers must rely on their efforts to do something about it. Another complicating circumstance is that there are no guidelines or standards for how AR content can be made visible to assistive technologies. Therefore, additional efforts should be made to explore this area so that people with visual impairments can use applications in a variety of settings. The category for which the fewest solutions have been developed, and which therefore has the greatest potential for further research, is auditory disabilities. The reason for this could be that people who are deaf or hard of hearing can perceive information primarily visually, and many applications contain instructions only in text form. Content in text form is not useful especially for people who are deaf from birth, as they often cannot read. In this case, a highly simplified text, illustrations, or sign language can be helpful for them, which is difficult to implement in such a solution, especially considering that each country has its sign language or the content changes dynamically.Most augmentations in analyzed solutions are visual, and range from on-screen information in the form of 2D graphics, text, and icons that appear on the screen  to various images, animations, videos, and 3D objects. While 3D models representing different objects from the real or virtual world are expected to provide more opportunities for interaction, other types should not be neglected. All augmentation types should take into account different aspects of accessibility, such as applying different accessibility options depending on the user’s needs . This is especially important for educational applications where different AR content is used as a means of learning school subjects, or for navigation applications where it is important to find the right path in an unfamiliar environment.Given that almost all of the handheld AR solutions for people with disabilities studied use an AR information-browser type of interface, further research efforts can be made to investigate the potential of other types of interfaces for people with disabilities, whether it is a primary interface or an alternative interface for users with disabilities. When looking at the tasks identified in each solution, it is interesting to note that for the most numerous solution category by disability (CLN), no tasks were found for scanning the environment, transforming virtual content in the form of scaling and color change, and the task of selection. Similarly, the solutions for people with physical disabilities did not include any tasks for scanning the location and placing a virtual object. Additionally, the solutions for people with visual impairments did not require the user to scan the markers or the object or transform the object in any way. All of this suggests that further efforts are needed to include people with different disabilities in the development of solutions so that they comply with the principles of universal design and allow equal use of all solutions without restrictions on certain tasks that “they cannot do” or can do if there are alternative ways to do them.Pointing to interaction technique, which requires the user to hold the device with one or both hands and point the device’s camera, usually located on the back of the device, at the target if a marker-based technique is used, or at the environment to establish physical–virtual correspondence if a markerless technique is used. Depending on the application, the device can be used in portrait or landscape orientation. Considering that some people have motoric difficulties, whether they have limited movement or can only use one hand, it would be beneficial for their inclusion and sense of equal participation regarding their limitations to find a way to perform this type of AR task. It is challenging for people with visual difficulties to determine their exact location when they do not know what is in their immediate and wider surroundings. One of the guidelines for their inclusion would be to provide them with audio descriptions of their surroundings and guide them on what to do. For people with cognitive or learning disabilities, one guideline would be to include simple animations that show them exactly what to do to establish a physical and virtual correspondence so they can continue to use the application. Just these few examples show that it would be beneficial to have alternative ways to use the application that meet different user needs. This can be enabled by providing appropriate accessibility features in the application settings or by including them in the design of the application during implementation.In AR applications, different types of interactions may be required of the user to perform certain AR tasks, such as scanning a marker, object, or environment; placing, moving, or rotating an object; or triggering certain effects. Depending on the type of application and the disability for which a solution is developed, different interaction techniques are used for specific AR tasks. Since tasks involving scanning are the most common, it is worth looking at the interaction methods required for this interaction task. Most scanning tasks involve the User needs may depend not only on the type of disability but also on the age of the user. While it is important for most AR solutions for children to provide multiple means of representation, especially for solutions intended for learning, for solutions intended for adults it is important to ensure support for assistive technologies such as screen readers or to provide alternative input methods such as voice commands. While older users may appreciate large game buttons, it would be beneficial for all age groups to provide accessibility options to change the appearance of content from UI and AR in terms of color (contrast), font type, and size, as well as to provide clear instructions. Many different requirements need to be considered to meet different user needs. This is a very complex task, as these requirements can be contradictory, even if they are found in the same age or disability category. This is also mentioned in  for peopIn , a case The motivation for the proposed future work is described in this section. The authors of the review article , which pAccessibility is an important aspect of achieving social and digital inclusion. While mobile augmented reality has already entered our lives, not enough attention has been paid from the beginning to how AR solutions can be made accessible. This paper aims to provide a review of handheld AR solutions developed for people with disabilities between 2010 and 2022 that are relevant to the field of accessibility. The results of this review help us understand what interaction tasks and techniques in handheld AR solutions are required from users with different disabilities to find research gaps in terms of accessibility that need to be addressed in future work. The accessibility features of each solution are explored and extracted together with other accessibility good practices. Certain accessibility features can be beneficial to all users, e.g., voice commands that enable users with different disabilities to manipulate the augmentations will also allow hands-free operation for all users.Considering the very heterogeneous needs of users with permanent or temporary disabilities, it is a very complex task to develop a solution that fulfils all their, usually conflicting, needs. Besides having in mind the accessible design of the solution, for AR solutions on mobile devices, one must think about accessible interaction techniques, which is not a clear-cut decision, since different users may prefer different interaction types. To know which user group prefers which interactions in the context of accessibility, tracking objective and subjective measures while a user uses the application imposes itself as a possible solution. Besides the input method required to perform a certain task in the AR solution, different contextual factors can affect the usability and accessibility of an AR solution, such as different environmental factors  as well as the size of the device  or internet access. All of these must be considered when defining accessible interaction techniques and content display for a certain user.By employing some simple principles that apply to website accessibility, developers can make AR solutions more accessible to people with disabilities. Making AR solutions accessible to as many users as possible requires more thought about accessible interaction options. By allowing alternative options for interacting and viewing content, we are getting closer to a solution that is designed around the principle of universal design, which is the goal for all solutions that people use every day. The results of this literature review will aim at formulating guidelines that will enable developers and designers to seamlessly achieve the ultimate goal we should all strive for, which is the social inclusion of children and people with disabilities, as well as the elderly, using emerging technologies that have already proven useful in a variety of settings.


This study aims to examine the effects of early rehabilitation on functional outcomes in patients with acute ischemic stroke treated with endovascular treatment (EVT).Eligible patients with large vessel occlusion stroke treated with EVT, who received early rehabilitation or standard care treatment during hospitalization, were enrolled in a multicenter registration, prospective observational study, a registration study for Critical Care of Acute Ischemic Stroke After Recanalization. Early rehabilitation was defined as rehabilitation interventions initiated within 1 week after acute stroke. The primary outcome was the favorable functional outcome  at 90 days. Independent association between early rehabilitation and the primary outcome was investigated using multivariable logistic regression in the entire sample and in subgroups.p = 0.41). Patients in the early rehabilitation group had a lower death rate within 90 days compared with the standard care group . The multivariable logistic regression analyses showed that the early rehabilitation was not significantly associated with the favorable functional outcome at 90 days . There was no significant difference between subgroups in the favorable functional outcome at 90 days. No significant interaction was found between subgroups.A total of 1,126 patients (enrolled from July 2018 to May 2019) were included in the analyses, 273 (24.2%) in the early rehabilitation group and 853 (75.8%) in the standard care group. There was no significant difference in favorable functional outcomes at 90 days between the two groups (45.4 vs. 42.6%, Patients with stroke receiving early rehabilitation had a lower death rate. However, these clinically meaningful effects of early rehabilitation did not show on functional outcome at 90 days in patients with large vessel occlusion stroke treated with EVT.http://www.chictr.org.cn; Unique identifier: ChiCTR1900022154.URL:  Stroke is the leading cause of long-term disability in developed countries and one of the top causes of death worldwide . EndovasGuidelines have recommended early mobilization after stroke to improve activities of daily living , 5–7. DaThis study examined the effect of early rehabilitation on long-term functional outcomes in patients with LVO stroke after EVT, using the database of a national clinical research center for neurological diseases in China.The database was developed by a registration study for Critical Care of Acute Ischemic Stroke After Recanalization (RESCUE-RE). RESCUE-RE is a multicenter, prospective observational study that has been completed. The clinical database was developed based on data from 18 comprehensive stroke centers across China. The aim of RESCUE-RE was to evaluate the short- and long-term outcomes of patients with AIS who received EVT in the real-world clinical practice.http://ctms.tt.zhinanmed.com. Baseline clinical information and outcomes were collected by trained research coordinators. Compilation of completed forms from all centers was examined by full-time study-quality coordinators.In RESCUE-RE, data from individual patients were systematically collected in each center and clinical databases were collected through China National Clinical Research Center for Neurological Diseases at (2).In this real-world clinical practice study, the clinical data of patients during the period between July 2018 and May 2019 were collected from the China National Clinical Research Center for Neurological Diseases. All patients met the following criteria: (1) age>18 years, (2) AIS confirmed by cerebral imaging, and (3) treatment with recanalization for AIS according to the current guidelines , vagal reaction (bradycardia or nausea), a >40 mmHg increase of blood pressure topping 180/100 mmHg, or a symptomatic decrease in blood pressure, would be put back in bed  mobilization, correct positioning in bed, sitting balance activities, facilitation of limb and trunk control activities, and education of patient and caregiver. Both groups received standard care treatment, for 45 min a day, for 14 days, or until discharge .The patient characteristics were prospectively collected in all participating centers. Successful recanalization was defined as a thrombolysis in cerebral infarction (TICI) score of 2b or 3 after EVT , 19. Sec2 tests or Fisher's exact test for dichotomous variables and Student's t-tests or Mann–Whitney U test for continuous variables. The level of significant difference was set at p < 0.05. Multivariate logistic regression analyses were performed to evaluate the relationship between favorable functional recovery (mRS 0–2) and the implementation of rehabilitation. These independent variables were chosen based on their clinical significance, previous studies (p < 0.05). Model 1 was adjusted for age, sex, diabetes mellitus, hypertension, atrial fibrillation, dyslipidemia, smoking, education, and insurance. In model 2, time from stroke onset to admission interval, mRS before the stroke, baseline NIHSS score, NIHSS score at 24 h after EVT, the side of the brain where the stroke occurred, and stroke cause were added. In model 3, successful recanalization, defined as a TICI score of 2b or 3, was further added. Subgroup analyses were performed to detect heterogeneity in rehabilitation's effects on the primary outcome with statistical tests of interactions. All statistical analyses were performed using SAS software v 9.4 .The demographic and clinical characteristics were compared between the early rehabilitation group and the standard care group using χ studies , 21, 22 The study protocol was evaluated and approved by the medical ethics committee, number KY2014-045-03. All patients provided written informed consent to participate in the study. This trial was registered with the Chinese Clinical Trial Registry, number ChiCTR1900022154.A total of 1,218 patients with AIS treated with EVT were enrolled in RESCUE-RE. Among them, 34 patients without rehabilitation therapy data, 31 patients with a prestroke mRS of > 2, and 29 patients lost to follow-up at 90 days were excluded. Data on 1,126 patients were analyzed, 273 (24.2%) in the early rehabilitation group and 853(75.8%) in the standard care group. The baseline characteristics of the two groups are detailed in p = 0.41). The distribution of mRS at 90 days in two groups is presented in p < 0.01). Length of hospital stay was longer in the early rehabilitation group, with a median of 301 h, compared with 225 h in the standard care group (p<0.01). There were no significant differences in other secondary outcomes, including NIHSS at discharge and medical cost during hospitalization (The outcomes of the two groups are detailed in lization .p = 0.41) was not significantly associated with favorable functional recovery (mRS 0–2) at 90 days  effects of early rehabilitation in patients with AIS after EVT in real-world clinical practice. The main finding of this study demonstrated that patients with stroke receiving early rehabilitation had a lower death rate than those who did not receive rehabilitation during hospitalization. However, these clinically meaningful effects of early rehabilitation did not show on functional outcomes at 90 days. Although the proportion of favorable functional outcome (mRS 0–2) at 90 days was higher in the early rehabilitation group, no significant difference was recorded between the two groups in patients with LVO treated with EVT. In a randomized controlled study in A Very Early Rehabilitation Trial for stroke (AVERT), Bernhardt used subgroup analyses in patients receiving recombinant tissue plasminogen activator and found similar results, namely, no significantly favorable functional outcome at 3 months was observed in early rehabilitation group .Another finding of this study is that patients with stroke receiving early rehabilitation had a longer length of hospital stay than those who receive standard care during hospitalization. Length of hospital stay is the largest determinant of the direct cost for stroke care and is predominately determined by medical complications . This stThe main limitation of this study is the lack of unified records of rehabilitation protocol in the database. The rehabilitation data were based on self-reports from each center. The array of rehabilitation services delivered to patients with stroke in China is highly personalized and heterogeneous, varying in the duration, intensity, and type of interventions. The selection bias due to varied rehabilitation protocols provided across participating centers could not be neglected. Delivering rehabilitation in a standardized manner in all centers may address this issue. Some trials reported detailed protocols of the rehabilitation program, in which a unified training program was provided for the therapist to ensure consistency in rehabilitation treatment –27. Use The second limitation is that to minimize the effects on results, we exclude the patients without rehabilitation data and lost to follow-up, which may generate a selection bias since patients without rehabilitation data perhaps because they did not receive any rehabilitation, and those lost to follow-up possibly non-compliant with rehabilitation. However, we find that the demographic characteristics of two groups were not significantly different. Although there are differences in age, education level, prestroke mRS, and residual stenosis between two groups. In multivariate logistic regression analyses for outcomes, after adjusting for potential confounders, the results showed that there was no effect of potential confounders on outcomes , which mThe third limitation is that patients who initiated early rehabilitation with less abnormal mRS prestroke, lower residual stenosis, and other variables that might not have been registered. We used multivariate logistic regression analyses to examine whether these variables have effect on outcomes. In multivariate logistic regression analyses for outcomes, after adjusting for potential confounders Another limitation is that the study population could not reflect the general population with stroke as only patients with LVO after EVT were included, which means that the sample was relatively older (64.7 ± 12.2), and the proportion of patients with moderate to severe stroke (50% NIHSS≧16) was greater than a standard stroke population. This difference limits the generalizability of the results in the general stroke population. Other studies also observed negative results among patients with moderate stroke (NIHSS score ranging from 7 to 9) , 30. HenTo conclude, this study showed that patients with stroke receiving rehabilitation had a lower death rate than those who did not receive rehabilitation during hospitalization. However, these clinically meaningful effects of rehabilitation did not show on functional outcome at 90 days in patients with LVO after EVT.The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.The studies involving human participants were reviewed and approved by the IRB of Beijing Tiantan Hospital Affiliated to Capital Medical University. The patients/participants provided their written informed consent to participate in this study.YH and XN contributed to research project conception and design, statistical analysis, and manuscript writing. TH, XQ, ZC, WD, YW, and XL: data collection. YL: research project conception and design, statistical analysis review and critique, and manuscript review and critique. All authors contributed to manuscript revision, read, and approved the submitted version.This study was supported by the National Key R&D Program of China  and National Natural Science Foundation of China (81820108012).The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


Upper limb motor impairment (ULMI) rehabilitation is a long-term, demanding and challenging process to recover motor functionality. Children and adolescents may be limited in daily life activities due to reduced functions such as decreased joint movement or muscle weakness. Home-based therapy with Immersive Virtual Reality can offer greater accessibility, delivery and early rehabilitation to significantly optimise functional outcomes and quality of life. This feasibility study aimed to explore the perceptions and impacts of an immersive and interactive VR scenario suitable for ULMI rehabilitation for children at home. It was analysed using mixed methods  and from a multidirectional perspective . Amongst the main results, it was found that IVR for ULMI home rehabilitation (1) is easy to learn and acceptable; (2) improves motor function; (3) reduces the difficulty in the reproduction of therapeutic movements; (4) is motivating and enjoyable and (5) improves quality of life. This study is the first study on the use of IVR applied to home rehabilitation of ULMI in children. These results suggested that similar outcomes may be possible with self-directed IVR home rehabilitation compared to face to face conventional rehabilitation, which can be costly to both the patient and the healthcare system, decreasing the length of stay at the hospital and treatment duration. It has also presented an innovative solution to the Covid-19 emergency where children could not receive their clinic therapy. Further research is recommended to understand better the mechanisms involved in physiotherapeutic recovery and how IVR rehabilitation helps to improve conventional treatments.Trial Registration Protocol ID NCT05272436. Release Date: 9th March 2022. Paediatric Upper Limb Motor Impairments (ULMI) requiring rehabilitation affect a diverse population, including people affected by neurological, musculoskeletal and congenital conditions   program consisting of stretching, strengthening, positioning, splinting, casting and facilitation of movement focussed on high-intensity, repetitive and task-specific practice  system tailored for ULMI rehabilitation for children in their homes. Using feedback acquired through co-design with patients, caregivers and clinical staff, a new improved system specifically tailored for home use was developed.Selected outcome measures include ROM readings, quality of life (PedsQL), usability (SUS) and qualitative data (interviews).The redesign of the system builds on previous studies by incorporating additional immersive levels with new mechanics (arrow types) that replicate physiotherapy exercises . Usability required significant attention since the user would be using the system in their homes without instant support. This required the inclusion of a character that follows the user to provide tips on how to progress. Motivational challenges and engaging scenarios were implemented to maintain the users’ attention to prevent the therapy from failing, as is often the case with self-directed treatments.An aim of this study is to provide rehabilitation to paediatric patients with ULMI to optimise functional outcomes and overall well-being and quality of life. Utilising IVR technology with self-directed home rehabilitation, this system attempts to decrease healthcare pressure due to the Covid-19 pandemic by reducing clinic visits. This alternative approach to rehabilitation at home does not require supervised sessions. Although the therapist still needs to perform an initial assessment along with training on how to use the system, the subsequent follow-up appointments should be reduced with the improvement in adherence.VR scenarios can be presented through a head-mounted device (IVR), or a projection system or a flat-screen (non-IVR). The state of the art of clinical studies conducted to demonstrate the efficacy and acceptability of VR for ULMI rehabilitation has been primarily focussed on adults and non-immersive VR systems. There is a lack of clinical studies of IVR applied to children and in particular during home-based rehabilitation.Non-IVR environments provide visual feedback, presented through projection systems or flat screens. Biofeedback enables control of the timing of the task and supports motor learning (Kitago and Krakauer n = 30). Results showed significant improvements compared with the baseline measurements and significantly greater improvement in the experimental group compared with the control group (p < 0.05).The majority studies have been with adults with a focus on stroke patients. The randomised controlled trial (RCT) of Kiper et al.  with strn = 10; mean age 52). The games had positive effects on the shoulder abduction , adduction , wrist supination .Shahmoradi et al.  presente(n = 36) with CR. The experimental treatment was a non-IVR virtual reality-based system delivered via the Internet, which provided motor tasks to the patients from a remote rehabilitation facility with the therapist’s support. Results showed the Fugl-Meyer Assessment Upper Extremity (FMA-UE) indicated a significantly higher improvement in post-treatment motor function in the experimental group.As one of the first studies to evaluate the use of VR for ULMI rehabilitation after stroke, combining non-IVR and home-based approaches, Piron et al.  comparedn = 11). The patients trained with an inertial measurement unit (IMU)-based non-IVR system (ArmeoSenso) in their homes for six weeks. All subjects could use the system independently in their homes, and no safety issues were reported. The arm function of these patients improved significantly by 4.1 points (p < 0.003) in the FMA-UE. ArmeoSenso-based metrics showed an improvement in arm function, a high number of reaching movements (387 per session) and minimal compensatory activities of the trunk whilst training. Dodakian et al. (n = 12). Arm motor status showed significant gains , with half of the participants exceeding the minimal clinically significant difference.Based on self-directed therapy, a different approach was presented by Wittman et al. (2016), who conducted an open-label, single-group study with stroke patients . The system included a mobile device (tablet PC) for visualisation and a smartphone to obtain information about the movement of the affected arm using the built-in sensor. Findings showed that the system effectively promoted UL recovery in patients with stroke.Similarly, to empower patients to control their treatment at home, Choi and Paik  developeAll of the works included above use non-IVR systems, despite studies, suggesting that IVR using Head-Mounted Device (HMD) is more effective for upper limb motor recovery than non-IVR  with physical disabilities such as juvenile idiopathic arthritis (JIA), cerebral palsy (CP) and brachial plexus birth injury. Comparisons between LMCBT and CR groups showed similar results in all parameters in all disease groups (p > 0.05). Thus, this study has quantitatively shown that LMCBT should be an effective alternative treatment option in children and adolescents with physical disabilities.Recently, Tarakci et al.  developen = 80). Results showed a significant improvement in upper limb dexterity functions ), after treatment, significantly higher in the experimental group (DELTA = 10.09 ± 10.50) compare with the control group (DELTA = 3.65 ± 6.92) (p < 0.05).On the other hand, Choi et al.  carried Although the results found by these studies are relevant and demonstrate positive results, suggesting that non-IVR can help in the rehabilitation of children with ULMI, more research is needed for a broader range of clinical conditions and with systems with greater capacity for immersion and interaction.IVR environments are presented to the patients through a HMD, and this technology increases the user’s level of immersion (presence) in the environment. This plays an essential role in providing an optimal condition for task practice, as does the meaning of the task for the user (Kitago and Krakauer n = 12). Following the intervention, the primary outcome was that patients demonstrated a significant improvement in their motor function FMA-UE scores (p < 0.042) used to quantify the motor recovery status. One year later, . Both groups significantly improved the Barthel Index (BI) (p < 0.05), reflecting the recovery of UL motor function. The IVR-group revealed more significant improvements in FMA-UE scores (p < 0.05) than in the control group. Neural activity increased after the intervention, particularly in brain areas involved in the recovery of motor functioning, such as the primary motor cortex.Mekbib et al.  designedn = 8) with CP and developmental dyspraxia (DD). A two-period cross-over design was adopted for determining the differences between the proposed therapy and CR. Eight children were randomised into two groups: one group received the VERA treatment in the first period and the manual therapy in the second period and vice-versa for the other group. Results show both groups significantly improved their performance. No statistically significant differences were found between the two groups. The study suggested that IVR and wearable haptic devices are a viable alternative to CR for improving upper limb function in children with neuromotor impairments.The only study with children was carried out by Bortone et al.  and aimeThis review of related works has allowed us to conclude that VR can be used to improve ULMI rehabilitation, but that not much is known about the impact in the paediatric population, and that no studies have evaluated the feasibility, acceptability and perceived effectiveness of using an IVR system in particular for home rehabilitation and with children.Ethical approvals were obtained from NHS Health Research Authority ) and Sheffield Hallam University Ethics Review Committee (Ref. ER19710920). Permissions were also gained from local NHS Hospital Trust Research and Development (R&D) (Ref. SCH-2540). We recruited participants aged 7–16 from Sheffield Children’s NHS Foundation Trust (FT), who had sustained ULMI requiring rehabilitative care. Exclusion criteria included: 1) injuries to the face or head that could hinder the correct positioning of the HMD or pose an infection risk; 2) a learning impairment that could hinder the understanding of the task; 3) a history of severe motion sickness; 4) mental health problems and 5) inability to speak and understand English. Parents of eligible children, present during the rehabilitation treatment, were included in the study to provide feedback on their children’s experience with VR game and their perspective on using VR.Considering these criteria, eight patients, three boys and five girls, ages 7 to 16 years  and their eight mothers, participated in this study. Patients (Pt) had various UL injuries  was used by the physiotherapist to measure a Range of Movement (ROM) of the affected and unaffected upper limb join  before and after the at-home trial. This offered the opportunity to compare usual movement without an injury and the IVR rehabilitation.Paediatric Quality of Life Inventory (Version 4.0 – UK English) (PedsQL) is a standardised assessment for children aged 5–18 and was completed by patients before and after the IVR rehabilitation at-home trial. The scale features twenty-three items representing five dimensions: Physical, Emotional, Social and School Functioning  walking 100 m; emotional functioning (problems with…) feeling afraid or scared; social functioning (problems with…) getting along with other children; and school functioning (problems with…) paying attention in class). The instructions ask how much of a problem each item has been in the past month, and responses are on a five-point scale ranging from 0 (never a problem) to 4   is a quantitative scale to measure system usability completed by patients after the IVR rehabilitation at-home trial. It consists of 10 items with 5-point response options from Strongly agree to Strongly disagree  and by phone  with patients and parents after the IVR rehabilitation at-home trial. Four closed ten-point Likert questions provided a quantitative measure of the perceived ease or difficulty of use, pain levels and enjoyability of the IVR system. Open-ended questions provided qualitative data relating to difficulty, pain and enjoyability and participant attitudes towards the IVR system and its future deployment. Another semi-structured interview was conducted with the OT by the research nurse in person at the end of the trial to explore her attitudes towards the IVR system and future VR deployment. Both interviews were recorded, transcribed and anonymised.The OT was trained by a member of the research team to know how to use the IVR games and to be who recruited the patients, collected informed consent, gave out devices and administered the outcome measures.Before consenting to participate, each patient was offered a 5–10 min experience of the game to familiarise themselves with how it worked and to check for problems. If they agreed with the participation, written and verbal consent were taken from parents and children. After this, patients had, as in CR, a 20–30 min appointment in which the OT reviewed their previously prescribed home exercise regime with them, measured ROM and pre-trial PedsQL and explained and discussed new home exercises. For the at-home trial, patients were asked to use the IVR games to do their prescribed home exercises. Children were then asked to use the IVR system for approximately 15 min twice a day at home for three weeks.Following the at-home trial, patients and parents returned the equipment to the clinic in the final appointment, and the SUS and the post-trial PedsQL were administrated to the patient by OT in person. In addition, they participated in semi-structured interviews.At the end of the trial, an interview (10 min) with the OT was conducted by a research nurse.Quantitative data  were analysed and reported by descriptive analysis (median and range statistics) and means comparison (nonparametric: Wilcoxon signed-rank test Wilcoxon ) pre- anThe quantitative and qualitative analysis results will be presented in this section.The OT measured the ROM of the affected upper limb joint before and after exposure to IVR (5–10 min) and the unaffected upper limb to have a comparative value of the usual movement without an injury. As shown in Table Compared to healthy limb ROM measured at the same joint area, five of the eight patients achieved post-VR measures equal to the usual degrees of motion at some joint assessed Table .p ≤ 0.05).PedsQL results are shown in Tables n = 7), demonstrating high usability above the standard mean score of 68. In addition, patients strongly agreed with items such as "I think I would like to use the VR system frequently", "I found the VR system easy to use" and "I felt very confident using the VR system".The direct item scores were transformed, summed and converted to 0–100. The mean obtained by the patients was 99.64  of 4 and 3.43, respectively, showing that the VR system was easy to learn. In addition, patients reported not needing technical assistance before using the system.M = 9.29, ST = 0.951; M = 3.17, ST = 1.60; M = 1.33, ST = 1.75: M = 9.00, ST = 1.29).Quantitative data from the Likert questions showed that, in general, patients reported no difficulties in setting up and using the game, nor did they perceive pain when using it, with high levels of enjoyment as shown in Table Qualitative comments from all 15 participants  demonstrated positive impressions of and positive attitudes towards IVR during ULMI rehabilitation Table . ParentsThe content analysis generated two main themes. One theme related to “System Playability” was characterised by a process of “Learning and Mastery”. The second theme focussed on “Comparison of IVR with CR” and included sub-themes of: “Natural movements” and “Motivation to engage” Fig. . Data exIVR rehabilitation aims to facilitate the specific movements recommended by OTs in CR. In this study, the OT stated that this IVR intervention successfully reproduced the required exercises and combined all the movements she was looking for.M = 1.33, ST = 1.75). Qualitative data from parents suggested that they (6/7) did not witness pain in their children and perceived that children were not conscious of doing the rehabilitation exercises. Parent 8 reported that IVR reduced the fear and limitation of movement in her child with an external fixator, thereby helping her move naturally and unconsciously. As a result, she realised that she could do more than she had previously thought and achieved a better range of motion.Parents (5/7) observed that when their child was immersed in the game, he performed movements more fluently and naturally, without realising it. Similarly, most patients (4/7) and parents (6/7) indicated that the game made rehabilitation exercises easier to complete. This ease seemed to reflect both fluency of movement and lack of pain and fear. Reported pain levels were low .Patients (5/7) believed they would be more likely to complete their rehabilitation exercises with the IVR game at home. The IVR positively influenced their motivation and intention to carry on with the rehabilitation (6/7). Four noted that IVR rehabilitation was more fun and less boring, and quantitative data demonstrated high levels of enjoyment amongst participants  reported reducing the frequency of use after the first week due to repeatedly playing the same games. The greater motivational effects of IVR resulted in some parents (3/7) feeling less that they needed to remind and motivate their child with exercises. OT perceptions supported these findings that patients found the IVR game more interesting, engaging and motivating than usual exercises and that movement had improved.The best bits of the game reported by the patients were: shooting the arrows at the gnomes; seeing the score improve; rock climbing and falling; feeling challenged; being able to do different activities; graphics and animation. They also enjoyed being present in a virtual environment that they had never experienced previously. There were no worst bits reported from most patients (5/7). However, one patient (1/7) expressed that the worst was to have to do the levels before you can get onto the climbing one (Pt 2), and another (1/7) said that there are not that many games on it (Pt 4).Data extracts are found in Table Children and adolescents with ULMI often undergo a long-term, demanding and challenging rehabilitation process to recover motor functionality  data suggested that IVR rehabilitation could improve shoulder, wrist and elbow motor functionality, enhancing flexion, extension and abduction movements. The patients demonstrated ROM gains, in some cases even recovering the same degree of movement in the injured limb as the unaffected limb. These data are promising, indicating that all paediatric patients who have used our IVR game have improved their affected limb’s range of motion.Quality of life (PedsQL) scores also indicated a significant improvement after the IVR home trial compared to baseline scores. Physical and psychosocial health scores improved after the study, which may reduce the risk of long-term diseases such as chronic pain and disability  scores showed that patients generally understood the game mechanics well, and there were no critical errors that would have impeded the gameplay. For example, based on the patient's subjective report, no difficulty was found in setting up and getting used to the game. In this sense, we must point out the relevance of having the OT at the initial session, where they were shown how to use the game. Therefore, we encourage researchers and clinicians when proposing a self-directed session for children at home to include a first contact with the game accompanied by the OT or other healthcare professionals delivering the therapy. In addition, we recommend offering follow-up or support via telephone or email to solve potential problems during home ULMI rehabilitation.Furthermore, the positive results in learning and mastering the game may be explained by the inclusion of a tutorial at the beginning of the game, based on the findings of our previous study  reported they found it harder to get used to the game, whilst adolescents (aged 15–16) would like additional levels. This underpins future challenges in the development of IVR systems to support therapy across a broad age range of children. We recognise the need to maintain a certain difficulty level whilst being stimulating and providing meaningful activities during physical rehabilitation to ensure compliance, especially for children. There is scope for further development to ensure the right level of challenge and mastery for children of all ages. We plan to offer a broader range of difficulties in future iterations to ensure the enjoyment of those children who find it more difficult . In addition, this could positively affect self-confidence, self-esteem, attention span, concentration and interest in learning and, thereby, help to maintain motivation and compliance, as noted by previous researchers , and they can fail because of the patient’s lack of motivation affecting therapy , this allowed a comparison of CR to IVR rehabilitation in the qualitative feedback. Additionally, the VR system was used to treat a variety of ULMI, which allowed us to look at different aspects of interaction design and deployment considerations. Finally, using mixed methods  and from a multidirectional perspective  improved the breadth and depth of understanding of IVR acceptability.Future studies should examine IVR for clinical rehabilitation in a large-scale sample comparing the effectiveness of IVR rehabilitation with CR. In addition, to determine whether self-directed IVR home rehabilitation can be costly for both the patient and the healthcare system (Wang et al. Future research could further assist practitioners deliver their interventions by developing scenarios with mechanics which facilitate movements as yet unaddressed by the current system. A reporting system for the therapist to assess the patients progress and usage could provide staff with valuable information to determine the stage of healing and if the difficulty should be altered. Increasing customisation options to provide training tailored to the patient's abilities could help maintain attention. Adding more variety and valuable exercises for daily activities that are fun and challenging can increase motivation and adherence to treatment (Gerber et al. To summarise, this is the first feasibility study to trial IVR in the home rehabilitation of ULMI in children. The findings demonstrate that an IVR system has been developed capable of delivering ULMI therapy that leads to an increase in limb function, which is supported by the ease of use, enjoyment, adherence to the treatment, and can be delivered at home. It has also presented an innovative solution to the Covid-19 emergency where children could not receive their therapy in the hospital.