Objective: Serious Games is a field of research that has evolved substantially with valuable contributions to many application domains and areas. Patients often consider traditional rehabilitation approaches to be repetitive and boring, making it difficult for them to maintain their ongoing interest and assure the completion of the treatment program. Since the publication of our first taxonomy of Serious Games for Health Rehabilitation (SGHR), many studies have been published with game prototypes in this area. Based on literature review, our goal is to propose an updated taxonomy taking into account the works, updates, and innovations in game criteria that have been researched since our first publication in 2010. In addition, we aim to present the validation mechanism used for the proposed extended taxonomy. Materials and Methods: Based on a literature review in the area and on the analysis of the contributions made by other researchers, we propose an extended taxonomy for SGHR. For validating the taxonomy proposal, a questionnaire was designed to use on a survey among experts in the area. Results: An extended taxonomy for SGHR was proposed. As we have identified that, in general, and besides the mechanisms associated with the adoption of a given taxonomy, there were no reported validation mechanisms for the proposals, we designed a mechanism to validate our proposal. The mechanism uses a questionnaire addressed to a sample of researchers and professionals with experience and expertise in domains of knowledge interrelated with SGHR, such as Computer Graphics, Game Design, Interaction Design, Computer Programming, and Health Rehabilitation. Conclusion: The extended taxonomy proposal for health rehabilitation serious games provides the research community with a tool to fully characterize serious games. The mechanism designed for validating the taxonomy proposal is another contribution of this work.

Serious Games is a field of research that has evolved substantially with valuable contributions to many application domains and areas. Patients often consider traditional rehabilitation approaches to be repetitive and boring, making it difficult for them to maintain their ongoing interest and to assure the completion of the treatment program. This paper reviews Serious Games and the natural and multimodal user interfaces for the health rehabilitation domain. Specifically, it details a framework for the development of Serious Games that integrates a rich set of features that can be used to improve the designed games with direct benefits to the rehabilitation process. Highlighted features include natural and multimodal interaction, social skills (collaboration and competitiveness) and progress monitoring. Due to the rich set of features supported by the framework, the games' rehabilitation efficacy can be enhanced primarily from an increase in the patient's motivation when exercising the rehabilitation tasks.

This chapter addresses up-to-date research development regarding the adoption of more natural forms of interaction in the Serious Games for Rehabilitation domain of application. The chapter starts by presenting fundamental concepts on Serious Games illustrated by relevant applications. It describes the main problems involved and how Serious Games can benefit the process of rehabilitation. A comprehensive literature survey is presented and accompanied by a proposed set of classification criteria towards a taxonomy. From this study, a main research opportunity the authors identified is the potential benefits of the adoption of natural interaction modalities. The remainder of the chapter presents the authors’ recent work on this subject, including the description and design of game prototypes using alternative and natural interaction modalities. The chapter presents experiments and the results of a user study in order to make it possible to conclude about the benefits of the newer forms of interaction. From this study, it was concluded that the introduction of the natural interaction modalities has increased the attractiveness and intuitiveness of the prototyped Serious Game. This important result is a motivating factor to improve the interaction mechanisms and conduct studies with distinct tasks and larger samples of users/patients. Lastly, the authors report identified research opportunities and open problems.