“Making the right choice for criteria and performance measures depends on understanding the alternatives available and the limitations of each.”
(Hartson et al., 2003, p. 153)
This chapter explores the resolution of our first research aim. It covers the establishment and refinement of criteria for developing a digital game for post-stroke rehabilitation. The three criteria that were assessed to be the most relevant were adaptability, connectivity and meaningful interactions. The final output game was specifically aimed at lower-limb rehabilitation, however these criteria act as generic principles and could be applied beyond this research.
4.1 Criteria for Success
Exploring existing knowledge in this field has made a number of things clear. Firstly, it is impossible to create a universally applicable game experience for everyone (Malone, 1981, p. 343). Secondly, for a game to function successfully as a physiotherapy aid it must prompt accurate therapeutic exercise and report relevant data (Lee et al., 2012, p. 435). Thirdly, in the amount of time available for this research it was not possible to explore all avenues of game design in detail and selected elements needed prioritisation. The game was still developed holistically (capable of existing as a standalone experience rather than just an experiment with mechanics) with elements that were deemed significant given greater attention.
4.1.1 Establishment of Criteria
Consultation with the clinicians generated a list of properties the system should exhibit to be effective as a physiotherapeutic aid.
Three criteria were chosen from this selection to be prioritised by the game.
The first criterion is adaptability. Dr. Signal emphasised the importance of “specificity to the individual” (personal communication, 10 August 2015). The three main points of adaptability that are covered by literature are: mode of input, difficulty and interface (Alankus et al., 2010, Gerling et al., 2010, Gerling et al., 2011, Gregor et al., 2002, Holden & Dyar, 2002, Ma et al., 2007, Mahmud et al., 2008, Moreira et al., 2010, Orvis et al., 2008, Sampayo-Vargas et al., 2013, Schönauer, Pintaric, & Kaufmann, 2011, Shirzad et al., 2015). Adaptable input methods are particularly important with rehabilitative games, as the system needs to be able to adjust as the user grows stronger. Ma et al. claim that this allows for the improvement of the patient’s residual capabilities “without causing fatigue and frustration” (2007, p. 683). It is also integral for the long-term usability of the system in both a clinical environment and in home-based rehabilitation (Alankus et al., 2010, p. 2121).
The significance of adaptive difficulty in games is the connection between challenge and engagement. If a game is too hard the audience will become frustrated with their inability to progress. If the game is too easy they will become bored. This concept is referred to as ‘flow theory’ (Mathwick and Rigdon, 2004, Sampayo-Vargas et al., 2013). If the game’s flow is engaging enough, it can even help players cope with pain (Lee et al., 2012, p. 436, Moreira et al., 2010). The problem remains that the flow’s balance resides in a different place for each user. Matters are further complicated by the target audience experiencing difficulty from physical limitations as well. Gregor et al.’s (2002) discussion on the variation of decline of physical and mental faculties in older adults makes it clear that any system being designed for this demographic must be able to adapt to a broad range of user needs.
Connectivity was found to be of recurring importance (Alankus et al., 2010, Binstock & George, 2001, Blythe et al., 2005, Costikyan, 2006, Flores et al., 2008, Gerling et al., 2011, Ijsselsteijn et al., 2007, Jack et al., 2010, Mahmud et al., 2008, Trefry, 2010) and therefore became the second criterion. Social isolation is one of the biggest issues faced by older adults, many of whom “feel a crippling sense of loneliness” (Blythe et al., 2005, p. 683). Whether users are dependent on others for health care, or simply desire social contact and support, the game system needed to enable social interaction. It was beneficial that digital games are widely perceived as an enjoyable means of maintaining social connections through common interest (Mahmud et al., 2008, p. 403).
To fully utilise the positive effects of connectivity in gaming, several things needed to be considered. Most importantly, as Blythe et al. write, “there is no substitute for human contact” (2005, p. 681). Solitary rehabilitation can be incredibly mundane but this can be remedied by local (offline) support. Face to face contact is a crucial part of traditional games that many digital games lack (Mahmud et al., 2008, p. 404) and many patients believe “they would more readily exercise if accompanied by someone else doing the activity” (Jack et al., 2010, p. 227). Sharing an experience with another person can generate interpersonal motivations, which is particularly important when the individual has reduced self-efficacy (Moreira et al., 2010).
The option to play with people who are either impaired or unimpaired would be beneficial as users may prefer one to the other. For example; one player may feel discriminated if they are the only one using a device, in contrast to someone who simply wishes to play with their grandchildren. Therefore the game needs to be functional without exercise-based interactions.
4.1.4 Meaningful Interactions
The third and final criterion was meaningful interaction with the system. This concept represents the system’s ability to communicate its purpose through gameplay. This can manifest as the game supporting the player’s extrinsic motivations. Interaction with the system generates meaning through its salience to the player. Ijsselstein et al. reinforce the significance of this criterion, claiming many older adults disregard new experiences due to a lack of perceived benefits (2007, p. 19). Such perspectives generate a problem in physiotherapy where the lower-order tasks required for rehabilitation seem too mundane to bother with. They lack context and positive reinforcement (McPherson et al., 2014, p. 110).
Task-oriented exercises are a common means of improving the salience of motor learning (Shirzad, 2015, p. 361), as they situate the exercise within a context relevant to the user. For example; a survivor of stroke is an enthusiastic drinker of tea, yet the shelf that holds their mugs is level with their shoulder. The task their clinician sets may involve lifting a ceramic mug up to shoulder height with an extended arm. The patient is more likely to attribute this task to a positive experience and may be more motivated to complete it.
Tasks within a physiotherapy game can be functionally similar. Nunes & Dreze claim that people often exhibit persistence in achieving goals that have discrete, extrinsic rewards (2006, p. 504), therefore in-game features such as achievements (e.g. badge or trophy systems for accomplishments like “won five matches in one day”), progress tracking (such as levels, rankings or personal analytics), or in-game objectives (such quests, tasks or daily goals) have the potential to increase extrinsic motivation by rewarding players for interacting with the system. Such interactions could be interpreted as salient through their ability to realise the goals of the player.
Gregor et al. recommend game designers use “meaningful metaphors and relate real world actions” (2011) to improve accessibility to an older audience. What can be deemed “meaningful” will differ from person to person, however mapping in-game actions to logical real-world motions is less subjective. Players of rehabilitation games are likely to have the extrinsic motivation of improving their health, thereby rewarding players who complete exercises could help them maintain motivation to play the game. Logical connections between a player’s exercises and the in-game response could reinforce the game’s purpose as a rehabilitation aid.
4.1.5 A Criteria-based Thesis Model
These criteria were core components of the following design phase. Much like the designs, the criteria were subject to an iterative process, being refined as the research developed to best represent the ideal outcome. As developments were made the weighting of the criteria became more defined.