Game Customization and Pace Effects on Movement Performance and the User Experience During Serious Games for Balance Among People After a Stroke: Cross-Sectional Repeated Measures Study.

Background: Serious games can be custom or noncustom, each offering advantages for rehabilitation. Custom serious games developed specifically for rehabilitation allow control over feedback and adjustment of game speed and difficulty. Alternatively, noncustom games do not offer these controls but provide attractive graphics, sounds, and engaging game mechanics. The differences between these systems may affect users' exercise intensity, quality of movement, and experience during gameplay, which have implications for system and game selection in rehabilitation. Objective: This study compared movement performance and user experience of patients after a stroke while playing custom and noncustom virtual reality balance games that were either game-paced or self-paced. Methods: A group of community-dwelling patients in the chronic phase post stroke participated in a cross-sectional repeated measures study. They were familiarized with 12 games; half were played using the custom system (Equio, Kinestica) and half with the noncustom system (Nintendo Wii Balance Board, Wii Fit games). Over 2 gameplay sessions with randomized blocks of game type (self-paced and game-paced) and the order of the system (custom and noncustom), participants played games requiring comparable movement of the center of pressure for each system. Movement performance (weight-shift repetitions and movement amplitude) was extracted from video recordings using the Kinovea software. User enjoyment (Modified Physical Activity Enjoyment Scale), flow (Flow State Scale for Occupational Tasks), and likability were assessed twice in each study block. Comparisons between the systems were conducted using paired t tests or Wilcoxon tests. Effect sizes (ES) were calculated using Cohen d. Results: Twenty-six participants (aged 27-70 years) were included in the analysis. Repetitions and movement amplitude were significantly greater (repetitions: P˂.001-.003; amplitude: P=.002-.03) with large ES for all noncustom game-paced games and for half of the noncustom self-paced games (repetitions: ES 0.8-2.5; amplitude: ES 0.6-0.9). Perception of exertion was greater for noncustom game-paced games (ES 0.6; P=.005). In contrast, users' flow state (total and subdomains of sense of control and emotional experience; ES 0.6-0.8; P≤.03) and user preference were significantly greater for custom game-paced games. There was no significant difference between custom and noncustom games for enjoyment. Conclusions: Serious gameplay was influenced by customization and type of game pacing, both of which should be considered when selecting serious games for balance training. Repetitions, movement amplitude, and perception of effort were greatest for the noncustom game-paced games, indicating greater intensity, while also addressing the difficulty patients after a stroke have with weight-shifting to the affected side. In contrast, custom games provided a sense of control and increased flow state, which may promote better adherence. Findings from this study have implications for clinicians and game designers. Both custom and noncustom games offer training features that support stroke rehabilitation.