Development of Performance Indicators for AAC Application Design and Usability Evaluation

Objectives: With advancements in scientific and technological progress, various Augmentative and Alternative Communication (AAC) applications (apps) have been developed. AAC users require AAC systems that align with their personal characteristics and needs. AAC performance indicators, which encompass usability evaluation, aim to measure communication effectiveness and satisfaction. These indicators can be utilized to assist AAC users in selecting appropriate AAC systems. The goal of this study was to develop performance indicators that would allow AAC users and stakeholders to evaluate AAC apps from multiple perspectives. Methods: Mobile apps and usability evaluations in prior studies were analyzed to extract keywords. Performance indicator items were developed based on this analysis. Expert validity was evaluated, and a survey of AAC users and stakeholders was done to adjust the number of items included and measure validity and reliability. Results: The analysis of prior studies for the development of performance indicator items was visualized in the form of a word cloud. The reliability assessment of AAC app performance indicators yielded a Cronbach’s α value of 0.9 or higher. Regarding content validity, the expert validity showed an S-CVI of 0.978, while the survey with AAC users and stakeholders resulted in 0.754. Exploratory factor analysis was performed to assess construct validity, revealing that all variables demonstrated a communalities value of 0.4 or higher. The items were categorized into five factors: usability, social communication, user-centered design, adoption, and empowerment. Conclusion: AAC app performance indicators should be user-centered, incorporating diverse perspectives and evaluating various aspects of app usage.