Development of a Multidimensional App-Quality Assessment Tool for Health-Related Apps (AQUA)

Background: A multitude of health-related mobile applications are available to the public in app stores. Many of these apps were not developed by health professionals and are not scientifically valid. To facilitate a safe handling and use of such apps, it is important to assess their quality in a standardized way. Some instruments for app quality assessment already exist, although they have some limitations, which we want to improve upon with a new multi-dimensional assessment tool. Objectives: The objective of this paper is to explain the development of a new multidimensional criteria-based tool for the quality assessment of health-related apps (AQUA). Method: Based on existing app-quality assessment tools and guidelines for evaluating health-related app-quality, questionnaire items were constructed to assess the quality of mHealth apps from the perspective of both experts and users. Before the finalization of the questionnaire that would form the basis of AQUA, we conducted a pretest of the original German items with six participants, who gave qualitative feedback on the items while filling them out as they completed the surveys. Results: An expert and a user version of AQUA were developed in English and German. The expert version consists of 31 items in seven dimensions: Usability; User Engagement; Content; Visual Design; Therapeutic Quality; Security; and Information. The user version consists of 31 items in the following dimensions: Usability; User Engagement; Content; Visual Design; Therapeutic Quality; Impact; and Information. Conclusion: AQUA is a brief multidimensional app-quality assessment tool that can be used by experts and appusers to quickly determine the quality of health-related and mental health-related apps.