Principles of gamification for Internet interventions.

Gamification is a popular method used to add entertaining and appealing dimensions to nongaming activities. Researchers of technology-based behavioral and mental-health-focused interventions have shown considerable interest in gamification to enhance engagement and adherence. There have been a number of gamification frameworks proposed, each with differences in focus but with overlapping similarities. A review of these frameworks highlight critical issues in gamification-lack of clear definitions, standards, and a need for an overarching model for applying gamification, rather than simply describing gamification. These issues leave researchers challenged to apply gamification to its full potential. This paper explores gamification as a construct and endeavors to define its core features. A useful way of evaluating the potential utility of gamification features in the context of an intervention is by distinguishing between exogenous applications of gamification (layering game mechanics externally upon a system) and endogenous application of gamification (developing mechanics intrinsic to the given experience). By then comparing and contrasting six gamification frameworks, components are identified that lay at the intersection and a theoretical model is proposed. A theory-driven set of gamification principles, organized into four categories, is developed and presented. Of particular interest is the utilization of this model as it relates to behavioral and mental-health-focused Internet-based interventions. To demonstrate the potential of this gamification framework, the generated principles are overlaid onto the established Model for Internet Interventions, extending it, and providing a more concrete foundation for researchers of Internet interventions. The presented model will assist researchers and developers who are interested in applying gamification to Internet interventions.