Background: ICBT started out as delivering self-help modules via a computer and/or the Internet, with or without additional therapist support. Today, ICBT is a broad class of services that may or may not include components such as interactive treatment content, text messaging, video communication, intelligent adaptation of content, data collection from external hardware such as wristbands, etc. There is a current lack of coherence in describing these services and their components. This lack of standards makes it impossible for services to communicate with each other, unless they were explicitly designed for this.

Method and Results: We believe that one way to address this problem is to reason about ICBT services on an abstract level. In this talk, we will describe how we created an abstract specification of an existing guided self-help ICBT service and how we implemented this specification as an application programming interface (API). This enabled us to develop several different front ends that each could communicate with the ICBT service through the API. In addition, we will describe how one of our front end applications could be used for two different ICBT services, once these services were designed to communicate through one standardized API.

Discussion: ICBT is evolving and could be even more integrated with external services and hardware. We believe that reasoning about ICBT on an abstract level and implementing functionality through APIs will help ICBT to develop even further.