Data entry by physicians is a critical aspect in the health care domain, in which errors may lead to severe consequences for patients. This paper describes and discusses these aspects to support human-centered design of appropriate human-computer interaction technology. The following issues will be addressed, including system aim, users' profiles, interaction devices and environment of use, to cite the most important. Our work is based on a literature survey, questionnaires, and an active participatory design process conducted with healthcare professionals. Since the crucial factor is context of use, we elicited several relevant contextual attributes that enabled us to create and incrementally upgrade a context model. This conceptual model is intended to support a scenario-based design approach of future data entry systems. A few scenarios are provided