The development of healthcare information systems is broadly considered a promising strategy to ensure, enhance and deliver of quality patient services, thus improving the healthcare economic sustainability [1]. However, their systematic evaluation needs to implement economic evaluation models that can help decision makers to determine a feasible and suitable analysis of the impact of an information system in the appropriate healthcare setting [2]. Aim of this paper is to define a mathematical model to provide an "ex-ante" measure of adequacy and significance in the adoption process of Electronic Healthcare Records (EHRs). In particular, the model establishes how different subjects (General Practitioners, GPs and patients) are involved in the testing process and how the resources provided can be invested to find out the most suitable intervention strategies.