The student freedom of a tutor system

The scope of an ICAT ("Intelligent Computer-Aided Instruction") is to provide an environment for the student to learn efficiently and pleasantly. The student must then be free to try to solve the proposed problem using a strategy he thinks is the best one. The traditional way is using an expert system that solves the same problem and then compares both approaches. This behaviour is good enough to transfer the specialist knowledge for a beginner student, but it brings a restriction when learning a new subject. In medicine the diagnosis process is a graph search-like problem, where the physician determines a feasible way through all possible actions he can take at each moment (symptoms, historical data, etc.). He creates a path that he believes is the best way to achieve the desired goal, i.e., being able to explicit the cause of the troubles the patient presents. When a student is to learn how to work with the same situation, the system must give the student the knowledge used to find such a path. But the result of this process is better when instead of only saying to him what is to be done at each moment, the student is allowed to try his own ideas and giving him advice about each step through the path. A study and a specification of an ICAI to emergency medical service ("EMS"), that aims to help medical students when taking care of patients to be used in a University Hospital was developed. Before working with patients in EMS the student must practice.