The Arezzo Composer application is the developer's GUI. At the core of Arezzo are four different 'task' objects, from which more complex structures are built.
These are represented as follows:
Plans
Plans are designed to encapsulate strategies. A plan is a shell within which can be placed enquiries, decisions, actions and other plans.Enquiries
Enquiries, as the name suggests, are requests for information from the user. Enquiries can take many forms. Data values may be ranges of integers (or real numbers etc.); text entry from the user; multiple choice (with single or multiple selection); Boolean values or dates and times. It is generally the system that makes an enquiry to the user, effectively performing the routine of 'I have all this knowledge but I need to know which facts are salient to the problem we have at the moment.' Enquiries can be further manipulated by attaching 'pre-conditions' that need to be satisfied before the enquiry is fired. In this way the system only asks pertinent questions.Decisions
A 'decision' is the principal mechanism by which Arezzo reasons with its knowledge, the information it has gathered and facts it has established. It is an extremely powerful reasoning device. A 'decision' can be developed to generate heuristics from, and about, situations within the domain. They can be as general or as finely honed as necessary.Actions
Actions are procedures that need to be carried out in the 'outside world'. If Arezzo decides an 'action' needs to be carried out, it will present to the user and await confirmation that the 'action' has been done.Simple Arezzo Example
A simple example of an Arezzo guideline that uses all of the task types described above can be seen here
If this example were run by the Arezzo Performer engine, then the Enquiry task might request data about a patient’s clinical signs and symptoms. After this information was received, the Decision task would process the data values and then recommend options. Depending on which option the user chose, the guideline would then present the appropriate Action task. An example of this type of guideline can be viewed online at www.infermed.com/era, which is an early cancer referrals application for use by family physicians.
Arezzo guidelines can include multiple collections of the different task types. This means that complex clinical care protocols and guidelines can be created and run
