Ontology services

DRAFT - this article is in a very draft state and must not be relied upon as being up to date or an actual reflection of the world's true state.

The Information model service is a set of services that enables the Discovery common information model to be created, updated, distributed and accessed.

The service includes a set of web applications and a set of APIs to an information model server and an information model distribution service

All components of the service are open source and available at the Discovery Endeavour githubs https://github.com/endeavourhealth and https://github.com/endeavourhealth-discovery

The information model itself is internally defined via the Discovery_information_model_language which is a group of standards based languages with some pragmatic additions that enable the service to operate.  Externally, the Information model can be accessed via standards based APIs or by Discovery language based APIs that are supported by the Information model server.

The following lists the functional groupings of the IM Service. Some of these use web applications , some use the information model server, and some use the information model distribution service components that maintain locally owned copies of the information model.

Support for Value sets

The service supports the creation of, maintenance of, distribution of, and access to value set definitions and value sets, sometimes referred to as reference sets or concept sets.

A value set definition is a collection of concept expressions that have been brought together for particular business purposes. They are different from standard concept definitions because the meaning of some members of a value set may not be subsumed by the implied meaning of the value set. Value set definitions are desribed in more detail in the Discovery_Information_model_language.

A value set is a class whose members are class expressions i.e a Value set has members who are class concept expressions.

Class expressions may be simple pre-cordinated concepts such as a disease term like 2019 novel coronavirus detected or may be complex classes such as 

Covid 19 {EquivalentTo : Disease 

                and(causative_agent some coronavirus-2)

               and(has_pathological_process some infectious_process)}.

 

Value set editor

The value set editor enables people to create and maintain value set definitions which can then be downloaded, accessed via an API or distributed via the information model distribution service. 

Value set run time generator 

The value set generator returns a list of concepts that are defined by a value set definition for use in queries, thus supporting advanced subsumption_testing against health care records.

The value set generator API accepts the IRI of a value set either in full, or relative to a baseline IRI e.g. http://DiscoveryDataService/InformationModel#VSET_Covid1 or simple VSET_Covid1, and returns a list of concepts to be used in the query. The API supports both core concepts and original codes that have been mapped to the core concepts, depending on whether the database uses Discovery concepts or actual original codes

 

Value set distributor

The value set distributor maintains tables of value sets for databases that use local instances of the Discovery information model. 

This is part of the information model distribution service that runs on an application server,  and is designed to detect changes to the content of the information model and regenerate the value sets from the value set definitions. The value sets are regenerated whenever a value set definition changes or whenever there is an update to the concepts within the information model.