1. Developing an Ontology for Randomised Controlled Trials
Henry Potts & Sanjay Modgil
Design-a-Trial team,
University College London

2. Randomised controlled trials
‘Gold standard’ in clinical research
Units randomly assigned to groups, in which intervention(s) are compared to a control and an outcome measured
Not restricted to medicine (agricultural products, advertising, archaeological conservation)

3. Design-a-Trial http://www.design-a-trial.net
Decision support software to aid inexperienced clinicians write a protocol for a randomised controlled trial (RCT)
Critiquing, pre-emption, natural language generation, ...
Back-end: Prolog; user interface: Visual Basic

4. An ontology A structure to encode data about RCTs
Used as basis for Design-a-Trial v.2 [Sanjay’s talk]
Propose as an Interlingua for other trial software

5. History EON/GLIF-2 for guidelines, not trials
BreastCancerProto.pont ProtegeWin example
concentrating on procedural aspects
Our RCT ontology
Ongoing work by Tu, Noy etc.

6. Trial_Model_Entity GLIF-2 etc. are bipartite in structure
Guideline_Model_Entity (procedural)
Reference_information
Our ontology is tripartite
add Trial_Model_Entity
Allows representation of trial-level concepts
Trial architecture, Outcomes, Interventions, Randomisation, ...

7. Multiple superclasses
Protégé allows multiple superclasses
links different levels of representation
crossing Guideline_Model_Entity vs. Trial_Model_Entity divide
ties Outcome_measure to an Action_Step
Thanks to...
Samson Tu for this paradigm shift

8. Guideline_Model_Entity changes
GLIF uses an ordinal time structure
Introduce temporal referents
Composite steps

9. Reference_information changes
Activity
Compliance_procedure
Consent_procedure
Structure of Intervention_procedure
Outcome_variable etc.

10. Conclusions Copy of (mostly) documented ontology available
Aim to make it downloadable from the web site and write up for publication
DaT going into commercial development