Hacking Healthcare

Chapter 10. Ontologies

Practically speaking, an ontology is just a fancy word for a dictionary. More specifically, an ontology is a way of structuring knowledge, by coding complex concepts into simpler terms. Beyond that, ontologies vary widely in the level of complexity given to structuring the relationships between the terms. Some people use the term ontology in healthcare to refer to only systems that are capable of deeply modeling clinical information. Others use the term to refer generally to all types of abstract health care data sets. Sometimes, people speak about ontologies in terms of codes, code sets, or coding processes. This chapter will cover both important sources of clinical coding systems or ontologies, of several types.

The basic problem that clinical ontologies seek to address is the difficulty that automated processes have with synonyms. Heart attack, cardiac arrest, and myocardial infarction, as well as the acronyms MI or AMI, can all be used to describe the same event. Having multiple terms for the same thing is difficult if you want to fully automate any clinical information process. An ontology solves this problem by noting that the terms heart attack, myocardial infarction, MI, and AMI really are the same thing, and cardiac arrest, like cardiac arrhythmia are related terms, but not synonyms for those concepts.

Traditionally the academic study of ontologies has been of interest to philosophers, computer scientists, and cognitive scientists, who are deeply concerned ...