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Healthcare Classifications and Terminologies


This subject guide was created to provide information on where to go for source documentation on various clinical terminologies and classifications that are used in health care.  Some of these systems are used to classify and aggregate diagnoses and procedures.  Other systems are identified as standards for accurately recording and expressing structured data in electronic health record systems.

Accurate reporting of data using these clinical terminologies and classifications requires an understanding and adherence to the coding rules, conventions, standards, and guidelines related to these systems.  The data are worthless if coding systems are used without regard to these coding rules, conventions, standards, and guidelines.

Do “classification” and “terminology” mean the same thing?

A classification arranges terms according to established criteria into groups or categories.  A terminology represents a set of terms that are used in a particular field.  Not all terminologies arrange terms into groups or categories.  Classification and terminology are not synonymous terms.

What is coding?

Coding involves the assignment of identifiers to represent a concept.  Such a definition can apply to classification but it is not limited to classification.  Codes can be used as identifiers for processing and facilitating exchange of data between computers.