UCUM (Unified Code for Units of Measure) is defined by Regenstrief to allow a systematic computable approach to scientific units. In CDA, units of measurements must use UCUM, and UCUM can be used in HL7 v2. UCUM defines a systematic syntax for representing all units, and aslo defines codes for all known systematic units, such that most units can be represented in a human readable fashion that is non ambiguous. Note that common human systematic usage of codes (in scientific papers, text books etc) is ambiguous because some (non-SI) unit codes are reused in multiple contexts. The problem is that many non-SI codes are in common use in medical practice. UCUM is maintained at UnitsOfMeasure.org

HL7Connect includes a copy of UCUM, and uses that copy to provide the following UCUM services:

Updating the UCUM definitions

If mmore recent versions of UCUM have been released that contain units not known by HL7Connect, you can update the UCUM cache.

  1. You need a copy of an updated ucum-essence.xml file (from UnitsOfMeasure.org). You can modify it yourself prior to uploading if you want, to add, delete or modify units (though this is a very bad idea).
  2. Run the Manager
  3. Choose the Utilities Tab
  4. Click on the Import UCUM button
  5. Choose the Ucum-essence.xml file from step #1
  6. Once the import is complete, you need to restart HL7Connect

© Kestral Computing P/L 2000-2015. HL7Connect v2.00-063 generated on 30-Nov 2015
Keywords: UCUM, units