Preferred Specimen/Attribute Status

Code	Description	Comment	Version
A	Alternate	This is a specimen that is acceptable as a replacement for a preferred specimen. In the following field (OM4-17), the sequence number of the preferred specimen must be messaged.	added v2.8
P	Preferred	This specimen is Preferred for all attributes (Container and Additive) identified in the OM4 segment.	added v2.8