Hi, Gary.

Here is an idea to resolve this problem: You can use a lookup table; just insert the data of the Patient Class (PV1-2) you want to map into the final result in Placer Field 1(OBR-18).

Here is an example of the table:

You can check more about this topic: Defining Data Lookup Tables | Configuring Productions | InterSystems IRIS Data Platform 2025.1

And assuming you are using 2.3.1:ORM_O01 as Doc Type. You need to add a condition to check if ORC-1 is equal to "NW", and if it is, you need to add this action:

Action: set

Property: target.{ORCgrp(1).OBRuniongrp.OBRunion.OBR:PlacerField1}

Value: ..Lookup("Prosthetics.orders.PatientClass", source.{PIDgrp.PV1grp.PV1:PatientClass},"O",3)

I assume "ORCgrp(1)" that group has only one record; otherwise, you need to use a for each loop. 

I hope that solution can help you.