As we model diagnostic orders and order items, I have not been able to find any particular examples of when an order would have multiple order items. An order for a CBC panel is simply a CBC order, but it has results for (Diagnostic Report and Observation) WBC, RBC and so on.
Is the intention that order items (specific investigations) are (for example) the individual orders of an order set? Or, is the intention that some configuration of an order would consist of multiple detailed 'investigation steps'?
If the former (order set) how would a FHIR client tell the difference between an order item and the set (there isn't any distinguishing attribute in the order item array).
If the latter, can someone provide a clinical example of how it would be used?
Any pointers (other than null) would be greatly appreciated!