• • • sending LOINC codes back: we believe this to be a mistake:  The mapping spreadsheet shows those extensions are intended to be a part of the payload.  In addition the extension should have the diagnosis and modifiers as 0..* instead of having to repeat the extension multiple times

Current design requires that you create a PASCommunicationRequest for each Loinc/loinc modifier pair.

Claim Response has a reference to PASCommunicationRequest:

The PASCommunicationRequest has added extensions at the top rather than the payload:

CommunicationRequest		0..*	CommunicationRequest	A request for information to be sent to a receiver
id	Σ	0..1	string	Logical id of this artifact
meta	Σ	0..1	Meta	Metadata about the resource
implicitRules	?!Σ	0..1	uri	A set of rules under which this content was created
language		0..1	code	Language of the resource content Binding: CommonLanguages (preferred) Max Binding:  AllLanguages: A human language.
text		0..1	Narrative	Text summary of the resource, for human interpretation
contained		0..*	Resource	Contained, inline Resources
extension		0..*	Extension	Extension Slice: Unordered, Open by value:url
extension-communicatedDiagnosis	S	0..1	CodeableConcept	Optional Extensions Element URL: http://hl7.org/fhir/us/davinci-pas/StructureDefinition/extension-communicatedDiagnosis Binding: X12 278 Diagnosis Code Value Set (required)
extension-contentModifier	S	0..1	CodeableConcept	Optional Extensions Element URL: http://hl7.org/fhir/us/davinci-pas/StructureDefinition/extension-contentModifier Binding: X12 278 Diagnosis Information Type (required)

Move these extensions DOWN to the payload.