How to add an NTE after an OBX?

[bilago]

I'm using the latest NHAPI in a .net 6 project and generating an ORU_R01 message.
I wrote this method to add an NTE to an observation, but I cannot create an equivalent to put the NTE after the OBX.

public static void CreateNote(ORU_R01_ORDER_OBSERVATION orderObservation, string? comment)
{
    var nte = orderObservation.AddNTE();
    nte.SetIDNTE.Value = orderObservation.NTERepetitionsUsed.ToString();
    //see https://hl7-definition.caristix.com/v2/HL7v2.5.1/Tables/0105 for list of valid sources
    nte.SourceOfComment.Value = "L";
    nte.GetComment(0).Value = comment;
}

The issue is that while the observation class has an AddNTE() method, there is none for the OBX record. Why is that missing if it is acceptable to have an NTE after an OBX according to the HL7 standard (unless I'm mistaken)

[milkshakeuk]

That is because you don't add NTE to OBX you can add NTE to ORU_R01_ORDER_OBSERVATION which is what you are referencing above and you can also add NTE segments to ORU_R01_OBSERVATION which is what you are after.

Here is an example of what I think you are trying to do.

// your existing method
public static void CreateNote(ORU_R01_ORDER_OBSERVATION orderObservation, string? comment)
{
    var nte = orderObservation.AddNTE();
    nte.SetIDNTE.Value = orderObservation.NTERepetitionsUsed.ToString();
    //see https://hl7-definition.caristix.com/v2/HL7v2.5.1/Tables/0105 for list of valid sources
    nte.SourceOfComment.Value = "L";
    nte.GetComment(0).Value = comment;
}

// new method for observation notes
public static void CreateNote(ORU_R01_OBSERVATION observation, string? comment)
{
    var nte = observation.AddNTE();
    nte.SetIDNTE.Value = observation.NTERepetitionsUsed.ToString();
    //see https://hl7-definition.caristix.com/v2/HL7v2.5.1/Tables/0105 for list of valid sources
    nte.SourceOfComment.Value = "L";
    nte.GetComment(0).Value = comment;
}

...
// how to add the NTE after the OBX
oruR01.GetPATIENT_RESULT().GetORDER_OBSERVATION().GetOBSERVATION().CreateNote("note to add");
...

As a side note NET6 is out of support so is considered vulnerable to security exploits, I would consider updating to the current LTS at least which is NET8; should require minimal effort to do so.

[bilago]

Thank you, This was the answer, I feel silly for not realizing there was ORU_R01_ORDER_OBSERVATION AND ORU_RO1_OBSERVATION, which the latter was the one I was needing to add the NTE to. Once I made that change I'm now getting

OBR|1
OBX|1
NTE|1
NTE|2

versus before:

OBR|1
NTE|1
NTE|2
OBX|1

Regarding your supplemental comment regarding .net version - I agree with you but we're not approved for NET8 in prod yet.