EDIFACT message guide · Healthcare and social

MEDREQ Medical service request

The UN/EDIFACT message a requester sends a service provider to order investigations, or to change or cancel an order.

Sent by
Requesting clinician, practice or hospital
Received by
Laboratory or other service provider
Standard
UN/EDIFACT · Batch message
X12 equivalent
No direct equivalent

What is the EDIFACT MEDREQ message?

MEDREQ is the UN/EDIFACT medical service request. The directory defines it as a message sent from a service requester to a service provider to order investigations, to modify a previous order or ordered investigation, or to cancel a previous order.

Laboratory tests and other investigations are ordered electronically so the provider receives the patient identification, the tests requested and clinical information without transcription. Results come back in MEDRPT. Many health systems now use HL7 standards for the same purpose. Orders can be changed or cancelled.

How the EDIFACT MEDREQ message worksDiagram of the UN/EDIFACT MEDREQ Medical service request message. Requesting clinician, practice or hospital sends it to laboratory or other service provider. It usually starts the exchange. It is usually followed by MEDRPT. Inside the UNB and UNH envelopes, the directory D.21A requires, in the start of message: BGM (Beginning of message) and body and segment groups: the required SG1 loop with PNA (Party identification) and the required SG2 loop with FCA (Financial charges allocation), GEI (Processing information), RFF (Reference) and DTM (Date/time/period). 4 conditional segment groups are listed by their trigger segment.How the EDIFACT MEDREQ message worksMedical service request: who sends it, where it fits and what the directory marks mandatory1 WHERE IT FITSUSUALLY FOLLOWSStarts the exchangeMEDREQSENDERRequesting clinician,practice or hospitalRECEIVERLaboratory or otherservice providerCONTRL syntax report back, if agreedUSUALLY FOLLOWED BYMEDRPTMedical service report2 WHAT DIRECTORY D.21A REQUIRESInterchange: sender and recipient IDsUNB … UNZMessage MEDREQUNH … UNTSTART OF MESSAGEBGMBeginning of messageBODY AND SEGMENT GROUPSMandatory group SG1 · repeats up to 99PNAParty identificationMandatory group SG2 · repeats up to 99FCAFinancial charges allocationGEIProcessing informationRFFReferenceDTMDate/time/period+ 4 conditional groups, starting with:SCCDOCATTAUTBlue box: mandatory segment group. Conditional groups are listed by the trigger segment that starts them; a group is sent only when its data applies.Conditional segments outside groups are not drawn.Structure: mandatory segments and groups in the UN/EDIFACT directory D.21A listing for MEDREQ. Your trading partner's implementation guide adds itsown requirements.
How the EDIFACT MEDREQ message worksDiagram of the UN/EDIFACT MEDREQ Medical service request message. Requesting clinician, practice or hospital sends it to laboratory or other service provider. It usually starts the exchange. It is usually followed by MEDRPT. Inside the UNB and UNH envelopes, the directory D.21A requires, in the start of message: BGM (Beginning of message) and body and segment groups: the required SG1 loop with PNA (Party identification) and the required SG2 loop with FCA (Financial charges allocation), GEI (Processing information), RFF (Reference) and DTM (Date/time/period). 4 conditional segment groups are listed by their trigger segment.How the EDIFACT MEDREQmessage worksMedical service request: who sends it, where itfits and what the directory marks mandatory1 WHERE IT FITSUSUALLY FOLLOWSStarts the exchangeMEDREQSENDERRequestingclinician,practice orhospitalRECEIVERLaboratory orother serviceproviderCONTRL syntax report back, if agreedUSUALLY FOLLOWED BYMEDRPTMedical service report2 WHAT DIRECTORY D.21A REQUIRESInterchange: sender and recipient IDs(UNB … UNZ)Message MEDREQ (UNH … UNT)START OF MESSAGEBGMBeginning of messageBODY AND SEGMENT GROUPSMandatory group SG1 · repeats upto 99PNAParty identificationMandatory group SG2 · repeats upto 99FCAFinancial charges allocationGEIProcessing informationRFFReferenceDTMDate/time/period+ 4 conditional groups, starting with:SCCDOCATTAUTBlue box: mandatory segment group. Conditionalgroups are listed by the trigger segment thatstarts them; a group is sent only when its dataapplies. Conditional segments outside groups arenot drawn.Structure: mandatory segments and groups in theUN/EDIFACT directory D.21A listing for MEDREQ.Your trading partner's implementation guide adds itsown requirements.

How to read this diagram: the top row shows who sends MEDREQ, to whom, and which messages usually come before and after it. The lower part shows what the directory D.21A itself requires: the envelopes around MEDREQ and the segments and segment groups it marks mandatory. Conditional groups are listed by their trigger segment rather than drawn in full. This is the directory's minimum, not a trading partner's requirement: a message implementation guide, such as an industry subset or a partner’s own guide, usually makes some conditional groups mandatory, restricts the codes and may use an older directory.

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When it is used

  • Ordering laboratory tests
  • Modifying or cancelling ordered investigations
  • Requesting other diagnostic services

Where it fits in the message flow

This message MEDREQ Medical service request
Usually followed by MEDRPT Medical service report

Structure

Mandatory segments in MEDREQ (directory D.21A)

In UN/EDIFACT directory D.21A, the MEDREQ message has 114 segment positions arranged in 17 segment groups. These are the segments and segment groups marked mandatory at message level, in order; a mandatory group is shown with the segment that starts it. Segments inside conditional groups are needed only when the group is used. This is the directory’s requirement, not your trading partner’s: each partner’s message implementation guide names the directory it uses, often an older one such as D.96A or D.01B where the structure can differ, makes some conditional segments mandatory and restricts the codes.

  • UNH
  • BGM
  • SG1 (PNA)
  • SG2 (FCA)
  • UNT

Practical example

MEDREQ in practice

A general practitioner orders blood tests for a patient. The practice system sends the laboratory a MEDREQ with the patient's identification, the tests requested and relevant clinical details. The laboratory registers the order when the sample arrives and later returns the results with MEDRPT.

Implementation

Implementation considerations for MEDREQ

  • Comply with health data protection laws.
  • Use test codes the laboratory recognizes.
  • Identify patients reliably to avoid mismatched results.
  • Check whether partners use HL7 or another national standard instead.

Need help with MEDREQ?

ECOM maps, tests and monitors EDIFACT messages for your trading partners and integrates them with your ERP.