The DSP (Display Data) segment carries pre-formatted, line-oriented text that an application can render directly to a screen or printer. It is used by responding systems that want to control exactly how a result or report appears, sending the response as a sequence of display lines rather than as discrete data elements. Each DSP repetition represents one line of output, optionally tagged with a display level, a logical break point, and the identifier of the result the line belongs to.
DSP is most commonly encountered in display-oriented query responses, where the sender has chosen the unsolicited display response (UDM) or display response (DSR) flavor of a Q/A interaction. In that role it is the display-mode counterpart of the RDT tabular row and the QRD query definition.
Used in
DSP carries formatted display data in DSR (display response) query/response messages — see QRY message. It is a building block of the display-result group used when the receiver expects to render lines rather than parse fields.
Field-by-field reference
The table below lists every field defined for DSP in HL7 v2.5.1 as exposed by the HAPI structure. The Seq column is the field identifier (DSP-1 through DSP-5), Req reflects HL7's optionality (R only where the standard requires the field), Repeat indicates whether the field is defined as repeating in the segment structure, and Table # references the HL7-defined value set when one is well established.
| Seq | Name | Data Type | Length | Req | Repeat | Table # | Description |
|---|---|---|---|---|---|---|---|
| DSP-1 | Set ID - DSP | si | — | O | — | — | Sequence number for this DSP repetition |
| DSP-2 | Display Level | si | — | O | — | — | Logical level or indent of the line |
| DSP-3 | Data Line | tx | — | R | — | — | Actual text content of the display line |
| DSP-4 | Logical Break Point | st | — | O | — | — | Marker identifying a logical page or section break |
| DSP-5 | Result ID | tx | — | O | — | — | Identifier of the result this line belongs to |
Examples
Minimal DSP
DSP|1||Hemoglobin: 13.8 g/dL
Fully-populated DSP
DSP|1|1|Patient: DOE, JANE MRN: 7741882|HDR|RPT-2026-0001
DSP|2|2| Hemoglobin .................... 13.8 g/dL (12.0-16.0)||RPT-2026-0001
DSP|3|2| Hematocrit .................... 41.2 % (36.0-46.0)||RPT-2026-0001
DSP|4|1|--- End of CBC panel ---|FTR|RPT-2026-0001
Annotated breakdown
DSP|1|1|Patient: DOE, JANE MRN: 7741882|HDR|RPT-2026-0001
| | | | |
| | | | +-- DSP-5 Result ID = RPT-2026-0001
| | | +------ DSP-4 Logical Break Point = HDR (header line)
| | +---------------------------------------- DSP-3 Data Line (rendered text)
| +------------------------------------------- DSP-2 Display Level = 1 (top level)
+---------------------------------------------- DSP-1 Set ID = 1 (first line of the display)
In-context excerpts
DSP inside a DSR^Q01 display response
MSH|^~&|LIS|MAIN_LAB|EHR|GENERAL_HOSP|20260610101500||DSR^Q01^DSR_Q01|MSG00041|P|2.5.1
MSA|AA|Q00041
QRD|20260610101500|D|I|RPT-2026-0001|||1^RD|7741882|RES|||
DSP|1|1|Patient: DOE, JANE MRN: 7741882|HDR|RPT-2026-0001
DSP|2|1|Accession: ACC-998132 Collected: 2026-06-10 08:42|HDR|RPT-2026-0001
DSP|3|2| Hemoglobin .................... 13.8 g/dL (12.0-16.0)||RPT-2026-0001
DSP|4|2| Hematocrit .................... 41.2 % (36.0-46.0)||RPT-2026-0001
DSP|5|1|--- End of report ---|FTR|RPT-2026-0001
DSC|CONT-00041|F
DSP carrying a printable encounter summary
MSH|^~&|REPORTS|CLINIC_A|PRINTER|FRONTDESK|20260610113000||DSR^Q01^DSR_Q01|MSG00042|P|2.5.1
MSA|AA|Q00042
QRD|20260610113000|D|I|VISIT-2026-7741882-03|||1^RD|7741882|VST|||
DSP|1|1|VISIT SUMMARY 2026-06-10|HDR|VISIT-2026-7741882-03
DSP|2|1|Provider: SMITH, ALAN MD Clinic: FAMILY MEDICINE|HDR|VISIT-2026-7741882-03
DSP|3|2| Chief complaint: routine follow-up||VISIT-2026-7741882-03
DSP|4|2| Assessment: stable hypertension||VISIT-2026-7741882-03
DSP|5|2| Plan: continue current medications, recheck in 3 months||VISIT-2026-7741882-03
DSP|6|1|Signed electronically by SMITH, ALAN MD|FTR|VISIT-2026-7741882-03
Implementation notes
- DSP-3 (Data Line) is the only required field; senders must always populate it, even with an empty visual line, because the segment has no meaning without text.
- DSP-2 (Display Level) is a hint to the receiver about indentation or hierarchy. Most renderers map it directly to leading whitespace or font weight, but its interpretation is application-defined.
- DSP-4 (Logical Break Point) is typically used to mark header (HDR), detail, and footer (FTR) lines, or to signal a page or section break for paginating output.
- DSP-5 (Result ID) ties a display line back to a logical result, allowing a single DSR to carry display data for multiple results without ambiguity.
- DSP repeats by being sent as multiple segments rather than as a single repeating field; each line of output is its own DSP segment with an incrementing Set ID.
FHIR mapping
The HL7 v2-to-FHIR Implementation Guide does not publish a segment-level ConceptMap for DSP. In practice, DSP is treated as narrative text and surfaced in FHIR as Composition.section.text or as the text element of whatever resource the display narrative belongs to, with the concatenated DSP-3 lines forming the human-readable block.
