Data Values

JSON Primitives

The following JSON primitive types are a subset of the openEHR Foundation Types, and are represented in SDF in their native JSON form.

Formal type Definition Example

Boolean

"true" | "false"

Integer

JSON integer

5
124000

Real

JSON number

5.0
6.023e23

String

JSON string

"mild anaemia"
"a line of text\n"

openEHR Primitives Represented as JSON String

The following are openEHR primitive types represented as JSON Strings which may be parsed to instantiate the appropriate data type.

Formal type Definition Example

Character

JSON character

 
"k"
"\t"

Iso8601_date

ISO 8601 date string, including partial forms; see TIME_DEFINITIONS.valid_iso8601_date().

 
"2020-04-01"
"2020-04"
"2020"

Iso8601_time

ISO 8601 time string, including partial forms; see TIME_DEFINITIONS.valid_iso8601_time().

 
"13:45:00"
"13:45"
"13"
"13:45:00.722+03:00"
"13:45+03:00"

Iso8601_date_time

ISO 8601 date/time string, including partial forms; see TIME_DEFINITIONS.valid_iso8601_date_time().

 
"P2Y4M10D"
"P1DT3H"
"PT2h5m0s"

Iso8601_duration

ISO 8601 duration string; see TIME_DEFINITIONS.valid_iso8601_duration().

 
"P2Y4M10D"
"P1DT3H"
"PT2h5m0s"

Uri

RFC 3986 string

 
"https://www.openEHR.org"
"http://snomed.info"

Terminology_code

openEHR ODIN TERM_CODE_REF, defined as "[<terminology_id>::<code>]" | "[<terminology_id>(<version_id>)::<code>]"

 
"[icd10AM::F60.1]"
"[snomed_ct(2020_06_01)::3415004]"

Terminology_term

openEHR ODIN XXXX, defined as "[<terminology_id>::<code>|<text>|]" | "[<terminology_id>(<version_id>)::<code>|<text>|]"

 
"[icd10AM::F60.1|Schizoid personality disorder|]"
"[snomed_ct(2020_06_01)::3415004|cyanosis|]"

TBD: S.I.: there is no support for version_id in Terminology_code / Terminology_term, or value in Terminology_term.

EhrScape Variants

EhrScape variants exist for the following types.

Formal type EhrScape Format

Terminology_code

 
{
    "|code": "238",
    "|terminology": "openehr"
}

Terminology_term

 
{
    "|code": "238",
    "|value": "other care",
    "|terminology": "openehr"
}

openEHR Intervals Represented as JSON String

Data instances of type Interval<T: Ordered>, where the concrete descendants of Ordered are shown in the openEHR Foundation Types are represented in SDF templates as JSON Strings containing openEHR ODIN intervals, for example "|08:02 .. 09:10|".

The interval syntax is summarised as follows:

    |N .. M|        -- the two-sided range N >= x <= M;
    |> N .. M|      -- the two-sided range N > x <= M;
    |N .. <M|       -- the two-sided range N <= x <M;
    |> N .. <M|     -- the two-sided range N > x <M;
    |< N|           -- the one-sided range x < N;
    |> N|           -- the one-sided range x > N;
    |>= N|          -- the one-sided range x >= N;
    |<= N|          -- the one-sided range x <= N;
    |N +/-M|        -- interval of N ±M;
    |N±M|           -- interval of N ±M.

Examples of this syntax include:

    |0 .. 5|              -- integer interval
    |0.0 .. 1000.0|       -- real interval
    |0.0 .. <1000.0|      -- real interval 0.0 <= x < 1000.0
    |08:02 .. 09:10|      -- interval of time
    |>= 1939-02-01|       -- open-ended interval of dates
    |5.0 ±0.5|            -- 4.5 ±5.5
    |5.0 +/-0.5|          -- 4.5 ±5.5
    |>= 0|                -- >= 0

Lists of Primitive Type and Intervals

Lists are represented in the standard JSON manner, with the elements represented as described above. The following shows various examples.

    ["cyan", "magenta", "yellow", "black"]
    [1, 1, 2, 3, 5]
    ["[icd10AM::F60.1]", "[icd10AM::F64.2]"]

openeHR Reference Model DATA_VALUE Types

All openEHR RM DATA_VALUE types can be represented in SDF form. Many have the same representation as the Foundation types on which they are based and are assumed to be instantiated to the correct RM type by virtue of parsing within a model-available context. These are shown in the following table.

Formal type Definition

DV_BOOLEAN

See Boolean

CODE_PHRASE

See Terminology_code

DV_TEXT

See String

DV_CODED_TEXT

See Terminology_term

DV_COUNT

See Integer

DV_DATE

See Iso8601_date

DV_DATE_TIME

See Iso8601_date_time

DV_TIME

See Iso8601_time

DV_DURATION

See Iso8601_duration

DV_EHR_URI

See Uri

The DATA_VALUE types that have specific SDF syntax forms are shown in the following table.

Formal type Definition Example

DV_ORDINAL

"<ordinal_value>|<terminology_code>" |
"<ordinal_value>|<terminology_term>"

"1|[snomed_ct::313267000|Stroke|]"

DV_SCALE

"<scale_value>|<terminology_code>" |
"<scale_value>|<terminology_term>"

"1.5|[snomed_ct::127840596|minor difficulty|]"

DV_QUANTITY

"<value>,<unit>"

"78.500,kg"

DV_PROPORTION

"<numerator>/<denominator>;<proportion_kind>" where is <proportion_kind> is RATIO | UNITARY | PERCENT | FRACTION | INTEGER_FRACTION

"25.3/100;PERCENT"

DV_MULTIMEDIA

Standard JSON structure with compressed items internally

 
{
    "integrityCheckAlgorithm": "[openehr_integrity_check_algorithms::SHA-1]",
    "mediaType": "IANA_media-types::text/plain",
    "compressionAlgorithm": "[openehr_compression_algorithms::other]",
    "uri": "file://test.ethercis.com/dir/file.jpg"
}

DV_PARSABLE

CHECK

CHECK

DV_IDENTIFIER

Standard JSON

 
{
    "id": "id1",
    "issuer": "issuer1",
    "assigner": "assigner1",
    "type": "PERSON"
}

DV_INTERVAL<T:DV_ORDERED>

CHECK

CHECK

EhrScape Variants

EhrScape variants exist for the following DV_ types.

Formal type EhrScape Format

DV_PARSABLE

 
{
    "|value": "Hello world!",
    "|formalism": "text/plain"
}

DV_MULTIMEDIA

 
{
    "|integrityCheckAlgorithm": "[openehr_integrity_check_algorithms::SHA-1]",
    "|mediaType": "IANA_media-types::text/plain",
    "|compressionAlgorithm": "[openehr_compression_algorithms::other]",
    "|uri": "file://test.ethercis.com/dir/file.jpg"
}

DV_IDENTIFIER

 
{
    "|id": "id1",
    "|issuer": "issuer1",
    "|assigner": "assigner1",
    "|type": "PERSON"
}