See Questionnaire for introduction and use of the resources and its elements.
Creating and Maintaining Questionnaire
Questionnaire are created and updated through Questionnaire Create and Questionnaire Update, respectively.
Later finding appropriate Questionnaire resources depends on the quality and granularity with which the Questionnaire elements are populated when created/updated. Consequently, effort should be made to ensure these elements are populated.
Filtering applied on finding appropriate Questionnaire could involve the following elements of Questionnaire:
useContextehealth-intendedAudienceehealth-recommendationstatusjuristiction
Possibly, the following elements (and others) could be used as well:
titledescriptionversionpublisheridentifier
Preparing a Questionnaire for Infrastructure Rule Use
The description here applies for Questionnaire resources where processing of corresponding QuestionnaireResponse involves extraction of answer(s) to certain questions in the Questionnaire.
In the eHealth Infrastructure, such processing is performed through rules captured in Library resources. In order to make the rules robust and allow for change of question order and additional questions and answer options, the Questionnaire shall utilize defined questions in the form of DefinedQuestion resources. See DefinedQuestion for further details.
When a question in Questionnaire.item is eligible for extraction in a rule, a DefinedQuestion shall be either found or created and subsequently referenced in Questionnaire.item.definition.
The Questionnaire.item.definition shall be a business versioned reference on the form url|(business) version.
An example:
As noted in DefinedQuestion, despite any reference through Questionnaire.item.definition and the values the DefinedQuestion may have, it is the answer list and other values of the Questionnaire.item that take precedence.
Preparing a Questionnaire with Embedded, Simple Calculations
A Questionnaire defined with the eHealth profile ehealth-questionnaire-advanced (see https://docs.ehealth.sundhed.dk/latest-released/ig/StructureDefinition-ehealth-questionnaire-advanced.html) can contain zero, one or more expressions performing a calculation based on answers to questions in the Questionnaire. The expression can make use of zero, one or more variables which identify the particular question/answers more concisely.
A Questionnaire defined with eHealth profile ehealth-questionnaire (see https://docs.ehealth.sundhed.dk/latest-released/ig/StructureDefinition-ehealth-questionnaire.html) cannot contain expressions nor variables.
Defining a Variable
A variable intended for use in an expression (see below) is defined using the extension variable. An example of a variable is shown below as an excerpt of a Questionnaire (in profile ehealth-questionnaire-advanced) in JSON:
{
"url": "http://hl7.org/fhir/StructureDefinition/variable",
"valueExpression": {
"name": "Count",
"language": "text/fhirpath",
"expression": "QuestionnaireResponse.repeat(item).where(linkId='1.2.208.176.1.5.1,7a481674-9016-46bb-8dd8-2ee49f5bbd53,Sundhedsdatastyrelsen').answer.valueInteger"
}
}
The variable here is defined at Questionnaire root level referencing a particular question through its Questionnaire.item.linkId. On evaluation in a QuestionnaireResponse, the variable will hold the integer value of the answer (presumably, the referenced Questionnaire.item has integer answer type).
A variable is supported for a question with answer type choice, integer and decimal provided that:
the question is not a calculated expression
a question of type choice is single-choice only
all answer options for question of type choice have an ordinalValue (see ordinalValue)
An example of a variable evaluating to an ordinal value is shown below as an excerpt of a Questionnaire (in profile ehealth-questionnaire-advanced) in JSON:
{
"url": "http://hl7.org/fhir/StructureDefinition/variable",
"valueExpression": {
"name": "BreathingDifficulty",
"language": "text/fhirpath",
"expression": "iif(QuestionnaireResponse.repeat(item).where(linkId='1.2.208.176.1.5.1,6e6bb131-debd-4675-803b-7d783a75acc6,Sundhedsdatastyrelsen').answer.valueString = 'Severe', 2,
iif(QuestionnaireResponse.repeat(item).where(linkId='1.2.208.176.1.5.1,6e6bb131-debd-4675-803b-7d783a75acc6,Sundhedsdatastyrelsen').answer.valueString = 'Normal', 1, {}))"
}
}
The expression above relies on the definer to ensure consistency between the actual answer values (in Questionnaire.item.answerOption.value[x]) and ordinal values possibly assigned in Questionnaire.item.answerOption.ordinalValue.
Defining a Calculation Expression
An expression is defined in a separate Questionnaire.item (or recursively, Questionnaire.item.item) which shall have:
Questionnaire.item.readOnlyset totrueQuestionnaire.item.typeset todecimal
The expression itself is defined in the extension sdc-questionnaire-calculatedExpression (see calculatedExpression) which is an Expression FHIR element type containing:
language- the expression language. The supported language is a subset of FHIRPath described below. The expression language is specified as"text/fhirpath".expression- the expression
An example calculation expression is shown below as an excerpt of a Questionnaire (in profile ehealth-questionnaire-advanced) in JSON:
"extension": [
{
"url": "http://hl7.org/fhir/uv/sdc/StructureDefinition/sdc-questionnaire-calculatedExpression",
"valueExpression": {
"language": "text/fhirpath",
"expression": "%Animal * %Count"
}
},
"linkId": "1.2.208.176.1.5.1,25d40dde-f91c-4f11-9477-c6cca71d4178,Sundhedsdatastyrelsen",
"text": "Total",
"type": "decimal",
"required": false,
"readOnly": true
}
The following runtime behavior is not performed when maintaining the Questionnaire but provides background. On evaluation in a QuestionnaireResponse, the QuestionnaireResponse.item corresponding to the Questionnaire.item above shall contain the calculated value in its QuestionnaireResponse.item.answer.valueDecimal. Provided that values are available in the variables Count and Animal (in the evaluation context of the QuestionnaireResponse), the calculated result can be determined.
In case the expression is defined using one or more Questionnaire.item that are not guaranteed to be present in a well-formed QuestionnaireResponse, it should be defined as not required.
A Questionnaire.item is not guaranteed to be present when either:
it is not required
it depends on other answer(s) (with
Questionnaire.item.enableWhen)it is placed in a group nesting structure which has
enableWhenitself
Expression Language
The supported expression language is the following subset of FHIRPath:
Arithmetic: multiplication, division, addition & subtraction only
Parentheses ‘
(' and ')'Constants
The equals operation (
=) for primitive typesThe iif function
Releasing a Questionnaire
Once a Questionnaire has been finalized it is eligible for use in PlanDefinition/ActivityDefinition telemedicine packages. Finalizing is performed by setting the Questionnaire status to value active through a Questionnaire Update.
The Questionnaire cannot be changed once having status set to active, except for retiring it by changing status to retired.
Retiring a Questionnaire
Retire a Questionnaire by setting the Questionnaire status to value retired through a Questionnaire Update.
Retiring a Questionnaire does not impact current or past use in resources referencing it. It signals that further use in new PlanDefinition/ActivityDefinition telemedicine packages should not happen.
Managing Defined Questions/Answers
See DefinedQuestion for introduction and use of the resource and its elements.
A DefinedQuestion serves multiple purposes:
Allows for establishing a versioned set of reusable questions, possibly with answer lists, that can be copied when defining Questionnaire resources.
Enables robust identification of a question in a Questionnaire. By adding the DefinedQuestion elements
urlandversionwith a pipe as separator to a particular question throughQuestionnaire.item.definitionas described above, a rule can process a QuestionnaireResponse to the Questionnaire and reliably identify the answer to that question. The QuestionnaireResponse already uses thelinkIdfrom theQuestionnaire.item.linkIdto identify the particular question, but by traversing this link and doing lookup on anyQuestionnaire.item.definition, a rule can work irrespective of linkId values.