How we store and identify questions

[xamelon]

Description

Form DSL contains information about questions and visual items
Each question have unique id
Non-question visual items don't have ID
Question identifier must be convertible to FHIR Questionnaire linkId
Questions can be grouped
Question identifier should be stable between form updates
FHIR Questionnaire has linkId for this purpose. But word "link" is less meaningful, because "id" is already convey that semantics. Also there are less characters to type without "link"

Questions

Can we provide field identifier uniqueness?
Need to know order of questions on view

Aspects

• key uniqueness
• natural questions order on UI
• easy to write and understand

Approaches

• Store questions as map where key is an identifier and value is definition

{:temperature {...}
 :blood-pressure {...}}

• Store questions as an array with additional attribute "id"

[{:id "blood-pressure"}
 {:id "temperature"}]

• Store questions as array of pairs of key and definition

[:temperature {...}
 :blood-pressure {...}]

Decision matrix

[xamelon]

We can get rid of additional attribute by holding questions in a map where key is a question identifier and value is definition

LateVisitDocument
{:type aidbox.sdc/form
 :questions {:basic-question {:label "Super basic question"}}}

Pros:

• we don't need additional attribute
• map semantics checks key uniqueness

Cons:

• map is unordered and we should handle order manually
• unnatural to write for non-programmers

[xamelon]

Additional attribute called id. Questions stored as list (like in Questionnaire)

LateVisitDocument
{:type aidbox.sdc/form
 :questions [{:label "Super basic question"
              :id :basic-question}]}

Pros:

• shorter than linkId
• questions order is clear

Cons:

• can't guarantee uniqueness (we should handle it manually)

[niquola]

id is good because it is aligned with Questionnaire and natural in extraction

[rublag]

Can there be multiple question with the same label?

[qdzo]

Questionnaire and QuestionnaireResponse share linkId attribute.

link prefix in linkId conveys that these ids are related in some way.
If we remove link prefix - in questionnaire we assume that this is questions id, but
in questionnaireResponse we are able to think that is an answer Id - but that's not true.

Also repeated answers should share the same linkId
and if we name that attribute just id - it will confuse us.

I think it's better to leave linkId or make more meaningful name - like questionID (or in short form qid)

[xamelon]

Also we can get rid of attribute by combining previous two solutions. Store ids and questions as pairs in a list

LateVisitDocument
{:type aidbox.sdc/form
 :questions [:basic-question {:label "Super basic question"}
             :second-question {:label "Super basic question"}]}

Pros:

• we don't need additional attribute
• we preserve order

Cons:

• can't guarantee uniqueness (we should handle it manually)
• looks unnatural for all users