Existing Wording: questionnaireanswers-sdc-structureddatacaptureanswers.html

questionnaireanswers-sdc-structureddatacaptureanswers.profile.xml

Element name: QuestionnaireAnswers.group.question.answer.value[x]

cardinality: 0..*

Proposed Wording: Element name: QuestionnaireAnswers.group.question.answer.value[x]

cardinality: 0..1

Comment:

Element in SDC Profile overrides the base resource with cardinality 0..* from 0..1. If cardinality max=1 is specified in base resource then derived profile can't make it many so the change is not compatible.

If it says you can only have 1 in the base resource, declaring '' in a profile would be breaking the maxOccurs rule of the base resource. If SDC require 0.. then must recommend cardinality change be made to the base resource.

FHIR DSTU2 in section 2.1.0.4 states that "Profiles cannot break the rules established in the base specification".

It is implied but not explicitly spelled out in the FHIR spec but is spelled out here. See: http://fhirblog.com/2014/03/26/fhir-profiles-an-overview/

Note there is separate ballot issue comment for FHIR DSTU2 spec to fully define cardinality overrides that are not allowed and add validation checks to the publishing tools to catch such errors.