This is the ValueSet that contains all the codes in BeVSVaccinationReasonCode (https://www.ehealth.fgov.be/standards/fhir/vaccination/ValueSet/be-vs-vaccination-reason-code) and BeVSVaccinationReasonCode (https://www.ehealth.fgov.be/standards/fhir/vaccination/ValueSet/be-vs-vaccination-reason-code). E.g. what you have to deal with if you get resources containing codes in either of them