A long-term limitation of the openEHR demographic model has been the ability to clearly represent employment and similar relationships, which are commonly needed in healthcare (and are in the FHIR Admin model for example).
A proposal to do this is shown below. It adds the ACCOUNTABILITY concept to the model, which represents a defined requirement or need to be filled for one PARTY by another PARTY, usually playing a ROLE. The most common ACCOUNTABILITY is an employment ‘post’ or ‘position’ of an ORGANISATION, but a PERSON might have an ACCOUNTABILITY as well, like ‘personal trainer’.
Accountabilities are defined by an ACTOR (which in the openEHR model is a real entity, not a kind of role). If the Accountability is currently filled - e.g. if ‘Senior obstetric consultant’ job post is filled, then there will be a PARTY_RELATIONSHIP between the owner of the Accountability (an Organisation) and the filler, which will be another ACTOR (a PERSON) who has Capabilities including being an MD (and usually further qualifications in the Obstetrics area) playing the ROLE of Obstetric consultant in that relationship. The PARTY_RELATIONSHIP represents the employment relationship, and will be scoped by the ACCOUNTABILITY of that particular position (i.e. Senior obstetric consultant).
A modified form of the existing demographic model is shown below to achieve the above, with the modifications highlighted (note that this model is a copy of the original and class names have been changed so as not to clash with the original, i.e. ACTOR2 etc).
There are variations in how this could be modelled of course. THe form above enables unfilled Accountabilities such as job posts to be defined against an Actor (usually an Organisation), but for use in many situations, it may be that only those Accountabilities that are actually filled are needed to be represented. In that case, the Actor.accountabilities relationship would not be needed, and Accountability instances would only be attached to the Party_relationship representing their filling; when such relationships were severed (person leaves a job), the Accountability would disappear as well. The model above can be used in both ways.