In the current issue (3.11) of the EHR reference model, we have documented the concept "contribution" as being that collection of TRANSACTIONs corresponding to a single clinical session. That is to say, due to a patient contact, there could be the following new TRANSACTIONs:
- patient contact (this causes a new VERSIONED_TRANSACTION) - update to family history transaction (new version in existing VERSIONED_TRANSACTION) - update to current medications (new version in existing VERSIONED_TRANSACTION) - update to plan (new version in existing VERSIONED_TRANSACTION) - etc So the contribution in this case would be four TRANSACTIONs, each in distinct VERSIONED_TRANSACTIONs, and each having identical details in the CLINICAL_CONTEXT object. Now... contributions are the unit of change of the record. The question is, do we need to be able to easily find them after the fact, or is it not really important. If it is not important most of the time, then we can do nothing, sicne they will in fact be findable by looking for those TRANSACTIONs which have the right CLINICAL_CONTEXT objects. However, this will be slow, as it means going through all transactions in the entire record. If it is important to be able find contributions quickly (as I have theorised in the past, and Andrew Goodchild at the DSTC suggests), then we need to formalise the concept. Andrew has also suggested that EHR extracts are really a kind of "contribution", since they are effectively a bag of TRANSACTIONs to be applied to en EHR. While the TRANSACTIONs in the EHR_EXTRACT are not due to the same clinical session (they could be anything, depending on what the requestor asked for), their addition to the receiving EHR will in fact be a contribution. If we are to formalise this concept, we need to have use cases showing when/why contributions need to be handled as explicit entities. If we can prove the need, the following architectural possibilities suggest themselves: - use FOLDERs to act as contributions, i.e. every time a contribution goes in, make a new FOLDER that contains the references to those TRANSACTIONs - define CONTRIBUTION as a new subtype of FOLDER and use it as above - if we consider a contribution to be the equivalent of an outer transaction in a nested transaction, then we might create a new TRANSACTION for each controbution, whose contents are links to the other transactions in the contribution, - we could always add links to the first TRANSACTION in a contribution pointing to the other TRANSACTIONs in the group. thoughts? - thomas beale - If you have any questions about using this list, please send a message to d.lloyd at openehr.org
