Using IPS as a reference model for healthcare systems.

The IPS is designed to be a cross-border summary. Because of this, it has good enabling features and a consensus-based baseline of resources and terminologies. It is a reference specification for continuity of care in cross-border settings. Understanding the nature of IPS is important to evaluate its advantages and where it is not applicable:

IPS uses (for example) MedicationStatement for containing a patient’s “medication lists”. This is a helpful specification - instead of debating which resources to use, implementers can take the choices that are compatible with the IPS.

IPS uses SNOMED GPS. For cross-border use cases, this is great - a common, even if reduced, set of SNOMED values. For medications, ATC is also supported. While ATC is not sufficient to identify a product, it provides a common enough classification.

This also means that the PS has limitations - not because of its implementation, but because of its purpose. The IPS imposes a format (it is a static document with deliberately limited information) and some constraints that are adequate for cross-border, which normally may be insufficient for healthcare records and data exchange in a RESTful way.

Patient.name is mandatory

In the FHIR IPS specification, Patient name is mandatory. This is adequate for a continuity of care, where the patient identification is important and the name is expected there. However, some uses of the Patient resource - outside of a continuity-of-care document, may not require Patient name, or may even require it to be empty.

Logical references are not supported

Some IPS resources actually exclude the use of logical references for Patients. This is deliberate (IPS is a document, and all the resources are available in the document, so they can be referenced to literally, and there’s no need for logical references). In real-life RESTful operations, in some cases there is no need to exchange the Patient resource and exchanging a logical identifier is important.

Using ATC (and other international codes) for medications

ATC classification and even SNOMED codes have been confirmed to be insufficient to cover the full range of medications in prescriptions and dispenses. Those high-level codes are OK for now (while alternatives are being developed) and for cross-border. For EHRs and for intra-border communication, there are national drug catalogs and terminologies.

IPS contains only a part of the FHIR resources

IPS contains a few dozen resources. FHIR contains 150 and this number is growing. Limiting to a subset of resources means removing the support to certain data. For example details about scheduling, dispensing, workflows, etc., all of which may be important for patient safety.