Healthcare Interoperability: Breaking Down Information Silos to Improve Care

Your day at the pharmacy is winding down when a familiar patient arrives at the counter with her daughter. She hands you several annotated pages showing recent changes to her therapy. Between them, they piece together the events of the past few days: an ambulance ride, a hospital transfer, and a discharge shortly afterward.

You ask why she was hospitalized, and the answer is vague: “a bad flu, a weak heart, and worn-out lungs.” There is no discharge summary and no clear diagnosis in the documents provided. Her family physician does not even know she was hospitalized yet. Most likely, they will only find out once the summary sent by fax has been scanned into the electronic medical record.

If this scenario feels realistic and more than a little frustrating, that is because it is. Despite everyone’s best efforts, health information still struggles to move smoothly from one care setting to another.

That is what we call a lack of interoperability.

What is interoperability?

The IEEE defines interoperability as the ability of two or more systems to exchange information and use it. In healthcare, HIMSS adds an important dimension: that exchange must happen across organizations and help improve care delivery.

In other words, connectivity alone is not enough. Data must not only move between systems, it must also be understood, interpreted correctly, and translated into meaningful clinical action.

The four layers of healthcare interoperability

For health data exchange to truly support care, it needs to rest on several complementary layers.

1. The foundational layer: moving information

This is the technical backbone of data exchange. It is the channel through which information travels. Between two systems, this includes standardized interfaces such as REST APIs.

Without this layer, nothing moves.

2. The structural layer: shaping the message

Data also needs to be organized in a format systems can understand. This layer deals with the structure of the data itself. Standards such as HL7 FHIR play a central role here by defining how clinical information should be formatted for different use cases.

Without a clear structure, information may circulate, but it cannot be meaningfully used.

3. The semantic layer: making sure everyone means the same thing

Clinical information must be interpreted consistently and without ambiguity. This is where standardized terminologies such as SNOMED CT, ICD-10, and LOINC come in, assigning precise codes to specific clinical concepts. In Canada, national editions of these terminologies are maintained by Canada Health Infoway and the Canadian Institute for Health Information (CIHI).

Without shared semantics, we are simply moving unclear data faster.

4. The organizational layer: governing exchange

Interoperability also depends on rules. Who is allowed to send what information, to whom, with what consent, and under what security, access, and accountability requirements?

These questions fall under data governance.

Without that framework, even the right information can end up in the wrong place at the wrong time.

Medication information: why a common language matters

The opening scenario makes this especially clear: prescriptions, discharge summaries, and medication profiles all need to move from one system to another. For that to happen, organizations need a shared language. That means making two key choices: the exchange standard, which is the container, and the terminology, which is the content.

HL7 FHIR has emerged as the modern exchange standard for sharing clinical data.

From a terminology standpoint, Canada relies on the Canadian Clinical Drug Data Set (CCDD), which assigns unique codes to clinical drugs and certain medical devices.

That coding supports understanding across systems, but it does not address every operational need across the healthcare network. Pharmacies, clinics, and hospitals often depend on more detailed internal terminologies to support their workflows. As a result, mappings are needed to translate one terminology into another.

That is where Vigilance’s database comes in. Used by a broad range of healthcare professionals, it helps create those mappings and bridge the gap between terminologies.

Points of breakdown: risks along the patient journey

When interoperability is lacking, as in our opening example, the risks are anything but theoretical.

Transitions of care, such as admission, discharge, or transfer, are critical points in a patient’s journey. Without timely access to information from another care setting, medication reconciliation becomes much harder to carry out thoroughly. Without a clear clinical picture, including diagnosis or relevant lab data, it also becomes more difficult to deliver the right care at the right time.

In community pharmacy, incomplete access to essential information such as documented allergies, recent lab results, or immunization status often forces clinicians to work with only part of the picture. Patients then end up, through no fault of their own, carrying part of the burden of communicating the information needed for their own care.

These situations are not unusual. They point instead to structural gaps that repeat themselves every day in thousands of pharmacies across the country.

Why do silos still exist?

If the solutions are out there, why does interoperability still lag behind?

Because this is about much more than technology.

Of course, the technical dimension remains a real barrier. Many legacy systems were designed in isolation. Modernizing them comes at a high cost in money, time, and human resources.

In some contexts, the lack of a universally recognized unique patient identifier adds another layer of difficulty. When two institutions do not use the same identifiers, it becomes harder to confirm that they are in fact treating the same person.

Even when data exists and is well structured, it is not always shareable. Security requirements, internal policies, and commercial considerations can all restrict access.

There are also regulatory barriers. Sometimes it is not the tools that are missing, but the legal framework that slows data exchange. When explicit consent is required, certain information may need to remain confined to a single system.

There is also the question of accountability. If inaccurate information flows between two care settings and causes harm, who is responsible? Until governance, trust, and liability issues are properly addressed, interoperability will remain incomplete.

Interoperability and medications: a semantic foundation built for Canada

In a healthcare environment where interoperability is essential, the choice of medication terminology becomes critical.

Yet many solutions used in Canada, such as First Databank or Oracle’s Multum, were originally built for the U.S. market. They are grounded in the NDC  code system and the FDA  regulatory framework. Canada, by contrast, relies on DINs and NPNs within a distinct regulatory environment. That difference matters. Making U.S.-designed solutions truly usable in Canada requires significant adaptation work upstream.

A terminology designed specifically for the Canadian context is therefore a major strategic advantage.

Vigilance Santé created RxST (Rx Standardized Terminology) using Canadian identifiers as its foundation from the outset. Aligned with the ISO’s international IDMP standard, RxST provides a detailed representation of health products used in Canada. Its content is bilingual, in both French and English, and is structured in a modern format inspired by FHIR.

More importantly, RxST helps organizations and healthcare professionals tackle medication interoperability challenges in a practical way. It does more than support the transmission of structured data. It ensures that medications are represented in a way that is fit for purpose.

By precisely identifying the molecule, dosage form, and strength, it becomes possible to automate alerts and support decision-making with far greater reliability. By identifying the manufacturer, format, and correct packaging level, dispensing and inventory management can also be optimized.

The challenge, then, goes beyond coding alone. It is about reducing ambiguity at the source.

How can we work toward greater interoperability, starting now?

This transformation depends heavily on decision-makers and software vendors, but it must also happen with pharmacists and other clinicians. Their contribution is essential to ensure that the right data moves in the right format and at the right time.

Clinical practice itself is a key lever. Every time information is entered into a patient record, there is an opportunity to make it more interoperable. Too often, however, systems lack the flexibility and granularity needed to support optimal data entry. A diagnosis, for example, may end up buried in a free-text note simply because no structured field exists for it.

When systems allow it, entering information in coded form or in designated fields helps unlock its full interoperability value.

So that information can finally follow the patient

Interoperability is not just a technology issue. It is a prerequisite for making sure clinical information is available where it is needed, when it is needed, and in a form that makes sense.

Can we really afford anything less?

The question is no longer whether systems should communicate. It is whether we are prepared, collectively, to do what it takes to make that happen and to expect more from our tools so that clinical data can finally follow the patient throughout the continuum of care.

And what about you? What is preventing you today from accessing the information you need to care for your patients effectively and with confidence?