The Welsh Government’s 2023 mandate for using the Fast Healthcare Interoperability Resources (FHIR) standard across health and social care marks a crucial step in the nation’s interoperability plans.
Callum Saint, FHIR Standards Development and Implementation Service Owner at Digital Health and Care Wales (DHCW) and an HL7 UK Management Board member, shares his experiences unlocking the potential of connected data for patient care and service improvement.
Precision and the power of shared language
Callum brings an analytical chemistry background to his work, emphasising precision and consistency. Such qualities are vital for his work on digital health standards.
Take, for example, a clinical term such as ‘condition’. Each organisation can assign subtly different meanings and clinical codes to data fields, resulting in variation across systems that support a variety of care settings.
“You assume you’re on the same page, and you’re not. That’s the challenge with interoperability. Two systems say the same thing but have different interpretations,” says Callum.
Such semantic confusion can pose a significant risk to patient safety and lead to operational inefficiency.
FHIR addresses this by defining discrete, manageable resources with a common language that preserves the nuances of data. This ensures the intended meaning and context of a patient’s information are universally and unambiguously understood, reducing the risk of patient safety events and aiding coordinated care.
The National Data Resource: A native FHIR Core
Callum’s team manages and develops the FHIR Implementation Guide for NHS Wales. Their work is structured around Agile methodologies, including sprints, daily stand-ups, and planning sessions, all focused on the current release (version 2.6.0 at the time of writing – find their IG here).
Callum also participates in DHCW’s data modelling groups and runs FHIR-focused working groups, alongside his commitment to HL7 UK board meetings.
This work supports the ambitious “Once for Wales” principle, ensuring nationally agreed-upon data solutions can be applied consistently across all health boards.
At the strategic heart of this plan, the National Data Resource (NDR) is moving away from fragmented, local databases toward a unified platform.
The NDR aims to create a comprehensive, national platform that connects health and social care data and provides a foundation for patient-centred healthcare.
A crucial structural element of the NDR is the Care Data Repository (CDR), which processes FHIR messages and is built – quite uniquely – as a persistent FHIR store.
This commitment means FHIR is not just a temporary integration or translation layer. It is the fundamental, long-term structure of the data itself. Every clinical and administrative record within the CDR is a native FHIR resource, ensuring data remains future-proof, consistently structured, and readily accessible for clinical, research, and planning purposes.
As Callum states, “Getting data into a shared structure that’s used between systems is obviously very powerful, so that everybody can speak the same language. FHIR allows you to do this.”
This unified approach promotes the consistent, high-quality data flow essential for creating a truly complete and longitudinal patient record.
Early successes and data quality improvements
The journey to national implementation started with targeted, high-impact projects. The initial success was the implementation of electronic prescribing in secondary healthcare, which provided the crucial evidence base to secure the formal, national FHIR mandate.
Implementation has rapidly expanded since then to cover core foundational data sets, including:
- Administrative data: Profiling essential patient demographics, organisation, and location details.
- Allergy data: Developing structured and coded profiles for drug allergy records, ensuring instant, consistent safety information across Wales.
- Paediatric growth charts: These were among the first live, high-priority data structures fully implemented within the CDR, offering clinicians a consistent, national view of a child’s development.
Beyond exchange, FHIR is structured to improve data quality, as data modellers can define fields within a FHIR resource as mandatory, requiring systems to provide a minimum dataset.
“This approach ensures that all necessary data points are captured to provide comprehensive patient care. It can also significantly improve overall data completeness,” says Callum.
Opportunities ahead: Collaboration, clinical use cases and experimentation
Looking to the future, Callum sees a significant long-term opportunity in fostering UK-wide collaboration through bodies such as HL7 UK. He cites Australia’s Sparked initiative as an excellent model for a cohesive UK approach.
Callum identifies a further opportunity to leverage clinical data and evidence to strategically drive FHIR development, focusing on which FHIR resources or profiles will yield the greatest measurable benefits, such as a reduction in adverse outcomes.
However, he notes, FHIR’s relative novelty has led to some caution.
“People are a bit apprehensive about going into the FHIR ecosystem because it’s so new,” he says. “But once you dip your toe in, it’s not as bad as you think. You’re going to make mistakes; there’s no way around that. That’s fine; just make sure you’re learning from your mistakes and continually improving.”
Wales is leading the charge by using FHIR to enable greater data sharing. Callum welcomes the direction of travel.
“Siloing and hoarding data is unnecessary in this day and age. Data needs to be shared as much as possible, and as much as interoperable standards allow. As the Caldicott principles suggest, not sharing data can be as harmful as oversharing data. We have to ensure data sharing benefits the patient, and FHIR and other data standards can help us do this more quickly and more easily.”
By making FHIR the structural core of its National Data Resource and taking an interactive approach to its implementation, Wales is creating a blueprint for a patient-centred digital health future that can benefit the UK as a whole.
Image: Flag of Wales Author DirectX3