Ensuring Data Quality in Interoperable Health Systems: Validation and ICD-11 Postcoordination in Practice

Ensuring Data Quality in Interoperable Health Systems: Validation and ICD-11 Postcoordination in Practice

Interoperability is often presented as the ultimate goal in digital health systems. However, the ability to exchange data is only part of the challenge. The more difficult and often overlooked question is:

How do we ensure that the data being exchanged is actually correct?

Without proper validation, interoperable systems can quickly become pipelines for inconsistent, incomplete, or clinically invalid data.


Interoperability Without Validation: A Hidden Risk

Modern health systems increasingly rely on standards such as FHIR to enable data exchange between applications. While this ensures structural compatibility, it does not guarantee that:

  • The data is clinically valid
  • Codes are used correctly
  • Complex clinical concepts are represented accurately

In large-scale national systems, even small inconsistencies can propagate rapidly, leading to:

  • Poor data quality
  • Misinterpretation of clinical information
  • Reduced trust in digital systems

Validation as a Core Architectural Layer

To address this, validation must be treated not as an afterthought, but as a core architectural boundary.

A robust validation approach typically operates across multiple layers:

1. Structural Validation

Ensures that incoming data conforms to defined data models and profiles.

  • Correct resource types
  • Required fields present
  • Proper formatting of data

2. Terminology Validation

Ensures that all clinical codes belong to approved and standardized code systems.

  • Diagnoses aligned with ICD-11
  • Observations aligned with LOINC
  • Medicines aligned with national drug standards

This prevents:

  • use of invalid codes
  • inconsistent terminology across systems

3. Logical and Clinical Validation

This is the most complex layer.

It ensures that:

  • combinations of codes make clinical sense
  • relationships between data elements are valid
  • advanced representations are used correctly

The Complexity of ICD-11 Postcoordination

ICD-11 introduces a powerful concept known as postcoordination, where multiple codes can be combined to represent detailed clinical conditions.

For example:

  • A base diagnosis can be extended with additional qualifiers
  • Severity, location, or cause can be explicitly encoded

This allows for:

  • richer clinical representation
  • more precise data capture

However, it also introduces new challenges:

  • Not all combinations are valid
  • Incorrect combinations can distort clinical meaning
  • Systems must understand how to interpret and validate these expressions

Why Postcoordination Requires Special Handling

Unlike traditional classification systems, ICD-11 postcoordination is not simply about selecting a single code.

It requires:

  • understanding relationships between codes
  • validating allowed combinations
  • ensuring compliance with defined rules

Without proper validation:

  • different systems may interpret the same data differently
  • invalid clinical expressions may enter the system
  • interoperability becomes unreliable

A Practical Approach to Validation

In a national-scale system, validation must be enforced consistently across all participating applications.

This involves:

  • validating data before it is accepted into central systems
  • rejecting or flagging invalid submissions
  • guiding implementers toward correct usage

Rather than relying on individual systems to ensure correctness, validation is centralized as part of the interoperability layer.

This creates a clear boundary:

Only validated data becomes part of the national health record.


Impact on Data Quality and Governance

A strong validation layer directly improves:

Data Quality

  • Reduces errors at the point of entry
  • Prevents propagation of invalid data
  • Maintains consistency across systems

Interoperability Reliability

  • Ensures that exchanged data has consistent meaning
  • Reduces ambiguity between systems
  • Enables accurate interpretation

Governance and Trust

  • Establishes enforceable standards
  • Improves confidence in national data systems
  • Supports policy and decision-making

Why This Matters at Scale

At small scale, data inconsistencies can be manually corrected. At national scale, this is no longer possible.

Validation becomes essential to:

  • maintain integrity of large datasets
  • enable meaningful analytics
  • support AI and decision support systems

Without it, interoperability risks becoming:

a system that connects data, but cannot trust it.


Conclusion

Interoperability is a necessary foundation for digital health systems, but it is not sufficient on its own.

Ensuring data quality requires:

  • multi-layer validation
  • consistent terminology enforcement
  • careful handling of advanced clinical representations such as ICD-11 postcoordination

By treating validation as a core architectural component rather than an optional feature, health systems can ensure that:

  • data is not only exchangeable
  • but also accurate, meaningful, and reliable

This distinction is critical for building digital health systems that can be trusted at scale.