Architecture, Governance and Migration
of Clinical Data.
Over 30 years of experience processing and analyzing structured and unstructured clinical data. Specialized in interoperability, semantic integrity and sustainable data architectures — grounded in our own formal research (AION · SILD).
Inspection at
Data-boundaries
Clinical data loses meaning in transfer.
Systematically. And mostly unnoticed.
When a clinical finding is transferred from a hospital information system to a FHIR server, information is lost. Not always. But systematically — and nobody notices. SILD analyzes against the mathematical model FM-4 and detects four canonical loss patterns — provably complete: every lossy transfer falls into exactly one of them. The result: formally verifiable audit findings.
4 canonical loss patterns SILD detects:
ORC → basedOn)08:12–11:47 → 00:00–23:59 (all-day)V/A/Z/G)Three disciplines, one methodology.
Wherever data moves between systems, losses occur — semantic, structural, operational. Our three service areas address exactly these transitions: from FHIR profile to platform migration, always with the claim of formal verifiability instead of informal best practice.
FHIR Governance & Semantic Integrity
Profiles, terminologies and mappings reliably maintained after go-live. This is not an implementation task — it is an operational discipline. "Go-live is a project. Operations is a discipline."
Clinical Data Architecture & Migration
Consolidate heterogeneous subsystems — based on our own CDV methodology (Clinical Data View) and three decades of database experience across eight systems. Hands-on, testable, documented.
Platform & Infrastructure
Scalable storage, compute and DevOps architectures for clinical and industrial applications — from ZFS NAS to object cloud, from PostgreSQL tuning to end-to-end DevOps pipelines.
We measure the loss of meaning in your FHIR operations.
Once your FHIR server is productive and the first API call succeeded, the real discipline begins: ensuring clinical meaning is preserved in every transfer. The SILD Audit delivers a quantified, reproducible inventory — against the mathematical FM-4 model, formally verified with Z3.
Analysis
We examine your productive FHIR exports against the FM-4 model and identify occurrences of the four canonical loss patterns — Type Narrowing, Temporal Collapse, Attribute Dropping, Reference Severing.
Report
Quantified loss of meaning per pattern and severity — with concrete examples from your data. Reproducible audit protocol that becomes measurable on re-audit.
Recommendations
Concrete profile adjustments, mapping corrections and governance responsibilities — no generic best practices, but prioritized measures per identified finding.
AION & CAIRN — the formal grounding.
SILD is not a workaround — it's mathematics. The formal foundations — Allen relations, DAG-based type hierarchies, causal inference, ε-differential privacy — are published as their own scientific ecosystem: AION as the formal model, CAIRN as the Python reference implementation. Open Source under AGPL-3.0, published on Zenodo, available on PyPI.
AION
Formal-mathematical operating system for clinical data. 13 Allen relations, DAG-based type hierarchy (Z3-verified), causal inference, explainable AI, ε-differential privacy.
aion-clinical.eu →CAIRN
Python reference implementation with bidirectional FHIR R4 mapping, HL7 v2 adapters, MLLP listener — and the SILD detector as integrated component. Current version aion-clinical 2.0.1.
ISCaD GmbH — Independent Software, Consulting and Development.
Clinical data architecture is a discipline — not an improvisation
Founded in 2000, based in Wedemark near Hannover, Germany. Specialized in architecture, governance and migration of clinical data — especially where the transition between systems becomes critical: FHIR profiling, semantic integrity, data migration.
Our own formal research in the AION / CAIRN / SILD ecosystem with five open-access publications on Zenodo. AGPL-3.0 open source. Commercial licenses on request.
- Founded
- 2000 · Wedemark, Lower Saxony, Germany
- Legal form
- GmbH · HRB 220407 · Local Court Hannover
- Management
- Friedhelm Matten
CV on LinkedIn → - Focus areas
- Clinical data · FHIR / HL7 / DICOM · Interoperability · Migration · Platform architecture
- Research
- AION · CAIRN · SILD · 5 papers on Zenodo
- License
- AGPL-3.0 · Commercial on request
What we have built.
A selection of mandates that show methodology and depth of work. The order follows substantive focus, not chronology.
Clinical Information & Analytics System
Web-based analytics system for clinical data at Hannover Medical School. Integration of patient, surgical, heart-lung machine, DICOM and laboratory data via HL7 interfaces. Real-time data as ADT/ORU messages, continuous integration of historical legacy data.
HL7 Integration & Quality Assurance
Clinical data integration from HIS, HL7, iMedOne, heart-lung machine and legacy systems. Patient-level data streams supporting national and international quality assurance procedures in pediatric cardiology and pediatric cardiac surgery. Web application for automated QA data entry control and manual correction after release.
Clinical Data View (CDV)
Development of a data structure for managing and analyzing complex structured and unstructured clinical data. Migration tool for consolidating data stocks from subsystems with heterogeneous database structures and types into CDV — the methodological foundation of many of our mandates.
ZFS Server System / SOPHOS Firewall
Construction of a ZFS-based server system with distributed replication. Samba server with ACLs for mixed client environments (MacOS / Windows / Linux). SOPHOS firewall as network perimeter with segmented zones for operations, administration and backup. Subsequent migration of data to object storage (MinIO with S3 interface) and development of analytics and administration tools for ongoing operations.
Backend Platform & DB Optimization
Integration of kitchens and online order / delivery processes (Uber, Wolt, Lieferando). PostgreSQL performance tuning, DevOps setup (GitLab, WireGuard), stabilization of production-grade operational structures. Extensive Python development on the backend.
HealthSafe24 — CIO & Shareholder
Responsibility for technology and architecture at HealthSafe24 GmbH as Chief Information Officer and co-shareholder. Subsequently external advisory role for strategic and technical development.
A selection of past mandates.
Grouped by domain. A deliberately restrained selection from three decades — not all projects are listed here, some are under confidentiality agreements.
Healthcare · Science
- Medizinische Hochschule Hannover
- Herzzentrum Leipzig
- Herz- und Diabeteszentrum NRW
- HealthSafe24 GmbH
Public sector · Education
- Region Hannover
- Deutscher Industrie- und Handelskammertag
- Niedersächsisches Studieninstitut
- Technologie-Zentrum Hannover GmbH
Business · Industry
- Informix Deutschland GmbH
- Deutsche Telekom AG
- T Systems
- EXPO 2000 GmbH
- Cash Cow Farmers GmbH
- Cloudeatery GmbH
- Yobst GmbH
- Nicolai Sanitätshäuser
What we think and write.
Observations from practice — mainly on the gap between FHIR go-live and sustainable data integrity. Condensations from mandates, mirrored against formal methodology.
Go-live is a project. Operations is a discipline.
Many hospitals are rolling out FHIR. But the actual test doesn't start with the first successful API call. It starts six months later — when it shows whether profiles, terminologies and mappings are actually maintained, or stranded in the no-man's-land between IT, clinical departments and architecture.
Read full article →Profiles as contracts.
A FHIR profile is not a technical document — it's a contract between source and target system. What the contract doesn't fix gets lost in the first mapping. On the anatomy of good profiles and why "validated" isn't enough.
Read full article →Semantic erosion without error messages.
When clinical data loses meaning, there is rarely a stack trace. The four canonical loss patterns — Type Narrowing, Temporal Collapse, Attribute Dropping, Reference Severing — and how SILD detects them formally.
Read full article →Ready for a conversation?
Whether SILD Audit, FHIR profiling, platform migration or a sparring session on your data architecture — we respond within 48 hours.
Discovery call (30 min)
No commitment. We understand your use case, check fit and honestly say whether we are the right partner.
SILD Audit or PoC (2–6 weeks)
Concrete use case on real data, demonstrated end-to-end. Clear go/no-go criterion before any next step.
Engagement or ongoing advisory (3–12 months)
Productive implementation with real data flow. Or: ongoing support for defined processes as a reliable extension of your team.