MII IG PRO
2026.2.0 - ci-build Unknown region code '276'

MII IG PRO, published by Medizininformatik-Initiative. This guide is not an authorized publication; it is the continuous build for version 2026.2.0 built by the FHIR (HL7® FHIR® Standard) CI Build. This version is based on the current content of https://github.com/medizininformatik-initiative/kerndatensatzmodul-proms/ and changes regularly. See the Directory of published versions

Domains

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Overview of Health Domains

Health domains are fundamental constructs that represent different aspects of health and well-being. In the context of Patient-Reported Outcomes (PROs), domains enable the systematic capture and comparability of health states across different measurement instruments.

Related pages:

Definition and Significance

A health domain is a specific, theoretically grounded aspect of health that can be captured by various measurement instruments. The domain-based structuring of PROs offers several advantages:

  • Interoperability: Different questionnaires measuring the same construct become comparable
  • Flexibility: Institutions can choose the instrument that best fits their needs
  • Continuity: Comparability is maintained even when instruments are changed
  • Norming: Uniform reference values across instruments

PROMIS Framework: The 8+1 Core Domains

The MII PRO Module follows the PROMIS (Patient-Reported Outcomes Measurement Information System) framework, which defines 8 scientifically validated core domains. These domains form the conceptual foundation for systematic PRO capture and have been operationalized in the PROMIS-29 Profile v2.1:

  1. Physical Function – 4 items
  2. Anxiety – 4 items
  3. Depression – 4 items
  4. Fatigue – 4 items
  5. Sleep Disturbance – 4 items
  6. Ability to Participate in Social Roles and Activities – 4 items
  7. Pain Interference – 4 items
  8. Pain Intensity – 1 item

Additional important PROMIS domain in the MII PRO Module:

  1. Cognitive Function – captured by the PROMIS Cognitive Function 4a Short Form

These 9 domains represent the most important aspects of self-reported health and have been validated through extensive psychometric research. The PROMIS-29 instrument (29 items) captures the first 8 domains, while Cognitive Function is supplemented by separate Short Forms.

Comparable multi-domain instruments:

  • SF-36 (Short Form 36): 8 domains of health-related quality of life
  • WHOQOL-BREF: WHO instrument with 4 main domains (physical, psychological, social, environment)
  • EQ-5D: 5 dimensions (mobility, self-care, usual activities, pain, anxiety/depression)

Core Domains in the MII PRO Module

The implementation in the MII PRO Module follows the PROMIS structure and extends it with additional established instruments:

1. Depression Domain (PROMIS Core Domain)

Status: Fully implemented (2025) LOINC Code: 77861-3 "PROMIS Depression T-score" Supported instruments:

  • PHQ-9 (Patient Health Questionnaire-9) – Details
  • BDI-II (Beck Depression Inventory II) – Details
  • PROMIS Depression Short Forms – Details
  • HADS-D (Hospital Anxiety and Depression Scale - Depression)
  • EPDS (Edinburgh Postnatal Depression Scale)
  • CES-D (Center for Epidemiologic Studies Depression Scale)

Characteristics:

  • Captures symptoms of depressive mood, dejection, hopelessness
  • T-Score normalization (Mean=50, SD=10)
  • Population norms based on EHIS Wave 3 (n=287,530)
  • Validated cross-walking tables between instruments – see Mappings

2. Anxiety Domain (PROMIS Core Domain: Anxiety)

Status: Planned (2026) Planned instruments:

  • GAD-7 (Generalized Anxiety Disorder-7)
  • PROMIS Anxiety
  • HADS-A (Hospital Anxiety and Depression Scale - Anxiety)
  • BAI (Beck Anxiety Inventory)

Characteristics:

  • Captures worry, nervousness, tension, anxiousness
  • Differentiation between state and trait anxiety
  • Somatic vs. cognitive anxiety components

3. Physical Function (PROMIS Core Domain: Physical Function)

Status: Partially implemented (PROMIS-29, EQ-5D) Implemented instruments:

  • PROMIS Physical Function – Details
  • EQ-5D Mobility Dimension – Details
  • Planned: HAQ, WHODAS, SF-36 PF

Characteristics:

  • Mobility, self-care, everyday activities
  • Differentiation by severity of limitation
  • Age- and sex-specific norms
  • Item banking for adaptive measurement – see figure

4. Pain Domain (PROMIS Core Domains: Pain Interference and Pain Intensity)

Status: Partially implemented (PROMIS-29, EORTC) Components:

  • Pain Intensity: Numeric Rating Scale (0-10)
  • Pain Interference: Impact of pain on functioning
  • Pain Quality: Nature and characteristics of pain

Implemented instruments:

  • PROMIS Pain Intensity
  • PROMIS Pain Interference
  • EORTC QLQ-C30 Pain Scale – Details

5. Fatigue (PROMIS Core Domain: Fatigue)

Status: Partially implemented (PROMIS-29, EORTC) Instruments:

  • PROMIS Fatigue
  • EORTC QLQ-C30 Fatigue Scale
  • Planned: FSS, FACIT-F

Characteristics:

  • Physical and mental exhaustion
  • Impact on daily activities
  • Differentiation from depression

6. Sleep Disturbance (PROMIS Core Domain: Sleep Disturbance)

Status: Partially implemented (PROMIS-29) Instruments:

  • PROMIS Sleep Disturbance
  • Planned: PSQI, ISI

Characteristics:

  • Sleep quality, difficulty falling and staying asleep
  • Daytime sleepiness as a consequence
  • Circadian rhythm disturbances

7. Social Function (PROMIS Core Domain: Ability to Participate in Social Roles)

Status: Partially implemented (PROMIS-29, EORTC) Instruments:

  • PROMIS Ability to Participate in Social Roles
  • EORTC QLQ-C30 Social Functioning
  • Planned: SPS, F-SozU

Characteristics:

  • Social participation and role function
  • Quality of social relationships
  • Isolation and loneliness

8. Cognitive Function (PROMIS Cognitive Function 4a)

Status: In implementation (2025) Instruments:

  • PROMIS Cognitive Function 4a Short Form
  • EORTC QLQ-C30 Cognitive Functioning (already implemented)

Characteristics:

  • Concentration and memory
  • Cognitive clarity and mental acuity
  • Subjective cognitive abilities

Specialized Domains

Oncology-Specific Domains: EORTC QLQ-C30 Framework

​EORTC QLQ-C30 Domains

Figure 1: Conceptual model of the EORTC QLQ-C30 – From physiological variables to quality of life

The EORTC QLQ-C30 framework illustrates the relationship between different domain levels:

  • Physiological variables influence symptoms
  • Symptoms affect functioning
  • Functioning shapes health perception
  • All factors culminate in overall quality of life

Implemented through the EORTC QLQ-C30:

  • Nausea and vomiting
  • Appetite loss
  • Dyspnoea (shortness of breath)
  • Constipation
  • Diarrhoea
  • Financial difficulties due to illness

Details see EORTC QLQ-C30 in the PRO Library.

Quality of Life Domains

  • Global Quality of Life (EORTC, EQ-5D VAS)
  • Health-Related Quality of Life (EQ-5D Index)
  • Role Function (EORTC)
  • Emotional Function (EORTC)

Domain Hierarchy and Relationships

Health (overarching)
+-- Physical Health
|   +-- Physical Function
|   +-- Pain
|   +-- Fatigue
|   +-- Symptom Burden
+-- Mental Health
|   +-- Depression
|   +-- Anxiety
|   +-- Cognitive Function
|   +-- Emotional Well-Being
+-- Social Health
|   +-- Social Function
|   +-- Social Support
|   +-- Role Function
+-- Global Health
    +-- Quality of Life
    +-- General Health Status

Domain Alignment and Questionnaire Capabilities

The MII PRO Module defines the "domain-alignment" capability for each instrument:

* extension[questionnaire-capabilities].extension[domain-aligned].valueBoolean = true

This means that an instrument:

  1. Is unambiguously assigned to one or more domains
  2. Produces scores that can be mapped to domain T-Scores
  3. Is comparable with other instruments of the same domain

Details on the technical implementation see Questionnaire Capabilities.

Methodological Foundations

Item Response Theory (IRT)

Classical Test Theory (CTT)

  • Traditional method, used by PHQ-9, BDI-II
  • Sum scores with linear transformation
  • Simpler to implement, less precise

Cross-Walking and Harmonization

Practical Application of Domains

Clinical Decision Support

Domain-based thresholds for:

  • Screening: Identification of patients requiring treatment
  • Monitoring: Progress tracking and therapy adjustment
  • Outcome assessment: Treatment success and remission

Research and Care Quality

  • Meta-analyses: Pooling of studies with different instruments
  • Registry studies: Harmonized outcomes across sites
  • Quality indicators: Fair comparisons despite different assessments

Personalized Medicine

  • Precision medicine: Domain profiles for therapy selection
  • Adaptive care pathways: Domain-based algorithms
  • Patient-centered care: Focus on relevant domains

Implementation Notes

FHIR Resources per Domain

  1. ObservationDefinition: Defines domain score with reference ranges
  2. ConceptMap: Mapping from instrument scores to domain scores
  3. Observation: Instances of domain scores with provenance
  4. Library (CQL): Calculation logic for complex transformations

Best Practices

  • Always document the source instrument (derivedFrom)
  • Specify the mapping method (method)
  • Consider confidence intervals
  • Use population-specific norms

Future Developments

Short-Term (2025-2026)

  • Complete implementation of all PROMIS-29 domains
  • Cross-walking tables for PHQ-9 to PROMIS Depression
  • Validation studies for the German population

Medium-Term (2026-2027)

  • Item-based domain scores
  • Computer Adaptive Testing (CAT) integration
  • Extended domains (spirituality, resilience)

Long-Term (2027+)

  • AI-based domain prediction
  • Multimodal integration (PROs + biomarkers)
  • Real-time domain monitoring

Summary

The domain-based structuring of PROs in the MII Module enables a future-proof, flexible, and interoperable capture of health states. By consistently mapping different instruments onto shared domains, the vision of harmonized, patient-centered care becomes a reality. The depression domain already demonstrates the practical feasibility of this concept today, while additional domains will follow successively.

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