SDR/MDR

TrialStack is both a metadata repository (MDR) and a Study Definitions Repository (SDR). It brings reusable metadata, trial authoring and versioned trial definitions into the same platform.

The MDR role manages reusable definitions and standards metadata. The SDR role manages the structured definition of each trial and its versions. Together, they connect the content an organization reuses with the decisions made for a particular trial.

Reusable metadata and a particular trial

An organization may already maintain standard assessments, form definitions and document templates. Those assets help teams reuse established content when they design a new trial.

The trial definition records the choices made for that trial. In our example, a reusable assessment is selected and scheduled at baseline and Week 12. The assessment’s definition and its trial-specific timing have related but different roles.

Reusable metadata	Trial-specific definition
A definition of the assessment	The assessment selected for this trial
A reusable collection form	The form version placed at the planned visits
A protocol template	The protocol content for this trial version

In TrialStack, teams select reusable metadata while authoring the trial. The resulting trial definition retains the selected content and its version context. These are complementary responsibilities within one system.

Both roles in one platform

DDF architecture allows the repository role to be integrated with authoring and metadata management. TrialStack combines these responsibilities with the preparation of documents and specifications.

%%{init: {"flowchart": {"nodeSpacing": 20, "rankSpacing": 24, "padding": 12, "subGraphTitleMargin": {"top": 8, "bottom": 20}}}}%%
flowchart TD
    subgraph TrialStack["TrialStack"]
        MDR["MDR<br/>Reusable metadata"] -->|select and reuse| Authoring["Trial authoring<br/>and review"]
        Authoring -->|create a version| SDR["SDR<br/>Versioned trial definitions"]
        SDR -->|prepare| Specifications["Protocol content<br/>Collection and analysis specifications"]
    end
    Specifications -->|versioned handoffs| Systems["Receiving systems"]

The diagram shows how the responsibilities connect. Reusable definitions inform trial authoring. The versioned trial definition then provides the basis for preparing protocol content, collection definitions and analysis specifications.

Those outputs remain connected to their trial context. Receiving systems use the relevant handoff packages for their own configuration, dataset builds or statistical execution.

An organization’s existing repositories and templates can also supply content to this workflow. TrialStack provides both repository roles alongside the tools for preparing the trial’s artefacts.

Make the version clear

Suppose the assessment moves from Week 12 to Week 16. The team needs to know which trial version contains the change and which outputs were prepared from the earlier version.

The same principle applies when a reusable assessment or form is updated. A later library version needs an explicit adoption decision for an existing trial. Keeping the selected versions identifiable gives reviewers a basis for assessing the consequences.

A repository’s name alone does not establish interoperability. Applications need compatible USDM content and interfaces. They also need agreement on the meaning of the values exchanged. Controlled Terminology explains that next layer.