Epidemiology

DDI (Data Documentation Initiative)

A widely used, international standard for describing data from the social, behavioral, and economic sciences. Two versions of the standard are currently maintained in parallel:

  • DDI Codebook (or DDI version 2) is the simpler of the two, and intended for documenting simple survey data for exchange or archiving. Version 2.5 was released in January 2012.
  • DDI Lifecycle (or DDI versions 3 and 4) are richer and may be used to document datasets at each stage of their lifecycle from conceptualization through to publication and reuse. It is modular and extensible. Version 3.3 was published in April 2020. A beta for DDI 4 was released in 2025.

Both versions 2 and 3 are XML-based and are defined using XML Schemas. Version 4 supports XML, RDF, and JSON representations. They were developed and are maintained by the DDI Alliance.

FHIR (Fast Healthcare Interoperability Resources)

FHIR is a set of standards for the exchange of healthcare information and data. It defines metadata schemas for describing various entities relevant to healthcare – such as patients, procedures, and clinical reasoning – as well as protocols for exchanging data and metadata records between systems. The information may be serialized as XML, JSON, ND-JSON, or RDF/Turtle.

The Infrastructure Package was approved as standard ANSI/HL7 FHIR® R4 INFRASTRUCTURE R1-2019.

ODM (Operational Data Model)

ODM-XML is a data exchange standard, vendor-neutral, platform-independent suited for exchanging and archiving clinical and translational research data, along with their associated metadata, administrative data, reference data, and audit information. ODM-XML facilitates the regulatory-compliant acquisition, archival and exchange of metadata and data.

Wildlife Disease Data Standard

Our goal with the wildlife disease data standard is to describe interactions between hosts and parasites with sufficient detail and structure as to be useful, but not burdensome on the end user. In this case a parasite can be anything from a micro-parasite like a virus to a macro-parasite like a tick. We use this broad term because systems are complicated and a researcher may want to monitor interactions at multiple levels. The standard has two components disease data and project metadata. The disease data component describes the contents and structure of data related to the detection (or not) of a parasite in/on a given host and is focused on data exchange. The project metadata component describes the contents and structure of data related to the creation of the disease data component and is focused on data discovery. The disease data component allows us to create a collection of datasets that can be re-used, aggregated, and shared, while the project metadata component provides context for the data, makes it easier to find the dataset, and gives clear information about attribution and use