JMIR Publications

ABSTRACT

Background:

Large-scale international real-world evidence generation benefits from terminology harmonization. Despite widespread adoption of standardized vocabularies, their effective use and long-term sustainability at scale remain poorly understood.

Objective:

To examine real-world terminology and code use in data across a federated network of observational data sources.

Methods:

We conducted a two-part survey of the researchers and data owners within the Observational Health Data Sciences and Informatics (OHDSI) community on their terminology usage, challenges, and needs, accompanied by the analysis of code usage across a subset of real-world data sources.

Results:

Survey covered 144 institutions across the US, UK, Europe, Asia, and Africa. Data on terminology use covered 60 sources and 22 data sources supplying detailed code-level utilization information. We observed significant variations in terminology usage, with 61 out of 89 terminologies used in the data present in less than 10% of the data sources. Code use even after data harmonization was also highly variable: only 1% of codes were found in all data sources. Mapping and hierarchy completeness, terminology coverage, versioning and terminology changes were among the most common challenges. We outlined several of our subsequent process improvements: community contribution and stewardship pipelines, metadata for relationships, and informatics tools for assessment of the impact of terminology change.

Conclusions:

Terminology and coding inconsistencies across observational data sources require a standardized terminology system. Such a system is complex and time-consuming and need community contribution and informatics solutions for harmonization to be scalable and sustainable. Even with a common reference standard high heterogeneity of terminology and code utilization across different observational data sources remains.