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Published on: March 19, 2018
An eligibility criteria query language for heterogeneous data warehouses
1R. Bache, Dept. of Primary Care and Public Health Sciences, Floor 7, Capital House, Weston Street, London SE1 3QD, UK,
A new clinician-readable query language simplifies clinical trial eligibility criteria (ECs) by abstracting data heterogeneity. This enables researchers to query diverse electronic health records effectively, improving clinical research efficiency.
Area of Science:
- Health Informatics
- Clinical Research Informatics
- Data Interoperability
Background:
- Electronic clinical data offers research potential but faces challenges due to data heterogeneity.
- Existing query languages struggle with diverse data representations, hindering consistent interrogation.
- A need exists for a higher-level, domain-specific language for data-representation-agnostic queries.
Purpose of the Study:
- To define a clinician-readable computational language for querying patient eligibility criteria (ECs) from clinical trials.
- To enable automatic evaluation of ECs on heterogeneous data sources, abstracting data complexity.
- To overcome limitations of standard query languages in diverse clinical data environments.
Main Methods:
- Developed a clinician-readable query language based on existing EC standards and examples.
- Implemented a model-based approach to transform ECs into queries for heterogeneous data warehouses.
- Evaluated the query language on two distinct data sources with differing structures and content.
Main Results:
- The query language abstracts expressivity, allowing EC construction without prior data source knowledge.
- Successfully evaluated on semantically and structurally diverse data warehouses.
- The language is utilized in the EHR4CR project and perceived as useful, understandable, and unambiguous by users.
Conclusions:
- An EC-specific language isolates researchers from data complexities, enabling effective querying of heterogeneous clinical data.
- The approach demonstrates the potential of domain query languages for overcoming semantic interoperability challenges.
- The developed language is usable, interoperable, and maintains semantic consistency across clinical domains.
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