Wen, Andrew

Abstract Objective To design, develop, and evaluate a scalable clinical data normalization pipeline for standardizing unstructured electronic health record (EHR) data leveraging the HL7 Fast Healthcare Interoperability Resources (FHIR) specification. Methods We established an FHIR-based clinical data normalization pipeline known as NLP2FHIR that mainly comprises: (1) a module for a core natural language processing (NLP) engine with an FHIR-based type system; (2) a module for integrating structured data; and (3) a module for content normalization. We evaluated the FHIR modeling capability focusing on core clinical resources such as Condition, Procedure, MedicationStatement (including Medication), and FamilyMemberHistory using Mayo Clinic’s unstructured EHR data. We constructed a gold standard reusing annotation corpora from previous NLP projects. Results A total of 30 mapping rules, 62 normalization rules, and 11 NLP-specific FHIR extensions were created and implemented in the NLP2FHIR pipeline. The elements that need to integrate structured data from each clinical resource were identified. The performance of unstructured data modeling achieved F scores ranging from 0.69 to 0.99 for various FHIR element representations (0.69–0.99 for Condition; 0.75–0.84 for Procedure; 0.71–0.99 for MedicationStatement; and 0.75–0.95 for FamilyMemberHistory). Conclusion We demonstrated that the NLP2FHIR pipeline is feasible for modeling unstructured EHR data and integrating structured elements into the model. The outcomes of this work provide standards-based tools of clinical data normalization that is indispensable for enabling portable EHR-driven phenotyping and large-scale data analytics, as well as useful insights for future developments of the FHIR specifications with regard to handling unstructured clinical data.

AbstractObjectivesTo create test collections for evaluating clinical information retrieval (IR) systems and advancing clinical IR research.Materials and MethodsElectronic health record (EHR) data, including structured and free-text data, from 45 000 patients who are a part of the Mayo Clinic Biobank cohort was retrieved from the clinical data warehouse. The clinical IR system indexed a total of 42 million free-text EHR documents. The search queries consisted of 56 topics developed through a collaboration between Mayo Clinic and Oregon Health & Science University. We described the creation of test collections, including a to-be-evaluated document pool using five retrieval models, and human assessment guidelines. We analyzed the relevance judgment results in terms of human agreement and time spent, and results of three levels of relevance, and reported performance of five retrieval models.ResultsThe two judges had a moderate overall agreement with a Kappa value of 0.49, spent a consistent amount of time judging the relevance, and were able to identify easy and difficult topics. The conventional retrieval model performed best on most topics while a concept-based retrieval model had better performance on the topics requiring conceptual level retrieval.DiscussionIR can provide an alternate approach to leveraging clinical narratives for patient information discovery as it is less dependent on semantics. Our study showed the feasibility of test collections along with a few challenges.ConclusionThe conventional test collections for evaluating the IR system show potential for successfully evaluating clinical IR systems with a few challenges to be investigated.