Objectives: Electronic health records (EHRs) data are increasingly used for research and analysis, but there is little empirical evidence to inform how automated and manual assessments can be combined to efficiently assess data quality in large EHR repositories.
Materials and methods: The GEMINI database collected data from 462 226 patient admissions across 32 hospitals from 2021 to 2023. We report data quality issues identified through semi-automated and manual data quality assessments completed during the data collection phase. We conducted a simulation experiment to evaluate the relationship between the number of records reviewed manually, the detection of true data errors (true positives) and the number of manual chart abstraction errors (false positives) that required unnecessary investigation.
Results: The semi-automated data quality assessments identified 79 data quality issues requiring correction, of which 14 had a large impact, affecting at least 50% of records in the data. After resolving issues identified through semi-automated assessments, manual validation of 2676 patient encounters at 19 hospitals identified 4 new meaningful data errors (3 in transfusion data and 1 in physician identifiers), distributed across 4 hospitals. There were 365 manual chart abstraction errors, which required investigation by data analysts to identify as "false positives." These errors increased linearly with the number of charts reviewed manually. Simulation results demonstrate that all 3 transfusion data errors were identified with 95% sensitivity after manual review of 5 records, whereas 18 records were needed for the physician's table.
Discussion and conclusion: The GEMINI approach represents a scalable framework for data quality assessment and improvement in multisite EHR research databases. Manual data review is important but can be minimized to optimize the trade-off between true and false identification of data quality errors.
Keywords: clinical databases; data extraction; data quality; data validation; electronic health records; electronic medical records.
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