Comparison of 2 electronic health record data extraction methods for laboratory tests used in the Veterans Aging Cohort Study Index
Abstract: Objective: To compare Observational Medical Outcomes Partnership (OMOP) Logical Observation Identifiers Names and Codes (LOINC) and Veterans Aging Cohort Study (VACS) methods for extracting laboratory chemistry data from Veterans Health Administration (VA) electronic health records (EHR). Materials and Methods: Laboratory chemistry test results for 16 laboratory tests commonly assess in Veterans in VACS HIV (N = 143 830) followed in the VA 2015-2019 were extracted from the EHR and compared using 2 different data extraction approaches. Results: The LOINC approach captured laboratory results from all 130 VA stations for all 16 labs. The VACS approach captured laboratory results from 128 to130 stations. Both approaches yielded laboratory results for a patient on a given date for 97% or more of the observations for 10 of the tests, 94%-97% for 5 of the tests, and 89% for 1 test. The percentage of exact matches on the value of the test result exceeded 99% for 10 of the laboratory tests and 92% for all other laboratory tests. Discussion: Both approaches resulted in extraction of similar amounts of data in terms of individual patients, VA stations and total observations for all 16 tests. Both approaches yielded high agreement on test results in terms of identical values and correlation of test results for all tests. Conclusion: The high level of agreement between VACS and LOINC approaches in this study demonstrate the favorable use of the LOINC approach for extracting laboratory results for most tests due to the ease and efficiency of this approach without compromising validity. This study compared Observational Medical Outcomes Partnership (OMOP) Logical Observation Identifiers Names and Codes (LOINC) and Veterans Aging Cohort Study (VACS) methods for extracting test results for 16 common laboratory tests (eg, cholesterol, glucose) from Veterans Health Administration (VA) electronic health records (EHR). Both approaches resulted in extraction of similar amounts of data in terms of individual patients, VA stations and total observations for all 16 tests. Both approaches yielded high agreement on test results in terms of identical values and correlation of test results for all tests. The high level of agreement between VACS and LOINC approaches in this study demonstrates the favorable use of the LOINC approach for extracting laboratory results for most tests due to the ease and efficiency of this approach without compromising validity.