An analysis of laboratory order entry errors on randomly selected inpatient records was conducted comparing errors 12 months before and after implementation of an electronic health record (EHR) at a 571-bed community health system. Methods: A total of 720 medical records were reviewed with 10,176 orders before EHR implementation and 11,455 orders after. Errors evaluated included unsigned, duplicate, illegible, and omitted orders, results with no order, and transcription errors. Data analysis included the independent-samples t-test and Pearson Chi-square test.Results: There was a significant difference in laboratory order entry errors before and after EHR implementation (p<0.05). The percentages of unsigned orders decreased from 8.6% to 7.6%. Orders with missing results decreased from 16.5% to 11.3%, and duplicate orders decreased from 9.1% to 5.8%. Added, illegible, missing, and incorrectly transcribed orders with previous rates of 3.72%, 0.8%, 2.8%, and 0.9% were eliminated. Conclusion: Implementation of an EHR appears to improve clinical laboratory order entry. ABBREVIATIONS: CMS-Centers for Medicare & Medicaid Services, CPOE-computerized physician order entry, CQM-clinical quality measures, EHRelectronic health record, LOS-length of stay, LISlaboratory information system, HIS-hospital information system, HIM-health information management, HPF-horizon patient folder, QI-quality indicator, IQR-Interquartile Range.INDEX TERMS: Electronic health records, medical order entry systems, hospital information systems, centers for Medicare and Medicaid services (U.S.), medical errors, patient care, patient safety Clin