Impact of a physician's order entry (POE) system on physicians' ordering patterns and patient length of stay

Objective: To investigate the impact of a physician's order entry (POE) system on physicians' ordering patterns and patient length of stay. Design: Prospective time series study at pre-POE, 3 months and 6 months after POE at a tertiary teaching hospital in Korea. The study period was from June 1999 to May 2000. Measurements: The number of orders (doctor's, PRN, medication, changed, canceled orders), number of tests (complete blood count, chemistry, chest X-ray, stat laboratory, serum electrolytes tests), appropriateness and length of patient stay were measured through chart review of 171 in-patients (liver disease, renal disease, gastrectomy, simple mastectomy). Results: The number of doctors' orders, PRN, and medication orders significantly increased after POE. The numbers of changed and canceled orders were not significantly different between pre- and post-POE. The number of stat lab tests significantly decreased after POE. There was no change in appropriateness of patients' hospital stay between pre- and post-POE. Length of stay significantly decreased (P=0.049). Conclusion: POE contributed to improving the quality of care in two ways: improvement of auditability by recording the medical services for patients in more precise and transparent manner, and more appropriate utilization of resources by decreasing the number of stat diagnostic tests and length of stay.