Cost-effectiveness of a computerized provider order entry system in improving medication safety ambulatory care.

Background: Computerized provider order entry (CPOE) is the process of entering physician orders directly into an electronic health record. Although CPOE has been shown to improve medication safety and reduce health care costs, these improvements have been demonstrated largely in the inpatient setting; the cost-effectiveness in the ambulatory setting remains uncertain.

Objective: The objective was to estimate the cost-effectiveness of CPOE in reducing medication errors and adverse drug events (ADEs) in the ambulatory setting.

Methods: We created a decision-analytic model to estimate the cost-effectiveness of CPOE in a midsized (400 providers) multidisciplinary medical group over a 5-year time horizon- 2010 to 2014-the time frame during which health systems are implementing CPOE to meet Meaningful Use criteria. We adopted the medical group's perspective and utilized their costs, changes in efficiency, and actual number of medication errors and ADEs. One-way and probabilistic sensitivity analyses were conducted. Scenario analyses were explored.

Results: In the base case, CPOE dominated paper prescribing, that is, CPOE cost $18 million less than paper prescribing, and was associated with 1.5 million and 14,500 fewer medication errors and ADEs, respectively, over 5 years. In the scenario that reflected a practice group of five providers, CPOE cost $265,000 less than paper prescribing, was associated with 3875 and 39 fewer medication errors and ADEs, respectively, over 5 years, and was dominant in 80% of the simulations.

Conclusions: Our model suggests that the adoption of CPOE in the ambulatory setting provides excellent value for the investment, and is a cost-effective strategy to improve medication safety over a wide range of practice sizes.