Vulnerability of a New Zealand hospital computerised provider order entry system to prescribing error: a comparative study with other systems.

Background: The computerised provider order entry (CPOE) system MedChart is going to be the national CPOE system in New Zealand's public hospitals.

Aims: We tested the vulnerability of our health region configuration of MedChart and its clinical decision support (CDS) to prescription ordering errors and compared it to other CPOE systems. We also tested whether ordering workflow influenced system vulnerability.

Methods: Ten testers completed 16 published scenarios simulating ordering errors in a training environment of MedChart. The difficulty of completing each scenario was recorded using a five-point Likert scale (1 = easily, 5 = impossible). Difficulty scores were summarised for each scenario. Sub-group analysis was conducted based on whether testers ordered sequentially or concurrently for scenarios involving two prescriptions.

Results: MedChart best protected (difficulty score 5) against omission and mixed frequency errors. Worst protections (difficulty score 1) were against drug-drug interaction, duplicate ordering error, wrong frequency for medicine form error, and under dosing error scenarios. Compared to other CPOE systems, MedChart provided better protection against more than half of the scenarios, but similar vulnerabilities were identified. Sequential versus concurrent ordering workflows significantly altered system protections for only one test scenario involving duplicate enoxaparin orders (median 3.0 vs 1.0, P = 0.004).

Conclusions: These findings highlight areas for improvement in MedChart system configuration. Different ordering workflows require consideration when implementing CDS. Publication of CPOE testing using standardised tools could facilitate comparison of safety performance between institutions.