An Etiology for Medication Ordering Errors in Computerized Provider Order Entry Systems

Medication errors cause adverse drug events in nearly 5 percent of the inpatient population. Research to understand causes of medication ordering error traditionally uses retrospective methods--such as case studies, chart reviews, or self-reported incidents--after the event has occurred. To address this, the research team embedded a prospective order error alert function, called the void alert tool (VAT), in the hospital’s inpatient computerized provider order entry (CPOE) system. The VAT was triggered for duplicate orders, drug interactions, orders placed for the wrong patient or encounter, and orders with the wrong medication route, dosage, schedule, or strength.

The specific aims of this research were as follows:

• Investigate clinician-provided reasons for CPOE-based medication voiding. 
• Identify medication ordering errors from voided orders and their clinical impact. 
• Develop statistical and descriptive models for characterizing medication ordering errors. 

The research team reviewed VAT data from 1,074 instances of ordering errors placed in a tertiary academic medical center over a 16-month period. When the VAT tool was triggered, researchers received a secure email containing detailed information about the voided order. When an order triggered the VAT, within 24 hours the research team followed up with the ordering clinicians to participate in an interview about the event. If the clinicians could not be reached within 24 hours to schedule an interview, they were asked to participate in a web-based survey. The purpose of the interviews and surveys was to identify elements of the medication ordering workflow that were risk factors for order errors, including people, their tasks, tools and technologies, physical environment, and organizational aspects. Finally, the research team conducted chart reviews on all 1,074 VAT-triggered orders to identify the type of ordering error, verify whether clinician-reported reasons for the ordering errors aligned with the chart review, and ascertain whether the error had an impact on patient safety.

The VAT tool has utility in both research and practice. Although no adverse drug events were reported within the study period, 22 percent of the ordering errors identified during the study period still reached the patient. All ordering errors were due to a combination of associated risk factors, such as inconsistent CPOE user interfaces between physicians and nurses, misinterpretation of verbal orders, communication gaps in the patient care team, audible noise from medical equipment, and workflow interruptions. Overall, the findings point to the need for multi-faceted strategies for ensuring medication ordering safety. Future research building on the use of VAT in CPOE systems has potential to inform clinical practice and prevent order error-related harm to patients.