Electronic Prescribing and Electronic Transmission of Discharge Medication Lists

In the ambulatory setting, medication errors occur in approximately 8 to 21 percent of prescriptions and adverse drug events (ADEs) affect 25 percent of patients. Of those ADEs, 11 percent are preventable and 28 percent are ameliorable. Evidence indicates that health information technology (IT) decreases medication errors in the inpatient setting, but there is less evidence about outpatient settings and transitions from inpatient to outpatient settings. Moreover, most of this evidence has been driven by a few institutions that developed home-grown systems. The ability to generalize those findings to commercial systems that are more accessible to other institutions or providers is unclear.

This project used three approaches to measure the impact of electronic prescribing (e-prescribing) on patient safety in the ambulatory setting. The first was a multi-site, pre-post study measuring the effects of health IT on medication errors when transitioning from one electronic prescribing system to another, in this case from home-grown to a vendor-based system. The second study was a qualitative study to understand variations in human-computer interactions with the new electronic prescribing system and subsequent correlation with medication error rates. The third study was a cohort controlled study evaluating electronic transmission of discharge medication lists from the hospital to the ambulatory setting.

The specific aims of the study were to:

• Measure the effects on medication errors of transitioning from one e-prescribing system to another in the ambulatory setting.
• Measure the effects on human-computer interactions of transitioning from one e-prescribing system to another in the ambulatory setting.
• Evaluate the impact on medication discrepancies of electronic transmission of medication lists at discharge from the hospital to the ambulatory setting at the first ambulatory visit following discharge.
• Evaluate the impact on ADEs 30-days post-discharge of electronic transmission of medication lists at discharge from the hospital to the ambulatory setting.

The study results indicated that after transition to the new system, the prescribing error rate decreased over a 2-year period. The qualitative study with providers found that the transition was difficult for providers but that providers’ perceptions of usability and efficiency became more positive over time. Finally, the cohort controlled study did not find a reduction in the incidence of medication errors. The study demonstrated the importance of e-prescribing systems that support medication reconciliation and physician workflow.