Electronic prescribing within an electronic health record reduces ambulatory prescribing errors

Health policy forces are promoting the adoption of interoperable electronic health records (EHRs) with electronic prescribing (e-prescribing). Despite the promise of EHRs with e-prescribing to improve medication safety in ambulatory care settings--where most prescribing occurs and where errors are common--few studies have demonstrated its effectiveness. A study was conducted to assess the effect of an e-prescribing system with clinical decision support, including checks for drug allergies and drug-drug interactions, that was integrated within an EHR on rates of ambulatory prescribing errors.

In a prospective study using a nonrandomized, pre-post design with concurrent controls, 6 providers who used a commercial e-prescribing system were compared with 15 providers who remained paper-based from September 2005 through July 2008. Prescribing errors were identified by a standardized prescription and chart review.

Some 2,432 paper prescriptions at baseline and 2,079 prescriptions at one year were analyzed. Error rates for e-prescribing adopters decreased 1.5-fold--from 26.0 errors per 100 prescriptions at baseline (95% confidence interval [CI], 17.4-38.9) to 16.0 errors per 100 prescriptions at one year (95% CI, 12.7-20.2; p = .09). Error rates remained unchanged for nonadopters (37.3 per 100 prescriptions at baseline, 95% CI, 27.6-50.2, versus 38.4 per 100 prescriptions at one year, 95% CI 27.4-53.9; p = .54). Error rates for e-prescribing adopters were significantly lower than for nonadopters at one year (p < .001). Illegibility errors were high at baseline and eliminated by e-prescribing.

The preliminary findings from this small group of providers suggest that e-prescribing systems may decrease ambulatory prescribing errors, which are occurring at high rates among community-based providers.