We found a nearly sevenfold reduction in error rates among community-based ambulatory providers using a commercially available stand-alone e-prescribing system, while error rates among non-adopters remained high.
Our study is one of the first to demonstrate a reduction in prescribing errors in ambulatory solo and small group community practices, where e-prescribing adoption and usage has lagged.20
The ability to demonstrate significant reductions in errors in this setting is important as an estimated 2.6 billion drugs are provided, prescribed, or continued at ambulatory care visits and national efforts are directed at promoting ambulatory e-prescribing adoption.21,22
Our rates of baseline prescribing errors are higher than those previously reported and highlight the importance of studying this setting. In a study using the same methodology of four academic primary care clinics, the number of prescriptions containing at least one error was 7.6% compared to our rate of 29.8–35%. Our error rates might be higher for several reasons. We studied community-based providers who may have different support systems and prescribing patterns compared to academically affiliated providers. There might also be variations in patient complexity or practice characteristics.
Differences in e-prescribing systems, including workflow integration and level of CDS, may help explain the inconclusive effects of e-prescribing on outpatient medication safety to date.3,7–10
However, some effectiveness has been shown in specific circumstances. For example, e-prescribing integrated into an EHR targeting potentially contraindicated medications in elderly patients reduced nonpreferred medication use.9
Another e-prescribing application decreased drug-lab interactions through an abnormal laboratory result alert.10
Finally, there was a decrease in warfarin drug interactions through an interaction alert in an integrated e-prescribing application.8
An important question not addressed by this study is whether e-prescribing systems integrated in EHRs are as effective as stand-alone systems. Currently most e-prescribing is done within EHRs.23
Integrated systems generally allow providers increased access to information at the time of prescription writing. However, stand-alone e-prescribing is generally less costly and easier to implement.4
It is unknown which system is better suited to provider workflow.
The commercial e-prescribing system we studied included many features recommended by an expert panel on e-prescribing applications.24
Features in commercial products, including levels of CDS, vary greatly, ranging from reactive alerts to more advanced features such as patient-specific dose checking. Of ten commercially available e-prescribing systems in 2002–2003, 64% had features classified as basic by an expert review panel and only 12% had the most advanced CDS.23
Both basic and advanced CDS appear important for improving ambulatory medication safety in our study, but their potential is still under-realized. After e-prescribing adoption, preventable errors remained. This suggests that content or representation of CDS is insufficient. Providers report that currently available commercial e-prescribing CDS applications is poorly designed, does not add value and does not lead to modification of prescribing choices.20
The less serious prescribing errors and illegibility errors are worth studying for their potential impact on safety and their impact on efficiency. In a study by Grossman and colleagues, most physicians rated improved legibility as the greatest benefit of e-prescribing because they believed it reduced pharmacy errors in filling prescriptions and callbacks for clarification.20
A study by Wang and colleagues also found that compared to paper prescribers, most e-prescribers reported having better information to reduce inefficiencies associated with pharmacy calls for potential safety problems.25
Providers who adopted e-prescribing in our study benefited from well-designed implementation and technical support as managed by MedAllies, a for-profit Health Information Service Provider.26
This included routine monitoring of e-prescribing compliance and ongoing support to encourage 100% use. A recent study examining e-prescribing implementation and usage among 12 ambulatory practices showed that unsuccessful practices reported more difficulties with technical aspects of implementation and insufficient technical support.27
Without extensive technical support, it is difficult to achieve high rates of use and subsequent improvements in medication safety. The importance of technical assistance has been recognized by the federal government, which is funding the Health Information Technology Extension Program for Regional Centers to provide technical support for providers adopting EHRs.2
Our study has several limitations. Although we attempted to ensure that prescribers used duplicate prescription pads, providers may have sometimes used non-duplicate prescriptions. This may have resulted in fewer paper prescriptions and account for the apparent increase in prescribing rates for adopters, as e-prescribing compliance was high and e-prescription retrieval was complete. Future studies should explicitly examine the effects of e-prescribing on prescribing rates.
We studied only 30 providers using a non-randomized design. Thus there may be differences between adopters and non-adopters not captured by our study. Providers were not blinded to the study’s purpose and may have been extra careful when prescribing, making our results conservative estimates of true error rates. Our study was conducted in one geographic region among small, private physician practices, limiting generalizability. We also studied only one stand-alone e-prescribing system, however this system is a popular commercially available system incorporating many features recommended by an expert panel.24
Future studies should be performed with more providers, at diverse sites, and with multiple systems.
We were also limited by our methodology to comment on preventable ADEs, as these are best detected by patient surveys.3
Although it is likely that stand-alone e-prescribing systems are effective in reducing preventable ADEs, future studies should explicitly evaluate this question.