Impact of Electronic Prescribing on Medication Use in Ambulatory Care

Published Online: December 23, 2013
Ashley R. Bergeron, MPH; Jennifer R. Webb, MA; Marina Serper, MD; Alex D. Federman, MD, MPH; William H. Shrank, MD, MSHS; Allison L. Russell, BA; and Michael S. Wolf, PhD, MPH
Objectives: To investigate differences before and after rollout of electronic prescribing (e-prescribing) in (1) patients’ primary adherence to newly prescribed medications, (2) patients' understanding of how to use their medications, and (3) multiple pharmacy use.

Study Design: Postvisit interviews and follow-up phone calls were done with 344 patients at an academic general internal medicine clinic.

Methods: Patient interviews and follow-up phone calls were done (1) before e-prescribing, (2) 1 to 6 months after e-prescribing, and (3) 12 to 18 months after e-prescribing.

Results: Overall, rates of abandoned prescriptions were 6.9% before e-prescribing, 10.6% 1 to 6 months after e-prescribing, and 2.5% 12 to 18 months after e-prescribing (P = .07). There was a reduction in awareness of the indication for a newly prescribed medicine among patients after e-prescribing (95.4%, 97.9%, and 89.8%, respectively; P = .03). There was a decrease in patients’ ability to demonstrate proper use of their new medicine after e-prescribing (69.0% before e-prescribing, 67.1% 1-6 months after e-prescribing, 51.9% 12 -18 months after e-prescribing; P = .02). There was an increasing trend in the percentage of patients using multiple pharmacies after e-prescribing was implemented.

Conclusions: We found both potential benefits and unexpected consequences as a result of the rollout of electronic prescribing. Adaptation to  e-prescribing might be improved with outreachand education, including explicitly informing patients of the change during the first months of rollout. Tangible prescription information for reminder purposes only may also be beneficial.

Am J Manag Care. 2013;19(12):1012-1017
Between 2009 and 2011, there was a 72% increase in electronic prescribing (e-prescribing), from 191 million to 326 million e-prescribed orders.1 From a quality and safety perspective, e-prescribing has been thought to have the potential to improve patient care by improving clinic efficiency, preventing medication errors, and even improving regimen adherence.2-8 Yet to date there is  limited evidence on the impact of e-prescribing on the patient experience in primary care, including adherence-related concerns.9-11

Despite the promise of e-prescribing to improve healthcare quality, a possible consequence could be primary nonadherence (ie,  e-prescriptions would actually negatively impact the timely retrieval and purchase of a new prescription). The hypothesis follows that despite the expedited order from prescriber to pharmacy, e-prescribing removes the known tangible reminder to fill a prescription by eliminating the paper prescription. Additionally, it is plausible that the nature of physicianpatient communication during a medical encounter on a newly prescribed medicine could change with greater efficiency, which may impact essential patient understanding of what a prescribed medicine is for (indication) and proper daily dosing. Beyond adherence concerns, the process of e-prescribing could lead to issues with medication reconciliation, as it requires patients to identify the pharmacy that they would like the order to be directed to; multiple pharmacies can be entered per patient (eg, pharmacy near work vs pharmacy closer to home). Multiple pharmacy use has been associated with lower compliance, higher risk of potentially dangerous or inappropriate drug combinations, and higher costs of pharmaceutical services.12-14

In 2009, our team was conducting baseline interviews as part of a clinical trial evaluating an electronic health record strategy to  promote safe, appropriate medication use. Six months later, the clinic implemented e-prescribing for the first time, allowing for a  natural experiment to take place. While it was not the original intention of the study, we identified a unique opportunity to leverage extensive data collection to explore several critical research questions. We were able to investigate differences before and up to 18 months after e-prescribing was implemented in the clinic in the following outcomes: (1) patients’ primary adherence to newly  prescribed medications as determined by rate of prescription abandonment (unfilled prescriptions) and delays in filling a prescription; (2) medication understanding  as determined by patient understanding of a new prescription medication’s indication and demonstrated proper use (number of pills per dose, times taken per day, total number of pills to be taken daily); and (3) multiple pharmacy use.


We conducted a cross-sectional evaluation examining the impact of e-prescribing implementation within 1 primary care clinic, with 3 waves of patient interviews. Specifically, 1 baseline assessment was conducted during the 6 months prior to the implementation of e-prescribing (before e-prescribing), and 2 posttest assessments were performed, the first during the 6 months after implementation of e-prescribing (e-prescribing interval 1) and the second 12 to 18 months after implementation of eprescribing (e-prescribing interval 2). 


Adult patients (N = 344) receiving care at 1 academic general internal medicine ambulatory care clinic were recruited between September 2009 and March 2011. Three cohorts of patients were recruited: 144 patients before e-prescribing, 127 patients during the first 6 months after e-prescribing, and 73 patients 12 to 18 months after e-prescribing implementation. Individuals were eligible if they (1) were 18 years  or older, (2) were established patients at the clinic, (3) had an appointment with their physician on the day of recruitment, and (4) received a new order for a prescription medication during their visit. Patients receiving only orders for refills (ie, no orders for a new prescription medication) were not eligible to participate, nor was anyone with a moderate to severe visual, hearing, or cognitive impairment as determined by clinical staff or the interviewer at the time of recruitment. If patients received both an order for a refill and an order for a new prescription, they were eligible to participate. Patients were also ineligible if they had participated in an earlier interview wave for this study. The Northwestern University Institutional Review Board approved the study prior to its initiation.


Trained research interviewers working with clinic physicians and staff identified eligible patients upon their medical encounter at discharge. Specifically, clerical staff provided patients at check-in and discharge with a flyer that described the study in some detail as well as eligibility requirements. Staff directed interested patients to the available research staff who were waiting on site. Those who consented to participate then completed a brief, interviewer-assisted survey that included a literacy assessment. Interviewers notified patients they would receive  a follow-up phone call with additional questions about their prescription, such as if and when they filled the medication and how they were taking it.


Patients provided information regarding age, sex, marital status, race, education, income, type of insurance, number of medications currently prescribed, and number of comorbid conditions. Each patient also completed the Rapid Estimate of Adult Literacy in Medicine to assess literacy. The encounter discharge summary was reviewed to obtain the name, dose, and frequency information for the newly prescribed medication. Follow-up phone interviews occurred from as early as 6 days to as long as 2 weeks after the initial interview. During these follow-up phone interviews, appropriate medication knowledge (indication, side effects) and proper use (number of pills, number of times per day, time of day) were assessed. Additionally, patients were asked if they had filled their prescription, and if not, the reason for not obtaining the medication and the number of pharmacies used.

Statistical Analyses

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Issue: December 2013
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