Rationale and design of a randomized trial to evaluate an evidence-based prescription drug label on actual medication use
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Published on: September 20, 2019
William H Shrank1, Ruth Parker, Terry Davis
1Division of Pharmacoepidemiology and Pharmacoeconomics, Brigham and Women's Hospital and Harvard Medical School, 1620 Tremont Street, Suite 300, Boston, MA 02120, USA. wshrank@partners.org
Background:
Medication errors are an important public health concern, and poor understanding of medication labels are a root cause. Research shows that labels are variable, of poor quality, and not patient-centered. No real-world trials have evaluated whether improved medication labels can affect appropriate medication use, adherence or health outcomes.
Trial Design:
We developed an evidence-based prescription label that addresses both content and format. The enhanced label includes a universal medication schedule (UMS) that standardizes the directions for use incorporating 1) standard time periods for administration (morning, noon, evening, and bedtime), 2) numeric vs. alpha characters, 3) 'carriage returns' to separate daily dose and 4) a graphic aid to visually depict dose and frequency. We will evaluate the effect of providing this label to randomly sampled patients who receive their care from free clinics, mobile vans and federally qualified health centers (FQHCs) in Northern Virginia. We will recruit patients with diabetes or hypertension; these patients will be randomly assigned to receive all of their medications with improved labels or to receive prescriptions with standard labels. The primary outcome will be the patient's ability to correctly demonstrate dosing instructions. Other outcomes include adherence, error rates and health outcomes.
Conclusion:
To our knowledge, this trial is the first to evaluate the effect of prescription label improvement on understanding, medication use and outcomes in a clinical setting. If successful, these findings could be implemented broadly to promote safe and appropriate medication use and to support evidence-based standards in the development of labels.
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