Objective: To assess the efficacy of patient-centered label (PCL) instructions on the knowledge and comprehension of prescription drug use compared to standard instructions.
Methods: A total of 94 participants recruited from an outpatient clinic in Ireland were each randomly assigned to receive: (1) standard prescription instructions written as times per day (usual care), (2) PCL instructions that specify explicit timing with standard intervals (morning, noon, evening, bedtime) or with mealtime anchors (both PCL), or (3) PCL instructions with a graphic aid to visually depict dose and timing of the medication (PCL + Graphic). The outcome was correct interpretation of the instructions.
Results: PCL instructions were more likely to be correctly interpreted than the standard instructions [adjusted relative risk (RR) 1.08, 95% confidence interval (CI) 0.98-1.18]. The inclusion of the graphic aid (PCL + Graphic) decreased the rates of correct interpretation compared to PCL instructions alone (RR 0.98, 95% CI 0.91-1.05). There was a significant interaction between instruction type and health literacy (p = 0.01). Those with limited health literacy were more likely to correctly interpret the PCL labels (91%) than the standard labels (66%), and those with adequate health literacy performed equally well.
Conclusion: The PCL approach may improve patients' understanding and use of their medication regimen.