Effect of pharmaceutical pictograms on the textual comprehension of Prescription Medication Leaflets: A randomized controlled trial.

Introduction: Clear patient instructions are essential in pharmaceutical care. However, literature reveals a consistent gap between the readability of medication messages and population skills. This study aimed to assess the comprehension of information in three Prescription Medication Leaflets, with and without supplementary US Pharmacopeia (USP) pictograms, among Spanish adolescents completing secondary education.

Methods: We conducted a multicenter randomized controlled trial. From March to June 2022, 590 students were randomly assigned to read Prescription Medication Leaflets for ibuprofen, amoxicillin/clavulanic acid, and omeprazole, with or without USP pictograms. Comprehension was evaluated via questionnaire, alongside the European Health Literacy Survey short form, and sociodemographic data were collected. Mann-Whitney U and chi-square tests were used for analysis.

Results: Participant comprehension was significantly below the European standard, which requires at least 80 % readability for Prescription Medication Leaflets, even with pictograms. Pictograms, however, significantly enhanced comprehension across all medication package inserts (p < 0.001 for all comparisons), especially among students with higher health literacy. High health literacy was a statistically significant factor in comprehension only within the experimental group (p = 0.005; p = 0.039; p = 0.004).

Conclusion: The discouraging results highlight the imperative for innovation in medication labeling design, employing patient-centered approaches. USP pictograms have been shown to significantly enhance the reading comprehension of medication package inserts among the Spanish population.