Exploring the validity of US Pharmacopeia pictograms among young Spanish citizens who have completed secondary education.

Abstract

This study aimed to explore the validity of US Pharmacopeia pictograms among young Spanish citizens who have completed secondary education. A multicenter cross-sectional study was conducted in Melilla, Spain, with young citizens who completed secondary education in 2021-2022, recruited through convenience sampling. A random selection of US Pharmacopeia pictograms was assessed to examine comprehension results and their relationship with relevant sociodemographic variables and Health Literacy measured using the validated questionnaire (HLS-EU-Q16). Only pictograms meeting the ISO comprehensibility threshold of 66.70 % upon initial presentation were considered valid. Simple linear regression analyzed user factors affecting pictogram comprehension, and significant variables (p < 0.05) were included in a multiple regression to evaluate their combined effect. Of the 20 pictograms evaluated, 12 met the minimum comprehensibility threshold. Some safety-related pictograms showed particularly low results. For instance, the pictogram intended to convey "flammable" had a notably low comprehensibility rate (29.33 %). Health literacy was the strongest predictor of comprehension, with higher scores among individuals with high Health literacy (67.77 %) compared to those with low Health literacy (61.79 %). The multivariate model confirmed that Health literacy (p = 10⁻⁴), male gender (p = 0.029), non-European origin (p = 0.034), and age (p = 0.037) were associated with lower comprehension. US Pharmacopeia pictograms do not achieve sufficient comprehensibility to ensure the safe and appropriate use of medications in this population. New pictograms will need to be developed or existing ones reconceptualized to ensure valid use within this population. Enhancing Health Literacy education in schools is crucial for improving the comprehension of pharmaceutical pictograms, ensuring their effective application in health communication strategies.