AUTHOR=Chapman Sarah C. E. , Chan Amy H. Y. TITLE=Medication nonadherence - definition, measurement, prevalence, and causes: reflecting on the past 20 years and looking forwards JOURNAL=Frontiers in Pharmacology VOLUME=16 YEAR=2025 URL=https://www.frontiersin.org/journals/pharmacology/articles/10.3389/fphar.2025.1465059 DOI=10.3389/fphar.2025.1465059 ISSN=1663-9812