Drug Utilization: ATC/DDD
Drug statistics methodology
The Anatomical, Therapeutic and Chemical (ATC) classification system and the Defined Daily Dose (DDD) are recommended by WHO for measuring drug utilization in countries. The WHO Collaborating Centre for Drug Statistics Methodology in Oslo, Norway (WHO CC, Oslo), develops and maintains the ATC/DDD system. An International Working Group meets twice a year to guide the Centre in this work.