Classification of pharmaceutical products reimbursed by National Health Insurance by the ATC System

In order to perform drug utilization studies of the National Health Insurance (NHI), it is necessary to establish a structural system for pharmaceutical classification. This study applied the Anatomical Therapeutic Chemical (ATC) classification to categorize the pharmaceutical products reimbursed by NHI. Each of the 20,469items was assigned an ATC code in a predefined procedure, and the therapeutic and/or pharmacological characteristic was then identified. The disadvantage of the previous American Hospital Formulary System (AHFS) coding was also examined in this study. The coding and related database was documenyted in an electronic file. Therefore, this electronic reference system can be utilized as a tool to analyze the NHI database for auditing drug utilization patterns, detecting drug related problems, and monitoring therapeutic outcomes.