ATC - Purpose and use

The main use of ATC/DDD is as a tool for producing drug use statistics. The system may be used in the registration process of drugs and collection of utilisation statistics in various settings and at different levels. Examples are sales data (local to national level), dispensing data (comprehensive or sampled), claims data (e.g. through health insurance organizations), patient encounter data, patient surveys, health facility data (e.g. health centres, hospitals, nursing homes). With the ATC system drug groupings are standardised for comparative analysis of units, settings or countries. By using the standard measuring unit (DDD/ 1000 inhabitants/day) rough estimates of the proportion of the population treated with certain drugs may be made.

In the Nordic countries, the ATC classification system is used as a national classification system to identify medicinal substances in products marketed in these countries. Manufacturers, wholesalers, pharmacies and regulatory authorities use the system as a common standard and all medicinal products marketed in the Nordic countries are assigned ATC codes. In order to use the ATC/DDD methodology for presenting drug use statistics, it is necessary to link ATC codes and DDDs to each drug pack.

The ATC system codes are available in national drug catalogues in countries that have adopted the ATC system as a national standard for medicinal products. Such catalogues contain all medicinal products registered for sale in that particular country and are often provided as supplement to electronic patient record systems to support electronic prescription forms and to facilitate communication between physicians and pharmacies.

At present there is no comprehensive information on the availability of ATC codes in national product catalogues world wide, but some general examples of national drug catalogues are:

The exact distribution of the ATC/DDD system world wide is not known. However, classification and guideline publications are sold to more than 80 countries. The extent to which the system is used in each country, and to what purpose, is also not known. In some countries it is being used for sales statistics, in other cases only for listing of substances/products. Unfortunately, in some cases the system is used for pricing or remuneration purposes, something it was never intended for.