Drug utilization studies are an important tool for drug regulators particularly in improving rational drug use and providing data for cost/benefit considerations. WHO should assist drug regulatory authorities by:

1. Encouraging studies of actual use and consumption of drugs by relating pharmacotherapy to the actual disease.

2. Promoting quality of the data by ensuring that the source of the data is accurate and establishing a system of data collection.

3. Raising awareness of how Anatomic-Therapeutic-Chemical (ATC) and Defined Daily Doses (DDDs) are developed through educational programmes in order to prevent misinterpretation and misuse of ATC/DDD.

4. Adopting or adapting manuals for use of the ATC/DDD classification at local level with reference to the manuals prepared by the WHO Collaborating Centre on Drug Statistics Methodology in Oslo, Norway.

5. Promoting greater awareness of changes in the ATC/DDD classification system and establishing conditions for the regular updating of national classification systems.