The defined daily dose as a measure of drug consumption in South Africa. A preliminary study.

OBJECTIVE

To perform a preliminary investigation into the us e of the defined daily dose (DDD) as a unit to measure drug utilisation in South Africa. The DDD methodology has been applied in many countries in Western Europe and in other parts of the world. However, research using the DDD method is still lacking in South Africa despite the important role that it can play in economic planning and the improvement of prescribing practices.

DESIGN

A retrospective drug utilisation study using da ta from a medical aid. Consumption of selected central nervous system drugs in a formulary system was determined.

SETTING

Doctors and patients located in an area of Port Elizabeth.

PARTICIPANTS

The prescribing behavior of 50 dispensing doctors serving a homogeneous demographic and socioeconomic patient population was analysed.

OUTCOME MEASUREMENTS: The DDD/1,000 registered patients/day, the cost per DDD and the relationship between the two units.

RESULTS

Values for the DDD/1,000 registered patients/day were on average lower than international values, but similar trends were observed. The cost per DDD for antipsychotic and antidepressant drugs was on average higher than for hypnotic and anxiolytic drugs. There was an inverse relationship between the DDD/1,000 registered patients/day and the cost per DDD.

CONCLUSIONS

The DDD methodology is a useful technique to enable drug consumption data to be measured and compared both nationally and internationally. It can be regarded as a valuable tool for the promotion of rational and cost-effective use of medicine in a future health care system for South Africa.