Recording of drug prescriptions in the county of Jämtland, Sweden. I. Methodological aspects.

Prescribed drugs dispensed to 13% (17000) of the inhabitants in the county of Jämtland, Sweden, have been continuously recorded since 1970. Individual patients in the investigation are fully identifiable by their identity number as used in Sweden, so patients exposed to a particular drug or group of drugs can be reached subsequently, e. g. for studies of the incidence and nature of side effects. The following information is coded at the local pharmacies: prescribing physician, dispensing pharmacy, year and week of dispensation, name, amount and price of drug, dosage, type of prescription record. In a five year period the drop-out rate has decreased from 9% in 1970 to 4% in 1974. Every year at least one drug is prescribed for approximately 60% of the population. During the five year period 74% of the male and 80% of the female population purchased prescription drugs. The representative nature of the data is discussed, as well as their value in detection of irrational drug usage and ascertaining any particular patient's drug history.