Price, familiarity, and availability determine the choice of drug - a population-based survey five years after generic substitution was introduced in Finland.

Background: Mandatory generic substitution (GS) was introduced in Finland at the beginning of April 2003. However, individual patients or physicians may forbid the substitution. GS was a significant change for Finnish medicine users. It was thought it would confuse people when the names, colors, packages, etc., changed. The purpose of this study was to explore what medicine-related factors influence people's choice of prescription drugs five years after generic substitution was introduced in Finland.

Methods: A population survey was carried out during the autumn of 2008. A random sample was drawn from five mainland counties. A questionnaire was mailed to 3000 people at least 18 years old and living in Finland. The questionnaire consisted of both structured and open-ended questions. Factors that influenced the subjects' choice of medicines were asked with a structured question containing 11 propositions. Descriptive statistical analyses were performed.

Results: In total, 1844 questionnaires were returned (response rate, 62%). The percentage of female respondents was 55%. Price, availability, and familiarity were the three most important factors that influenced the choice of medicines. For the people who had refused GS, the familiarity of the medicine was the most important factor. For the subjects who had allowed GS and for those who had both refused and allowed GS, price was the most important factor.

Conclusions: The present study shows that price, familiarity, and availability were important factors in the choice of prescription medicines. The external characteristics of the medicines, for instance the color and shape of the tablet/capsule or the appearance of the package, were not significant characteristics for people.