When is a text userfriendly - and what does it mean to be userfriendly?

Modern-day consumers, citizens and patients demand comprehensible information. Expert advice is no longer swallowed raw, especially not if people are left with a feeling of not fully understanding the information and its consequences for them personally. The concept of userfriendliness, or readability, has therefore become central to the external communication of many companies or public organisations along with the realization that things may run more smoothly if the intended receivers of information actually understand it and are able to act upon it. But what does it mean to be userfriendly? Is it only a question of replacing a few expert terms and removing passive constructions or are other changes required as well? For a good number of years we have worked within medical expert-layman communication both as researchers and as consultant to the industry and we have reached a stage where we would like to have more systematic knowledge about the parameters which determine the userfriendliness of a text. The aim of this paper is therefore to examine and discuss the concept of userfriendliness first from a theoretical point of view and then on the basis of an empirical project testing the userfriendliness of Danish medicinal documentation.