The selection of "fluent" samples in research on stuttering: conceptual and methodological considerations.

The characteristics of stutterers' fluency has been the object of much research in recent years, but it is not always clear what the term "fluency" refers to in this research. This paper reviews the concept of fluency and considers the ways in which it has been employed in research on stuttering. The methods that have been used to identify fluent intervals in stutterers' speech are reviewed along with their reliability and validity. It is concluded that there is an urgent need to clarify the reference for fluency in such studies, and to develop procedures for measuring and quantifying fluency. Additional avenues for research are also discussed.