This study investigated whether degree of audible struggle can be used to categorically distinguish childhood stuttered disfluencies from normal disfluencies. Twenty-nine first-year graduate students in communication disorders listened, on two occasions, to 100 disfluent utterances provided by 10 preschool-aged children. Fourteen listeners judged whether each utterance was stuttered or not stuttered, and 15 listeners used a 7-point scale to rate the degree of struggle heard in each utterance. Binary logistic regression analysis indicated that as the perception of degree of struggle increased, so did the likelihood that the disfluent production would be judged as stuttered ( p < 0.00001). For those utterances having high agreement regarding disfluency classification, average ratings of struggle were found to categorically distinguish between stuttered and nonstuttered classes of disfluency. It is suggested that a rating scale for degree of struggle may be a useful clinical tool for diagnosing childhood stuttering. Further study is needed to more fully explore the potential applications of such a tool.

This report was prepared under contract to the U.S. Geological Survey and has not been reviewed for conformity with USGS editorial standards. Opinions and conclusions expressed herein do not necessarily represent those of the USGS.

This report is one of a series of reports that present, chiefly with maps at a scale of 1 :250,000 and 1 :500,000, various aspects of the geology, geochemistry, geophysics, and mineral resources of the Dillon 1 °X2° quadrangle, southwestern Montana and east-central Idaho (fig. 1 ). These studies were made largely under the Conterminous United States Mineral Assessment Program (CUSMAP), the chief purpose of which is to determine the . mineral resource potential of selected quadrangles by means of a multidisciplinary approach. CUSMAP is intended to provide information on mineral resources to assist federal, state, and local governments in formulating minerals policy and land-use policy and to produce sound scientific data that may be of value to private industry and the general public in mineral exploration and development.