Diaphragmatic Breathing Video: Although stuttering is not caused by a breathing problem, our breath is the fuel that runs our voice or vocal folds. Proper coordination of the breath with the vocal fold vibrations is something that can greatly assist in fluent speech production. The breath can also become uncoordinated, and abnormal breathing patterns can be formed as a result of stuttering and the closure and tension in the vocal folds.
Fluency-Predictive Cluttering Inventory. Just looked this up: "Preliminary data suggest that a Score of 120+ indicates a diagnosis of cluttering. Scores between 80 and 120 indicate a diagnosis of cluttering-stuttering. "