Cluttering Assessment Program (Version 2.02)

Software developed by Klaas Bakker


One way to assess cluttering severity is through determining percentage talking time cluttered (see Bakker et al, 2005 a, b). Basic to this method is that a clinician determines both talking time (the accumulative duration of speech sound) and cluttering time (the accumulative duration of time during which cluttering is perceived). These values are converted to a percentage measure to express how much of speech is perceptually affected by cluttering.

The measure may, of course, be taken with a stopwatch while listening to the same sample twice, one time to determine talking time, and a second time to determine cluttering time. The downloadable software makes this process more convenient and allows you to do it all at once, while providing the results in final form instantly.

For background information about this system one is referred to the original sources (Bakker et al, 2005 a, b). The most available original source is an online paper presented at the International Stuttering Awareness Day Conference (2005; accessible through the Stuttering Homepage). This link is still active as all previous conferences are available in archived form. The download option suggested below may be safer and more effective as it provides a complete set of setup files that may be needed on one’s system. This new option, then, is the most trouble free method for installing the program on one’s computer and less dependent on specific versions of one’s operating system.

The program is only available for PCs running on Windows (XP, and also Vista). For various reasons it is impractical to develop a similar version for Macintosh computers (for example the mouse on most Macintosh computers has only one button).

The system is currently being revised to make determination of talking time automatic, thus giving the clinician the ability to completely focus on possible cluttering. It is anticipated that the first version with automatic talking time determination can be downloaded from this site by the end of this year (2009).

The software is intended as freeware. There are no restrictions (sharing it is encouraged!). Its use is,however, at one’s own risk. That is, the author cannot assume liability for its use, or how it works on one’s particular system. A ‘research version’ is available on request, which has an advantage in that it has a reportable timing accuracy. If this is not needed, the downloadable version is more convenient and complete.

Comments and suggestions are welcome!

Start your download here!

NEW (Nov,2008)! The Cluttering Assessment Program (version 2.02) is also available in a version consistent with the new cluttering severity assessment system proposed by Bakker and Myers (2008). It is a temporary version that will be available online until the new program (with the automatic talking time option) will be made available on this site to replace all previous versions. The only difference compared to the original version is that some aspects of the perceptual rating scales have been changed. The upgraded version is guaranteed to work after you installed the original version first (!). Download the upgrade here!

The new program that will contain the automatic talking time determination option should be available on this website by the end of this year.


(Instructions: the download allows you to save setup information on your computer in the form of a *.zip file; click on it to extract the setup files; now select all files and move them onto your own system at a desired location such as for example your desktop; now click on "setup" to start the installation process and follow the instructions on your screen).



          Bakker, K., & Myers, F. L., (2008). A Comprehensive Measure of Cluttering Severity. Annual Convention of the American Speech Language and Hearing Association, Chicago, IL. 

          Bakker, K., St. Louis, K. O., Myers, F. L., & Raphael, L. J. (2005 a). Computer aided assessment of cluttering severity. Paper presented at the 8th International Stuttering Awareness Day On-Line Conference. October, 2005.


          Bakker, K., St Louis, K. O., Myers, F., and Raphael, L., (2005 b). A freeware software tool for determining aspects of cluttering severity. Annual National Convention of the American Speech Language and Hearing Association, San Diego, CA, USA.