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     At this time, the Clinical Issues Committee shares only one document descriving helpful suggestions for the Assessment of Cluttering. A similar document with suggestions for the treatment of cluttering is in development.




Cluttering Assessment*


Clinical Issues Committee of the ICA:

Yvonne van Zaalen op't Hof

Florence Myers

David Ward

Ellen Bennett




    Case history

     Oral reading

     Spontaneous speech



     Computer based assessment tool

     Self assessment


     Differential diagnostics with other disorders






                                           Drawing by Arend van Dam, as it appeared in:

Dinger, Smit and Winkelman (2004)

"Expressiever en Gemakkelijker Spreken"

Coutinho, Bussum, The Netherlands



The decision regarding whether or not cluttering is present must consider whether a client manifests cluttering in a relatively pure form or in conjunction with other  disorders, and particularly, stuttering. In the latter case, it is important to recognize that cluttering sometimes does not emerge as a salient condition until stuttering has remitted, either spontaneously or from treatment, or at least until treatment for stuttering is underway. Also, it is important to document the possible presence of other coexisting communication, learning, or attention deficit hyperactivity disorders.


Case history

As in most speech-language evaluations, the case history should include information regarding the following aspects of development:

  1. The primary reason why the person has presented for assessment (and potentially for treatment)
  2. Birth and developmental history
  3. Medical history
  4. Onset, course, previous treatment (and efficacy of previous therapy)
  5. Family history of speech or language disorders including fluency disorders and tachylalia
  6. History of any learning and behavioral problems in school or work settings (given the likelihood of coexistence of cluttering with such disorders as attention deficit hyperactivity disorders, learning disabilities, and auditory processing disorders).


We recommend digital video- and audio recording of the person who clutters in a variety of speaking tasks for subsequent analyses of fluency, rate, articulation, language, and voice.  The clinician should be aware that the client may try to “normalize” speech behaviors when being recorded, by comparing client’s communication behaviors when being recorded and when speaking extemporaneously when not being recorded.


Cluttering assessment should include different tasks to include oral reading, spontaneous speech, retelling a memorized story, a test of oral motor coordination and questionnaires.  Cluttering severity may vary depending on the nature of the speaking task. Cluttering behaviors are more likely to surface as the speaking task is more extemporaneous and informal, less structured,  more emotional, and linguistically more complex.


Oral reading

The nature of the oral reading task will limit the possibilities for language formulation difficulties in the clutterer; however, omission of syllables and words (particularly pronouns and articles) may occur. Take note of errors in syllable and word structure such as  telescoping of syllables or semantic paraphasias. Because the level of reading material may influence degree of cluttering, present clients with appropriate reading material that vary in reading difficulty. The more difficult passages, containing more multisyllabic words and linguistically more complex sentences, may produce more cluttering behaviors compared to the less difficult passages. It is also suggested that the client read a passage with and one without preparation, to compare the results of the prepared and unprepared reading.


Spontaneous speech

Engage the client in a more relaxed exchange on a subject that is of high interest to the client. This can include explaining a videogame, telling about his favorite sport or leisure activity, or telling a story about a recent exciting event that the client experienced. Record at least 10 minutes of of this language sample. The language sample should consist of a narrative rather than iterations of events as in a list. We have found that cluttering behaviors become more evident the more informal, spontaneous and extensive the talk. When the client is not aware of the recording you will have the highest chance of recording “uncontrolled” cluttering speech. Such speech may also be observed when recording the interaction between, for instance, the parent and the child, or the adult and partner while you leave the room for a while.



Assessment of articulation should include tasks that range from short and structured tasks, to longer and less structured tasks.  Examples of the former include rote tasks such as counting or reciting memorized material.    Be aware of errors in syllable- and word structure and take measures of articulatory rate.   Some clutterers have phoneme-specific misarticulations.  Most clutterers exhibit reduced (non-phoneme-specific) speech intelligibility as the talk becomes more informal and extended.  Speech intelligibility arises from elisions of sounds and syllables, neutralization of vowels, cluster reductions.

  • Ask the client to count backwards: 100-97-94-91….
  • Ask the client to count from 20 to 29
  • Older clutterers should read some words that are difficult to pronounce (e.g., “statistical,”  “chrysanthemum,” “possibilities,”  “tyrannosaurus”) and produce these words three times in succession first at their comfortable rate and then at a faster speech rate.
  • Older clutterers should read some words with changing stress pattern sequences such as "apply, application, applicable" (a_ply’ / a_pli_ca’_tion / a_pli’_ca_ble).

OMAS (Riley and Riley, 1985): Although the norms for adolescents and adults are lacking, the diadochokinetic tasks of the oral motor assessment scale (OMAS) provide clear guidelines for observation of oral motor coordination. 

Imitation of numbers (forward and backward) provides information of auditory memory and flexibility.



People who clutter commonly experience language deficits besides their articulatory problems. It is, therefore,  important to assess the language skills of the client.   Language difficulties include word-finding problems, poor syntactic structure, lack of coherence and cohesion in discourse and narratives, and compromised pragmatics (e.g., poor presuppositional skills such as not taking into account the listener’s viewpoint or knowledge; frequent interruption of conversational partner’s turn) in individuals who clutter.   We speculate that a number of the clutterer’s disfluencies are motivated by linguistic rather than motoric difficulties; these disfluencies are often called “linguistic maze” behaviors.

  • Ask the client to retell a story you told them. Observe the following as the client retells you the story:  ability to paraphrase the story with the major points of the narrative in logical sequence, and with  intact story grammar,  maintaining syllable-, word- and sentence structure, appropriate pausing, adequate speech intelligibility, appropriate pragmatics.

  • Imitation of sentences of increasing length (up to 20 word-sentences) for adults and adolescents.  This task  provides information on auditory memory skills and on the amount of language complexity the client can handle.


Computer-based Cluttering Assessment Tool

Because of the multidimensional nature of cluttering, we need to supplement assessment of the individual dimensions such as rate and fluency with a means to rate the overall severity of cluttering based on the trained clinician perception.  A freeware assessment tool was developed for this purpose by Klaas Bakker, the Cluttering Assessment Program (CLASP). It is available from the Resources and Links section of this website.


This assessment tool allows the clinician to determine % talking time cluttered. While listening to a speech sample, talking time is measured by pressing the left mouse of the computer when there speech is perceived (either fluent or cluttered). The perception of cluttering is marked by holding down the right mouse for the duration of perceived cluttering. More information about the program is available from the download site.



Cluttering checklists and self-assessment

  • Predictive Cluttering Inventory (Daly and Cantrell, 2006), also translated in Dutch (by van Zaalen, 2007) and in German (by Abbink, 2007).
  • Checklist of Cluttering Behaviours (Ward, 2006)
  • The Perceptions of Stuttering Inventory (Woolfe, 1967)
  • WASSP (Wright and Ayre, 2000)
  • The S-24 (Andrews and Cutler, 1974)

Where there are questions relating to cluttering behaviors (for example, some questions on the WASSP and PSI relate to the physical aspects of disfluencies),  comparisons can be made between the clinician’s observations and those of the  client.  For instruments tapping feelings and attitudes (such as the S-24, subsections of the WASSP and the “expectancy“ and “avoidance” statements on the PSI), the clinician can go through the responses together with the client once the client has completed the assessment and use the client’s responses as springboard for subsequent therapy.

  • Ask the client to critique his own speech during various recorded tasks, compared to the clinician’s critique.   A 5-point rating scale is often useful to judge the recorded samples on each of the major dimensions of the client’s speech and language.



Writing and reading are higher developmental stages of speech and  language development. Besides linguistic weaknesses, poor handwriting is one of the earlier behaviours associated with cluttering.  Some older clutterers use the compensatory strategy of printing the written code.  It is suggested that clients be asked to write in both script as well as print for comparison. Writing errors may mimic difficulties in the speech domain, so ask the client to write a short paragraph, looking for untidy or illegible writing, weak spelling, poorly constructed grammar, and transposition and omissions of letters as evidence of cluttering related behaviors.


Differential diagnostics with other disorders

Cluttering usually co-exists with other disorders such as stuttering, articulation disorders, attention-deficit disorders/hyperactivity disorders and learning disabilities.

The available literature as a whole suggests that an essential difference between cluttering and stuttering lies on the speaker’s level of preparedness for saying intended utterances. Stutterers know what they intend to say but are interfered at the motoric level in their attempts to produce various words, whereas clutterers do not necessarily know all of what they want to say (or how to say it) but continue talking anyway. Part-word repetitions, prolongations  and blocks are typically produced by stutterers, whereas excessive but normal disfluencies often characterize the speech of clutterers. Thelatter include interjections, incomplete phrases/words, revisions.

Persons who clutter exceed the normal qualitative and quantitative limits of changes in phonemes and tend to delete or neutralize syllables that standard speakers do not neutralize, especially in fast speech. Although symptoms of ADD/ADHD  are mentioned as cluttering, individuals diagnosed with ADHD do not necessarily clutter.

Specific Learning Difficulties have been reported to co-exist with cluttering, especially difficulties in oral expression, reading, writing, handwriting and music;however, corroborating data for these observations are anecdotal.



Analyze the recordings and questionaires and decide on rate, fluency, articulation, language and cognitive/emotional components of the disorder. Comparing the client’s perspective with the clinician’s perspective can enlighten the clinician regarding the client’s self-awareness of the disorder.

Rate:                                Mean articulatory rate in SPS (for consecutive minutes) during reading and retelling a memorized story; rating of the degree or irregularity in speech output (i.e., whether the pauses coincide with phrase or clause boundaries)

Fluency:                           Stuttering Severity Index, % normal disfluencies, % stutter-like disfluencies, proportion normal/stutter disfluencies

Articulation:                      Accuracy of syllable and word structure; appropriate stress patterns, speech naturalness (using appropriate prosody), overall speech intelligibility.

Language:                        Word, sentence and story structure; cohesions and

coherence of narratives, pragmatics

Cognitive and emotional: Feelings and attitudes towards communication; self-awareness of one’s speech and language behaviors.

Perspective:                     Comparison of results of speech tasks and clinician’s perceptions on various  checklists with the client’s perception of his communication behaviors.




The following is the most recently revised version of the working definition of cluttering (St.Louis, Raphael, Myers and Bakker, 2007). This definition reflects our best collective judgment of what cluttering is, but will be further modified when and if data indicate a need to do so:


Cluttering is a fluency disorder characterized by a rate that is perceived to be abnormally rapid, irregular or both for the speaker (although measured syllable rates may not exceed normal limits). These rate abnormalities further are manifest in one or more of the folowing symptoms:

a)    an excessive number of disfluencies, the majority of which are not typical of people who stutter

b)    the frequent placement of pauses and use of prosodic patterns that do not conform to syntactic and semantic constraints; and

c)    inappropriate (usually excessive) degrees of coarticulaion among sounds, especially in multisyllabic words.


*The assessment procedures outlined above are offered as guidelines, subject to modifications as warranted by empirical data based on research.



Please send reactions or questions to: cluttering@vanzaalen.nl