Clinical Science, Intervention and

Technology, CLINTEC

Division of Speech and Language Pathology ___________________________________________________________________________________

Childhood Apraxia of Speech: a survey of knowledge and

experience in Swedish speech-language pathologists

Ann Malmenholt

Master thesis in Speech and Language Pathology

Autumn 2012

Supervisor: Anette Lohmander

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Abstract Children with Childhood Apraxia of Speech (CAS) are seen by most clinical Speech-Language Pathologists (SLPs) working with speech and language disorders. The SLP’s understanding of CAS is crucial for diagnosis and treatment, yet little is known about their knowledge and experience. In a web-based questionnaire 178 Swedish SLPs answered questions about their perception of typical speech characteristics for CAS as potential diagnostic markers by grading their own assessment skills and estimating clinical prevalence and incidence. Eight top characteristics, from a list of 17 proposed typical speech characteristics, were listed by a mean of 66% of the SLPs in the survey (range 53-86%). These characteristics were: inconsistent production, motor-programming deficits, sequencing difficulties, oro-motor deficits, vowel errors, voicing errors, consonant cluster errors and prosodic disturbance. Eighty-one percent of the SLP’s followed Ozanne’s diagnostic model by recognizing several underlying deficits as markers for the diagnosis of CAS. The mode for clinical prevalence was 5 %. Fifty-two percent stated seeing between 0 and 1 new CAS-patient per year. Fifty-nine percent of SLP’s reported feeling confident assessing and diagnosing CAS, 41 % reported feeling unsure.

Keywords: Childhood Apraxia of Speech (CAS), survey, typical speech characteristics, diagnostic markers, clinical prevalence.

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Introduction

Children with suspected Childhood Apraxia of Speech (CAS) are seen by clinical

Speech-Language Pathologists (SLPs) in Sweden as well as in many other parts

of the world. Defining criteria for this speech sound disorder continues to be

elusive, thus the search for valid and reliable diagnostic markers continues.

Different underlying defects in the fundamental processes preceding speech

production have been proposed. More recent studies have suggested

competence deficits in the area of phonemic representation ( e.g., Marquard,

Jacks & Davis, 2004; Nijland 2009) phonologic mapping (e.g., McNeill, Gillon, &

Dodd 2009) and motor programming (e.g.Marquard, Jacks & Davis, 2004;

Shriberg, Green, Campbell, McSweeny, & Scheer, 2003; Nijland, Maassen, van

der Meulen, Gabreels, Kraaimaat, & Schreuder, 2003b; Peter, & Stoel-Gammon,

2008). These suggested problem-areas may together be contributing factors

possibly explaining the deviant and divers speech production seen in children

with CAS.

The population of children with suspected CAS is limited, with reported

prevalence rates between 0.125 % to 1.3 % (Morley, 1972; Shriberg &

Kwiatkowski, 1994; Shriberg,

Aram & Kwiatkowski, 1997a). A considerably higher prevalence rate, 3,4 % to

4,3 %, was proposed by Delaney & Kent (2004) which may reflect the

difficulties to demarcate the diagnosis of CAS.

In 2002 ASHA formed an Ad Hoc Committee on Childhood Apraxia of Speech to

examine this area of practice. The technical report reviewing the research

background for CAS was completed in 2007 (ASHA, 2007a), supporting the

ASHA position statement published the same year (ASHA, 2007b). The report

led to e.g. a proposition for the definition of CAS and some consensus about

three features observed in children with suspected CAS in the literature a)

Inconsistent errors on consonants and vowels in repeated productions of

syllables or words, b) lengthened and disrupted co-articulatory transitions

between sounds and syllables, and c) inappropriate prosody, especially in the

realization of lexical or phrasal stress (p.2). Another ASHA recommendation

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was to henceforth use the term CAS - Childhood Apraxia of Speech exclusively, a

term elsewhere referred to as Speech Delay – Apraxia of Speech (SD-AOS),

Developmental Verbal Dyspraxia (DVS), Developmental Apraxia of Speech

(DAS) or Developmental Verbal Dyspraxia (DVD).

In her general information website on CAS for Parents, Velleman states that

the”…disorder is more easily defined by what it is not

“(http://people.umass.edu/velleman/cas.html). This point was also made by

Hayden (1987) arguing that the group of children exhibiting speech motor

sequencing disruptions in its purest form is present in only a small number of

children, when excluding other sensory, cognitive and language disruptions

that could result in speech movement sequencing difficulties. The search for a

set of criteria for marking CAS, continues in both research and practice.

Velleman (2011) summarizes current knowledge in her statement that CAS is

“a disorder with motoric origins and cognitive-linguistic consequences” (p.85).

One great difficulty concerning CAS research is the uncertainty whether studies

have examined the correct population, displaying core difficulties of CAS or

difficulties also seen in children with other forms of childhood speech sound

disorders.

Aiming at defining a framework for research on speech sound disorders, seven

subtypes were listed in the Speech Disorders Classification Systems- Etiology

(SDCS-E), presented by Shriberg (2010); Speech Delay- Genetic, Speech Delay-

Otitis Media with Effusion, Speech Delay-Developmental Psychosocial

Involvement, Speech Delay-Apraxia of Speech, Speech Delay-Dysarthria, Speech

Errors – Sibilants and Speech Errors - Rhotics. Shriberg’s framework focused on

typology, etiology and the impact on speech processing. The author stated that

children with CAS often are reported to have a limited amount of speech in their

case history, a behavior not typically seen in the other subtypes. They are late to

begin to talk and show deficits in praxis marked by excessive articulatory

efforts when imitating speech models in spontaneous speech.

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Several studies have investigated observations regarding key characteristics for

CAS by SLPs and parents. In a study by Forrest (2003) 75 SLPs were asked to

name up to three characteristics that they felt were necessary for a diagnosis of

DAS (henceforth referred to as CAS). Altogether 50 different characteristics

were listed and analyzed, resulting in the six most frequent criteria accounting

for 51,5% of all responses: inconsistent productions, general oro-motor

difficulties, groping, inability to imitate sounds, increased errors with increased

length, and poor sequencing of sounds.

Nijland (2009) listed the six most pronounced CAS speech characteristics

stated by treating SLP’s. The characteristics were: difficulty sequencing

articulatory movements, highly unintelligible speech, groping behavior,

suprasegmental disturbances, inconsistent speech errors and articulation

errors, in large similar to the top six characteristic reported by Forrest (2003)

but using a somewhat different terminology.

In a questionnaire asking 98 SLP’s about their clinical practice concerning

children with phonological problems the authors received information not

asked for about uncertainty in differential diagnosing children with suspected

DVD (henceforth referred to as CAS) from 54 (61%) of the answering SLPs

(Joffe & Pring, 2008). Their responses featured inconsistent production, oro-

motor problems, groping, sequencing problems, difficulty in copying sounds,

distortions of vowels and a history of feeding and drinking problems as

potential markers for CAS. Slow progress in therapy and resistance to therapy

were mentioned to be behaviors not typically seen in children with

phonological delay or disorder thus indicating CAS. In a parental survey, 201

parents of children with CAS were asked to evaluate functional characteristics

from the International Classification of Functioning, Disability, and Health –

Children and Youth version (ICF-CY), covering the disorders consequences in

daily life and the effects on medical, developmental and functional behaviors

(Teverovsky, Bickel, & Feldman, 2009). From the survey, functional

characteristics were clustered into four main factors: cognitive and learning

problems, social communication difficulties, behavioral dysregulation and other

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oral motor problems. Identifying these often co-existing problem areas could

contribute to the understanding of underlying neural dysfunction.

Ozanne (1995) followed up a claim by Guyette and Diedrich in 1981, suggesting

that characteristics of CAS are commonly seen in all children displaying any

speech disorder of unknown origin. She studied 100 children with speech

disorders of unknown origin benchmarking previously mentioned motor

planning or programming problems (Rosenbek & Wertz, 1972; Adams, 1990;

Pollock & Hall, 1991). A cluster analysis of the 18 behaviors, thought to reflect

an underlying motor-programming or motor-planning disorder, showed that

between 27-38 % exhibited difficulties with diadochokinetic tasks, had

increased errors with increased load and inconsistent productions indicating

that these characteristics are not specific for CAS alone. In a study on normal

development of speech motor control boys were less mature up to the age of 5

years (Smith & Zelaznik, 2004). The authors also observed a plateau in the

development of coordination skills between the ages of 7-12, with consistency

increasing also after 12 years of age, an important indication of the complexity

of speech motor development. The influence of increased utterance length and

complexity on speech motor performance in typically developing children (5-

year-olds) and adults has been found to result in increased errors in both

children and adults. (Maner, Smith & Grayson, 2000). This can be seen as a

support for Ozanne’s suggestion to exclude difficulties with diadochokinetic

tasks, increased errors with increased load and inconsistent productions as

diagnostic markers for CAS.

“The Ozanne diagnostic model” refers to four clusters assembling a speech-

output planning and programming model. It contains three levels: phonological

planning (cluster I), phonetic programming (cluster II-IV) and oro-motor

control (cluster II-IV). To be diagnosed with the disorder of Childhood Apraxia

of Speech, children should display deficits on all three levels.

CAS, being a rare disorder, without consensus neither on clinical, diagnostic

markers nor a straightforward body of systematic research, leaves the clinical

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SLPs puzzled. Despite the lack of fundamental consensus, SLPs assess and treat

patients with suspected CAS, constructing their own clinical understanding of

the disorder. Expanded information on the current knowledge and practice of

SLPs assessing and treating children with CAS would be valuable in order to

confirm or contradict anecdotal reports.

Aim

The aim of this paper was to survey Swedish SLPs level of knowledge and

experience about CAS. Research questions were:

How do SLPs rate their praxis and knowledge on assessing and

diagnosing children with suspected CAS?

What speech characteristics and other deficits do SLPs consider typical

in children with suspected CAS?

How common are children with suspected CAS? Estimation of

prevalence and incidence in the clinical population.

Method

A survey-questionnaire was constructed, asking quantitative and qualitative

questions about the population of children displaying the speech sound

disorder of suspected CAS. Questions targeted the SLPs background (5 items),

clinical accustomedness and theoretical knowledge regarding CAS (12 items),

estimation of own competence regarding CAS (3 items) and questions

regarding estimated prevalence and incidence in their own clinic (2 items).

Seven questions are not accounted for in this paper due to their limited interest

for the international reader and another three questions review treatment of

CAS and will be reported elsewhere.

The questionnaire was tested in a web-based pilot study. Four, clinically and

academically experienced SLPs participated. Comments from the pilot study

concerned technical issues and choice of words and were changed in the final

version.

The web-based questionnaire was sent to 289 Swedish SLPs working with pre-

and primary school-aged children during June-November 2011 asking 22

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questions (see Appendix). Email addresses were transmitted by the SLP’s head

of departments and participants from 19 of in total 21 Swedish counties

responded. The superior received one reminder if no email address lists of

SLP’s working with the targeted patient group had been provided. The

questionnaire was distributed to the listed SLPs using Google Docs Form to

ensure that answers remained anonymous.

To avoid confusion due to variations in terminology, a list of 17 characteristics

from the literature, was presented asking respondents to select as many as

suggested speech characteristics as they felt was appropriate in order to

answer the question of typical speech characteristics seen in CAS. The

distribution of these answers was ranked and categorized according to the

cluster analysis proposed by Ozanne (1995). The 17 characteristics also

included six characteristics co-occurring in children with CAS, but not included

in Ozanne’s model. These were grouped reflecting different areas of difficulties,

namely deficits in language, attention and learning skills and difficulties with

motor control.

Questions 16 and 17 asked for SLPs preconceived opinions and thoughts shared

in free space answers. The concluding summaries of these answers are more

qualitative and were processed using content analysis.

The scale used in the question on how confident SLP’s felt assessing children

with CAS (Question 20) had six scale steps, ranging from very confident to very

unsure. By simplifying the answers into a dichotomous variable

(confident/unsure) the result became straightforward.

Results

One hundred-seventy-eight clinical SLPs responded, which equals a survey

response rate of 62%. Not all questions were answered by all respondents. The

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response rate (RR) varied between different questions in the survey with a

mean-value of 87 %.

Respondents were from different clinical settings across Sweden and had a

range of clinical experience. Forty-one percent of respondents were in their

first five years of practice, 22 % had from five to ten years experience and 37%

percent more than ten years of clinical experience with preschool and primary-

school children (Question 9; RR=98%). Forty-four percent of the SLPs worked

at hospitals or public speech and language clinics, 12 % worked at university

hospitals, 24 % at habilitation centers, nine percent in special pre- and primary

schools for children with speech- and language disorders, eight percent at

private clinics and three percent in other working places (Question 4;

RR=97%).

Praxis and knowledge on assessment and diagnosis Six main assessment approaches emerged when analyzing respondents’

answers in their own words about what they considered important when

assessing children with suspected CAS (Question 17; RR=74%). The most

frequently mentioned approach (42%) was a formal perceptual analysis of the

child’s speech in combination with an oro-motor assessment, see Figure 1.

The ICD-10 diagnoses most frequently used (Question 10; RR=96%) were oral

and/or verbal apraxia (R48.2) occurring in 44 %, phonological disorder

(F80.0A) in 22 %, a combination of phonological disorder and oral motor

developmental delay (F80.0A + F80.0B) in 23 % and other ICD-10 codes in 11

% of answers.

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Figure 1: Different assessment approaches for CAS reported by Swedish SLPs (n=131).

Twenty-nine percent of the SLPs perceived CAS to be a disorder in its own right,

10 % considered the disorder to be part of or in co morbidity with another

disorder, 51 % of the SLPs experienced that some cases are clear CAS and some

are part of or in co morbidity with other disorders. The alternative: “CAS is a

consequence of another disorder” was not agreed upon by any SLP but 10 %

replied that they did not know (Question 13; RR=96%).

When asked to share observations of co-occurring difficulties seen in children

with CAS (Question 16; RR=38%) different issues were raised by respondents

using the free text answering space. Most answers were clarifications and

comments on issues covered in general, often using different terminology, in

listed typical characteristics (Question 17) and statements about typical

behaviors (Question 15). The notion of fluctuations in the ability to produce

speech during different days was added. Some SLPs observed additional co

ordination difficulties not only obstructing smoothness of articulators and body

Formal perceptual

analysis + oro-motor

assessment (42%)

Formal oro-motor

assessment (5%)

Referring patient to specialized SLPs for oro-motor assessment (11%)

Assessment of language skills

(15%)

Language and oro-motor assessment

(18%)

Own clinical assessment battery (9%)

Assessment approaches

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movements but also affecting the control of air flow, resulting in voice quality

issues.

When asked to rate their own ability as SLPs to assess children with suspected

CAS on a six scale-step scale 55 % of respondents felt unsure and 45 %

confident about diagnosing CAS (Question 20; RR=97%). A further analysis of

these figures was conducted based on the fact that only half of the SLPs

reported that they do assess and diagnose CAS (Question 10; RR=96%). It

revealed that out of the SLPs, not assigned to diagnose children with suspected

CAS, 29 % felt confident about performing CAS assessment and 71 % did not.

Among the SLPs that assessed and diagnosed CAS 59 % reported that they felt

confident and 41 % that they felt unsure.

Speech characteristics and behaviors seen in CAS

The 171 respondents selected 2-17 characteristics from a list of 17

characteristics (Question 14; RR=96%); Mode was 7.2, in total 1043 selected

characteristics. The answers were assembled in a matrix, grouped in clusters

according to Ozanne’s model (1995), see Table 1.

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Table 1: Typical characteristics of CAS in rank order from a SLP survey and categorized according to the cluster analysis proposed by Ozanne (1995).

Typical characteristics in CAS Frequency of selection of characteristics

Cluster analysis according to Ozanne (1995)

Inconsistent production 85% I

Motor-programming deficits 82% III

Sequencing difficulties 71% II

Oro-motor deficits 63% II

Vowel errors 62% I

Voicing errors 61% II

Consonant cluster deletion 54% III

Prosodic disturbance 53% IV

Phonological deficits 44%

Resonance inconsistency 36% II

Poor fine-motor skills 34%

Metathesis 23% III

Suprasegmental disturbance 19% IV

Poor gross-motor skills 12%

Language impairment 10%

Learning difficulties 5%

Attention deficits 4%

Eighty-one percent of SLPs listed typical characteristics of speech in children

with CAS representing features from all three clusters I-III, see Figure 2.

Similar distribution was found for clusters I, II and III respectively, whereas

characteristics in cluster IV were registered somewhat less frequent.

The six characteristics not included in Ozanne’s model, were grouped in four

areas of difficulties, showing that almost half of the answering SLPs

acknowledge CAS patients to display language impairment as well. Motor

difficulties, i.e. poor fine and gross motor skills, were noted by one third of the

SLPs to be a typical characteristic displayed by children with suspected CAS.

Learning difficulties and attention deficits were not reported to be typically co-

occurring.

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Figure 2.The 17 speech characteristics typical for CAS clustered using Ozanne’s model (1995) supplemented with typical co-occurring characteristics in subsets of CAS.

Statements about suggested, typical behaviors seen in children with CAS had to

be completed by the respondents (Question 15; RR=96%). In total 92 % shared

the opinion that “children with CAS make very slow progress” and 58 % felt

that “patients were resistant to therapy”. “Regressing after a treatment brake”

was an experience shared by 58 % and “persistent speech difficulties at school

age” was noted by 84 % of the SLPs. “Difficulties with reading development”

was observed by 24 % and “difficulties with writing development” by 23 % of

the SLPs.

Clinical prevalence and incidence

The mode for rated clinical prevalence was 5 % over all clinical settings in this

study (Question 12; RR=82%), range from 0-70 % (see figure 3) reflecting the

SLP’s varying patient populations depending on work settings. Thus, the mode-

90% 96% 91%

78% 81%

53% 46%

36%

5% 4%

Clustered Characteristics in CAS

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value for prevalence estimated by SLPs working at habilitation centers was

twice as high (11%).

Figure 3: Estimation of clinical prevalence of CAS by answering SLP’s

About half of the SLPS (52 %) stated seeing between 0 and 1 new patient with

suspected CAS per year in their clinic (Table 2).

Table 2: The clinical incidence of CAS estimated by SLP’s showing the rate at which new cases occur on their caseload during one year (Question 11; RR=89%).

Number new CAS patients/year

0 0.5 1 2 3 4 5 7 8 10 12 13 15 20

% Answering SLPs

2 20 30 16 11 3 4 2 2 4 1 1 3 1

Discussion

In this study broad information about clinical SLPs knowledge and experience

concerning children with suspected CAS was collected. The quantity and

distribution of SLP’s throughout the country and in different working settings

makes it likely that they together represent current clinical practice in Sweden.

We are assuming this, despite the lack of answers from two counties and lack of

data on the distribution of SLP’s working in different work settings.

The drawback to distributing the survey anonymously was that it ruled out the

possibility to remind the SLPs to participate.

2 13 7 6 2

30

4 11 1 5 11

2 3 2 1 0 1 2 3 4 5 7 10 13

15 20 25

30

50

70 Answering SLPs in % Prevalence %

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Praxis and knowledge on assessment and diagnosis

Assessment approaches differed, reflecting the absence of a reliable and specific

test for CAS in Sweden. At present SLP’s administer their own test batteries

which probably reflect their view of CAS as a disorder of primarily

phonologic/linguistic and/or motor difficulty. The same disparity is seen in the

reported ICD-10 diagnoses used, corresponding to the SLPs comprehension and

theoretical knowledge of the disorder. This probably reflects differences in SLP-

education in the field of motor speech disorders and, particular, CAS during the

past decades.

Another challenge is diagnosing children with milder symptoms, where

suspected CAS is to be differentiated from delays in phonologic development

and/or oro-motor control, a combination of diagnoses used by almost one-

fourth (23%) in this study. Perhaps the less alarming diagnose of speech- and

oro-motor delay is preferred by SLPs in milder cases of suspected CAS due to

the implications of a neurologically based diagnosis? Age is another factor

influencing and changing the manifestations of CAS in different children over

time.

About one third of SLPs in this survey viewed CAS as a defined, exclusive

disorder, but 10 % had not experienced clear cut cases of CAS. On the other

hand half of the SLPs reported that there were clear cut cases but also others,

where CAS symptoms appeared to be a part of or in co morbidity with other

disorders. This diversity of clinical experience and viewpoints on CAS reflect

the multi facetted character of the disorder and the influence of work settings

and experience.

Thanks to the anonymity sincere answers are presumed. A future challenge is

to address the 41 % of the SLPs, who assess and diagnose children with

suspected CAS, but clearly state the need for different educational measures.

One obstacle to increase clinical skills is the limited number of patients with

suspected CAS for SLPs to get experience from. This could be resolved through

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specialization of SLPs with a recognized competence in motor speech disorders,

a suggestion already made in ASHAs position statement (2007b).

Speech characteristics and behaviors seen in CAS

The ranking of typical speech characteristics in CAS without clustering in this

survey corresponded in large with other surveys (Forrest, 2003; Joffe & Pring,

2008; Nijland, 2009).

Forrest (2003) concluded that her study on diagnostic criteria was limited due

to predetermined instructions (i.e. provide up to three criteria for diagnosing

CAS). In this study the limitation was in the list of predetermined typical

characteristics for CAS (i.e. the SLPs could not specify in their own words) yet

the mode for the number of chosen characteristics was over seven, close to the

number repeatedly stated in other surveys. In this study, more than 50 % of the

SLPs listed as many as eight characteristics, with inconsistent production being

the most common (85%), also mentioned as a key feature by Rosenbek and

Wertz (1972) among others. Motor-programming deficits (82%) described as

lack of automatization of speech motor movements (i.e. a global term including

groping and voluntary vs. involuntary speech movements) (e.g., Rosenbek &

Wertz 1972; Pollack & Hall, 1991) is a feature difficult to capture in one term.

Sequencing difficulties (71%) (e.g., Rosenbek & Wertz, 1972), oro-motor

deficits (63%) (e.g., Adams, 1990; Pollack & Hall, 1991; Rosenbek & Wertz,

1972) vowel errors (62%) (e.g., Rosenbek & Wertz, 1972; Pollock & Hall,

1991), voicing errors (61%) (e.g. Yoss & Darley, 1974a), consonant cluster

deletion (54%) (e.g., Rosenbek & Wertz, 1972; Yoss & Darley, 1974a) and

prosodic disturbance (53%) (e.g., Rosenbek & Wertz, 1972; Pollack & Hall,

1991) are difficulties alerting SLP’s.

During the construction of the survey no weighting of speech characteristics

was performed. However in the analysis the 17 characteristics were distributed

into Ozannes IV clusters which resulted in similar frequencies (90-96%) for

clusters I to III. Cluster IV showed a somewhat lower frequency (78%),

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probably because cluster IV consists of only two characteristics, one being

deviant prosody and the other an anamnesis feature not asked for in this

survey, which was no history of babbling.

Other functional problems in children with clinically diagnosed CAS were listed

using the ICF-CY and focusing on problems in addition to communication

difficulties based on specific speech output (Teverovsky, Bickel & Feldman,

2009). For over half of the children with CAS in that study, parents reported

health, mental health and developmental conditions. A significant proportion of

children with CAS had involvement of other factors in both genetic and

environmental domains (Shriberg 2010). Future research in CAS would

therefore benefit from thorough descriptions of the subjects.

Clinical prevalence and incidence

The estimated clinical prevalence mode-value of 5 % reflects different work

settings, given that the highest, outlying estimates (50% and 70%) came from

clinicians working at habilitation centers. The variance of reported prevalence’s

in the literature, from 0,125% to 3,4%, (Delaney & Kent, 2004; Morley, 1972;

Shriberg & Kwiatkowski, 1994; Shriberg, Aram, & Kwiatkowski, 1997) raises

questions about descriptions and inclusion criteria in research studies and

possibly also limitations in agreement about the group of patients diagnosed

with CAS.

Clinical incidence was asked for in percent. A few SLPs misunderstood and

supplied a rough estimate of the work life total number of patients. In these

cases the percent figure was calculated, dividing the stated sum of patients

encountered with the reported years of experience as SLP seeing patients with

CAS. The overall low incidence reminds us of that CAS occupies a small portion

of the SLPs caseload; involving around half of the clinical SLPs. This in turn may

lead to a lack of confidence and knowledge within the professional society.

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Conclusion

Even though the majority (89%) of SLPs stated a need for further education

about CAS (Question 22), this study reveals that many SLPs (81%) have god

clinical skills and are alerted when several typical speech characteristics for

CAS are present in a patient. A promising finding considering that researchers

often rely on experienced clinicians for referrals of children with suspected CAS

as potential candidates for research populations. In the body of CAS literature

much effort is spent on finding diagnostic markers in order to specify the

diagnosis of CAS and distinguishing it from other subsets of speech sound

disorders (e.g., Shriberg, Aram, & Kwiatkowski, 1997b + 1997c; Velleman &

Shriberg, 1999). However, a cluster of diagnostic markers might be more

appropriate in order to differentiate these children from children with other

speech disorders.

The survey-question with lowest RR (Question 16; RR=38%) was about

observations made on co-occurring difficulties in children with CAS, asking

beyond earlier questions. Few new topics were raised given the opportunity to

answer in own words. This might positively reflect the broadness of the survey

or it could be due to the fact that this is an open question in the latter part of the

questionnaire and respondents were eager to conclude.

Using the term syndrome together with CAS might signal that the disorder has

several characteristics. Love (2000) considered descriptions of syndromes in

neurologic medicine and concluded considering CAS that “This motor

programming disability may or may not result in a rigidly consistent set of

motor, phonologic, linguistic, or neurologic signs or symptoms, and

inconsistency among symptoms should be expected as typical rather than

atypical.” (p. 92). Childhood apraxia of speech is widely agreed upon to be a

disorder of motor planning and/or motor programming. (e.g., Caruso &

Strand,1999; Hayden, 1994; Ozanne, 1995).

The Ozanne model of speech-output planning and programming could provide

a possible guideline for clinical SLP’s. While assessing children with suspected

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CAS it could be possible to cluster the overt speech characteristics reflecting

underlying deficits. Varying characteristics could still meet up to a diagnosis of

CAS if difficulties are simultaneously found in all three domains proposed by

Ozanne.

The results from this survey supports earlier findings, i.e. inconsistent

production being described as the most prominent characteristic in CAS

mentioned by 85% of the SLPs. Seven other characteristics were listed by more

than 53% of all respondents.

There was a massive agreement found among SLPs regarding clusters of typical

speech characteristics seen in CAS patients.

In future research on children with suspected CAS, an approach as supposed by

Ozanne, could reduce procedural limitations and increase validity, making

inclusion criteria of the studied population transparent and comparable, a work

started by e.g. Moriarty & Gillon (2006) and McNeill, Gillon & Dodd (2009).

Acknowledgments

This study was completed as a master’s thesis by the first author. We are

grateful to all colleagues, answering the survey and sharing their clinical

experience and showing interest in this work.

Declaration of interest: The authors report no conflicts of interest. The authors

alone are responsible for the content and writing of the paper.

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Appendix Survey-questions:

1. Where did you study to become a Speech Language Pathologist?

2. Which year did you graduate?

3. Which county are you working in?

4. What type of setting are you working in?

Hospital, university hospital, public speech and language clinic, private clinic, habilitation center, special pre- and primary school for children with speech and language disorders, other working places

5. How many SLP-colleagues seeing pre- and primary school patients do

you have at your setting?

6. Was there a lecture about CAS during your undergraduate studies?

7. Have you participated in lectures or courses after your undergraduate

studies?

8. Have you searched for information about CAS on your own?

9. For how long have you been working with pre- or primary school aged

children?

< 5 years, 5-10 years, 11-15 years, 16-20 years, >20 years 10. Do you assess and diagnose children with CAS? yes / no

If you do, what ICD-code do you use? (Choose one or multiple answers) F80.0A, F80.0A+F80.0B, R48.2, R48.2A, R48.2B, other

11. Approximately how many children displaying CAS have you met?

Space for free answer 12. Approximately how many percent of patients on your caseload do you

consider having difficulties with verbal praxis?

Space for free answer 13. I consider CAS to be…… (Choose one or multiple answers)

o a diagnosis of its own right, not necessarily coexisting with other

disorders

o part of or in co morbidity with other disorders such as SLI, ADHD,

ADD, dyslexia, Cerebral Palsy, Down’s syndrome, Rett’s syndrome

or other disorders

o as a consequence of other disorders

o I do not know

14. Typical symptoms for children displaying CAS are….. (Choose one or multiple

answers)

Inconsistent production, motor-programming deficits, sequencing difficulties, oro-motor deficits, vowel errors, voicing errors, consonant cluster deletion, prosodic disturbance, phonological deficits, resonance inconsistency, poor fine-

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motor skills, metathesis, suprasegmental disturbance, poor gross-motor skills, language impairment, learning difficulties, attention deficits

15. Children with CAS... (Choose one or multiple answers)

make very slow progress, make expected progress, are during periods almost resistant to therapy, regress after treatment brake, have persistent speech difficulties at school age, have difficulties with reading development, have difficulties with writing development

16. Co-occurring difficulties you have observed in children with CAS?

Space for free answer 17. If a child is suspected of having CAS, what do you consider to be important

during assessment?

Space for free answer 18. What do you consider to be most important when treating children with

CAS?

19. If you have any experience treating children with CAS, please share

examples of successful intervention.

20. How secure do you feel assessing children with CAS?

Very confident, confident, fairly confident, fairly unsure, unsure, very unsure 21. How secure do you feel treating children with CAS?

22. Do you consider yourself lacking competence concerning CAS?

yes / no Questions 1-3, 5-8, 18, 19 and 21 are not accounted for in the present paper!