Purpose Childhood apraxia of speech (CAS), a motor-based speech disorder, has been well studied in English contexts. However, there is a limited understanding of the applicability of its features to other languages. Thus, this study sought to determine the applicability of the features identified in the English CAS literature to Cantonese CAS. Method A two-round modified Delphi survey of experts was used to identify the clinical features of CAS in Cantonese speakers. Ten Cantonese-speaking qualified speech therapists were recruited as experts. In Round 1, the experts were asked an open-ended question about the clinical features of Cantonese CAS. In Round 2, the experts were asked to rate the importance of the proposed clinical features for making differential diagnoses of Cantonese CAS on a 5-point Likert scale ranging from 1 ( very important ) to 5 ( not important at all ). Results In Round 1, the expert panel identified 79 clinical features in nine domains. Sixty-two features (78.5%) were consistent with English CAS. Three English features were not identified in this study, while three features specifically related to Cantonese phonology were identified. In Round 2, 29 clinical features across six domains were found to meet the statistical criteria and were therefore regarded as important for making differential diagnoses of CAS among Cantonese speakers. Conclusions The results suggest that the clinical features identified in the English CAS literature are applicable to Cantonese CAS. The consistency of the findings implies that core and possible co-occurring features are shared between English and Cantonese CAS. The six features that were not common in both languages were discussed. Further investigation of CAS in and between different languages is recommended. This study is not the end point. Future studies can empirically examine the lexical tones or pitch variations to develop a possible objective measure for CAS.

Introduction Pitch variation, which refers to one's ability to vary fundamental frequency (F0) within or between syllables when speaking, has not been investigated in children with childhood apraxia of speech (CAS). However, pitch variation plays an important role in tone languages, as varying F0 patterns communicate different lexical meanings. This study investigated pitch variation abilities in individuals with CAS via the tone-sequencing tasks (TSTs), focusing on task performance and the effects of syllable structure, lexical status, and tones. Method Three Cantonese-speaking children with CAS (aged 3;7–5;8 [years;months]) and six children without CAS participated in the study. Children without CAS were divided into two control groups, comprising those with speech and/or language impairment or typical development. TSTs consisted of 56 sets of five repetitions of stimuli. The stimuli varied in syllable structure, lexical status, and tones. Percentage of tones correct (PTC), consistency scores, F0 values, and acoustic repetition duration were measured. Results The CAS group performed more poorly than the control groups on the TST with respect to tone accuracy, consistency, and repetition duration. No interaction effects between group and syllable structure or group and lexical status were found. No significant difference was found on F0 values across time between Tone 1 and Tone 2 syllables in the CAS group. However, interaction effects between group and time points of F0 values on Tone 2 syllables were found. Discussion The results suggest that children with CAS have difficulty with pitch variation, which was revealed on the TST with respect to tone accuracy, consistency, and repetition duration. Moreover, children with CAS have difficulty in varying F0 values to produce high-rising tones and tend to use high-level tones to substitute. Clinically, the TST may be useful to assist in the diagnosis of CAS. Isolated vowel stimuli may be useful to test young children or children with severe impairment. Future investigations and development of a normed tool for children with CAS are suggested.

Introduction: Childhood apraxia of speech (CAS) is a paediatric motor speech disorder. We investigated the lexical tone perception and production abilities of children with CAS and the relationships between the two. Methods: Three children with CAS, aged between 3;7 and 5;8, were given the Cantonese Tone Identification Test (CANTIT) and the Hong Kong Cantonese Articulation Test (HKCAT) for assessment of tone perception and production, respectively. Accuracy and error patterns were investigated based on their performance on the two tests. Correlation analysis was performed on children's perception and production scores. Results: Two children scored at the lowest rank on the CANTIT, while one child obtained a Z score of 0. All children scored three standard deviations below the mean on the HKCAT. No statistical differences were found among the six tones with respect to perception accuracy, H(5) = 3.731, p = 0.589. Error analysis showed that children with CAS demonstrated more confusion on perceiving tones compared with TD peers. There were no main effects for task (F(1,2) = 0.040, p = 0.859) or tone (F(5,10 = 0.997, p = 0.467); nor were there task or tone interaction effects on perception versus production accuracy (F(5,10) = 1.772, p = 0.206). Tone perception and production accuracy were not significantly correlated (r 2 = 0.181, p = 0.078). Discussion: Tone perception deficits were evident in two out of three children with CAS, while all children had lexical tone production difficulties. In this small sample, tone production was more universally affected than tone perception.

Purpose: Apraxia of speech (AOS) and childhood apraxia of speech (CAS) are motor-based speech disorders that have been well studied in Indo-European languages. There is limited understanding of these disorders in speakers of Sino-Tibetan languages, such as Chinese. The purpose of this study is to review methods used in research studies for the assessment and diagnosis of AOS and CAS in Chinese speakers. Method: This scoping review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews guidelines. Articles with a focus on AOS or CAS in Chinese speakers were systematically searched in seven English and six Chinese databases. Three reviewers performed independent screening, data extraction, and quality assessment after obtaining 100% agreement on the prescreening exercise. A qualitative analysis was conducted to rate the quality of diagnoses, ranging from high (Level I) to low (Level III), with Level IV assigned to studies for which the appropriate rating was unclear due to insufficient evidence. Results: Twenty-eight AOS articles and five CAS articles were identified. A variety of assessment and diagnostic methods were reported. No study of Chinese speakers with AOS or CAS received a rating of Level I. The highest level achieved was Level IIIa for both AOS and CAS studies. Conclusions: There is no reliable and valid test or method for the diagnosis of AOS or CAS in Chinese speakers. The current gold standard of diagnosis is based upon expert perceptual judgment. Further single-language and cross-linguistic investigations of AOS and CAS and the future development of assessment and diagnostic methods are recommended.

Background A survey study on clinical practice not only provides insight into the implementation of knowledge, but also informs future investigations. There is a limited understanding of childhood apraxia of speech (CAS) in Cantonese speakers. This study examined the clinical practice of CAS in Hong Kong and discussed future directions of research for better evidence-based practice. Methods Qualified Hong Kong pediatric speech-language pathologists (SLPs) completed the online questionnaire, which had a total of 48 questions regarding their knowledge of and experience with CAS in Cantonese speakers, including assessment, diagnosis, and treatment. Results Seventy-seven responses were received from Hong Kong SLPs. Most of the SLPs (83.2%) rated their understanding of CAS as either “a little” or “fair”. About half (53.2%) of the respondents had worked with children with CAS. No standardized assessment or objective/quantitative measures were used clinically. Instead, seven assessment tasks, including imitation of polysyllabic words and speech and language samples were used commonly. Perceptual judgment of clinical features is still the most popular approach for diagnosis, with a variety of lists in use. Of concern was that, in addition to using some evidence-based approaches, local SLPs treated CAS using approaches that have limited evidence, in the context of less treatment frequency, targeting both speech and language skills within the same session, and with only partial implementation of the approaches. Conclusions The results suggest that the understanding of CAS among local SLPs requires attention. One reason for this is that evidence regarding the assessment, diagnosis, and treatment of Cantonese speakers with CAS is still limited. Future investigations are needed.