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Professor TO, Carol K. S.

Professor TO, Carol K. S.


Research Professor (Adjunct) Charles Sturt University, Australia

Associate Professor

Academic Unit of Human Communication, Learning, and Development


Postgrad Diploma in Epidemiology & Biostatistics (CUHK)


[javascript protected email address]


(852) 3917 1591


Room 760, Meng Wah Complex

Research Expertise

  • Autism Spectrum Disorders
  • Child Development
  • Chinese Language and Literature Education
  • Communication Sciences and Disorders
  • Speech and Hearing Sciences

Prospective PhD/ EdD/ MPhil Applications

I am available to supervise PhD/MPhil students and would welcome enquiries for supervision.

Speech and Language Development and Disorders in Children

Communication in Autism


Teaching Areas

SHSC3031 Speech Sound Disorders

SHSC3035 Pediatric Complex Cases 


Honors & Awards

2017 Outstanding Mentor Award (for Employees with Autism) Labour and Welfare Bureau, HKSAR Government


2016 Innovative Award for Inclusive Organization, Labour and Welfare Bureau, HKSAR Government


2015 Faculty Knowledge Exchange Award, The University of Hong Kong


2013 Faculty Outstanding Young Researcher Award, The University of Hong Kong

2010 Faculty Early Career Research Output Award, The University of Hong Kong



Editorial Board Membership of Scholarly Journals

2016 – Present: Member of Editorial Board, Bilingualism: Language and Cognition


2012 – Present: Member of Editorial Board, Speech, Language and Hearing


External Funds

Co-Principal Investigator Using Advanced Neuroimaging to Predict Language and Cognitive Outcomes in Pre-Term Infants, Collaborative Research Fund (CRF) 2019-2020, Hong Kong Research Grants Council, (HK$5,559,743) (Project Coordinator: Prof. Patrick Wong, CUHK)
Principal Investigator, Predictors of the efficacy of a parent-implemented language facilitation program for children with autism spectrum disorders". Health and Medical Research Fund (HMRF) 2017; Food and Health Bureau (FHB) (Project No.: 16172071) (HK$1,160,001). 
Principal Investigator, "Speaking Your Language" - An Investigation of Cantonese Child Directed Speech by South Asian, Immigrant Chinese, and Local Hong Kong Mothers 都會講廣東話” - 探討南亞裔、地來港及本地母親使用廣東話於幼兒導向話語的情況Research and Development Projects 2018-2019 of the Standing Committee of Language Education and Research (SCOLAR); Education Bureau, HKSAR (Co-Investigators: Prof. Alan YU and Dr. Yao YAO). (Project No.: EDB(LE)/P&R/EL/175/17) (HK$3,014,784).


Principal Investigator, Using Differential Response-to-Treatment to Inform Diagnosis of CAS - Evidence from Chinese 利用治療效果差異決定兒童期失用症的診斷 - 漢語兒童的證據. General Research Fund for 2017/2018. (Project No.: 17614717) (HK$791,290)
Principal Investigator, Investigating Prognosis and Risk Factors of Speech Sound Disorder: A Natural History Study using A Survival Analysis Approach 利用存活分析調查構音問題的自然史 – 預後及誘發因素的研究. General Research Fund for 2014/2015 (HK$702,002).
Principal Investigator, Evaluating Treatment Efficacy of Two Syntactic Treatment Procedures for Children with Specific Language Impairment (SLI): A Randomized Controlled Trial. 兩項語法訓練模式對語言障礙學童療效之研究. General Research Fund for 2010/2011 (HK$844,000)
Principal Investigator, Assessing Theory of Mind (ToM) in Chinese Children with Autism Spectrum Disorders, 漢語兒童心智解讀發展. General Research Fund for 2009/2010 (HK$730,810)
Project Coordinator, Promoting Employment for Adults with High-Functioning Autism in Hong Kong - Advocacy and DIssemination, Commmunity Participation Funding Programme on Equal Opportunities 2015/2016. Equal Opportunities Commission.
Co-Investigator, Development of a Mandarin Speech Perception Battery, General Research Fund for 2018/2019 ($473,822) (Principal Investigator: Prof. Lena Wong).
Co-Investigator, Re-visiting tone acquisition of Cantonese speaking children in Hong Kong, General Research Fund for 2015/2016. (Principal Investigator: Dr. Peggy Mok, CUHK).
Co-Investigator, An ultrasound investigation of the acquisition of speech articulation in Cantonese, Putonghua, and English, General Research Fund for 2013/2014. (Principal Investigator: Prof. Diana Archangeli, HKU).
Co-Investigator, Investigating linguistic factors associated with stuttering in Cantonese, Australian Grant Council for 2013/2014. (Principal Investigator: Prof. Ann Packman).


Internal Funds

Principal Investigator, Phonological Development: A Normative Study of Putonghua­Speaking Children. Seed Fund for Basic Research 2019/2020 (HK$97,060).

Principal Investigator, A caregiver based language intervention for toddlers who are at-risk of language delay: A feasibility Study. Seed Funding for Basic Research 2016/2017 (HK$77,570) 
Developing Students' Phonetic Transcription Skills Using a Self-Paced, Web-Based Approach to Learning. Faculty Teaching Development Fund 2015/2016 (HK$249,148).
Principal Investigator, Raising Public Acceptance of & Promoting Employment for Adults with Autism in HK. HKU 81 Inclusion Fund 2014/2015.
Principal Investigator, Pitch perception in individuals with Autism speaking a tone language. Small Project Fund 2013/2014 (HK$80,000).
Principal Investigator, Is prenatal maternal mental health problem a risk factor of SLI? Seed Funding Programme for Basic Research 2011/2012 (HK$67,590).
Principal Investigator, Effect of Using Putonghua as the Medium of Instruction on Specific Language Impaired Children with Cantonese as the mother tongue in Hong Kong. Seed Funding Programme for Basic Research 2009/2010 for New Staff (HK$111,472).
Co-Investigator: Hyperlexia in Chinese children with autism. Faculty Research Fund (25th round) 2012/2013. (Prinicipal Investigator: Dr. Ifan Su).
Co-Investigator: Word Imageability and N400 in Individuals With Autism Spectrum Disorders. Faculty Research Fund (25th round) 2012/2013. (Prinicipal Investigator: Dr. Linda Iao).

Refereed Journal Articles

* student mentee

* Ambreen, S. & To, C. K. S. (in press). Review of the phonological system of contemporay Urdu spoken in Pakistan. International Journal of Speech-Language Pathology.


*Qi, X., Zhao, C., To, C. K. S. (in press). Empowering Hong Kong Chinese families with Autism: A preliminary study of the online Hanen More Than Words Program. Autism & Developmental Language Impairments. 


Yu, A. C. L., McAllister, R., Mularoni, N. & To, C. K. S. (2024). Atypical temporal sensitivity in coarticulation in autism: Evidence from sibilant-vowel interaction in Cantonese. Journal of Autism and Developmental Disorders. 


*Qi, X., *Ng, W. W. H., *Tsang, G. H. K., & To, C. K. S. (2023). Efficacy of a self-directed video-based caregiver-implemented language programme. Folia Phoniatrica et Logopaedica.


*Gao, R., *Yuen, J. T., *Li, X. X., & To, C. K. S. (2023). Oral diadochokinetic performance on perceptual and acoustic measures for typically developing Cantonese-speaking preschool children. Journal of Speech, Language, and Hearing Research66(5), 1445-1466.


*Ambreen, S., & To, C. K. S. (2022). Development of the Urdu speech assessment test. Journal of Clinical Practice in Speech-Language Pathology, 24(3), 138-145.


To, C. K. S., McLeod, S., Law, T., & Sam, K. L. (2022). Predicting which children will normalize without intervention for speech sound disorders. Journal of Speech, Language, and Hearing Research, 65(5), 1724-1741.


*So, K. K. H. & To, C. K. S. (2022). Systematic review and meta-analysis of screening tools for language disorders. Frontiers in Pediatrics, 10, 801120.


*Lok, J. S. Y., *Qi, X., & To, C. K. S. (2021). Using the More Than Words Program with Chinese families: A case-control study. Frontiers in Communication. 


*Ambreen, S., & To, C. K. S. (2021). Phonological development in Urdu-speaking children: A systematic review. Journal of Speech, Language and Hearing Research.  


Maggu, A. R., Kager, R., To, C. K. S., Kwan, J., & Wong, P. C. M. (2021). Complexity promotes speech sound development: Evidence from meta-analysis review. Frontiers in Psychology, 12, 1331.


Leung, C., Pin, T., Siu, A., Au, A., To, C. K. S. et al. (2021) Development and pilot evaluation of the cognition domain of the Hong Kong Comprehensive Assessment Scales for Toddlers. Developmental Neurorehabilitation, 24(4), 244-255.


Lau, J., To, C. K. S., Kwan, J., Kang, X., Losh, M., Wong, P. C. M. (2020), Lifelong tone language experience does not eliminate deficits in neural encoding of pitch in Autism Spectrum Disorders. Journal of Autism and Developmental Disorders51(9), 3291-3310.


Franich, K., *Wong, H. Y., Yu, A. C. L., & To, C. K. S. (2020). Temporal coordination and prosodic structure in autism spectrum disorders: Timing across speech and non-speech motor domains. Journal of Autism and Developmental Disorders, 51(8), 2929-2949. 


Yu, A. C. L., & To, C. K. S. (2020). Atypical context-dependent speech processing in autism. Applied Psycholinguistics41(5), 1045-1059.


*Kok, E. & To, C. K. S. (2019). Revisiting the cut-off criteria of Intelligibility in Context Scale - Traditional Chinese. Language, Speech and Hearing Services in School50(4), 629-638.


*Lam, K. Y. K., & To, C. K. S. (2018). Speech sound disorders or differences: Insights from bilingual children speaking two Chinese languages. Journal of Communication Disorders, 70, 35-48. doi: 10.1016/j.jcomdis.2017.09.002


*Law, T., Packman, A., Onslow, M., To, C. K. S., Tong, M. C. F., & Lee, K. Y. S. (2018). Rhythmic speech and stuttering reduction in a syllable-timed language. Clinical linguistics & phonetics32(10), 932-949.


*Law, T. Packman, A., To, C. K. S., Lee, K. Y.-S., Tong, M. C.-F., & Onslow, M. (2018). The topography of stuttering in Cantonese. Folia Phoniatrica et aLodopaedica, 69, 110-117doi: 10.1159/000481254


*Law, T., Packman, A., Lee, K. Y.-S., To, C. K. S., Tong, M. C.-F., & Onslow, M. (2018). Lexical tone and stuttering in Cantonese. Clinical Linguistics & Phonetics, 32, 285-297. doi: 10.1080/02699206.2017.1359851


*Li, X. X., & To, C. K. S. (2018). A review of phonological development of Mandarin-speaking children. American Journal of Speech-Language Pathology, 26, 1262-1278.  doi: 10.1044/2017_AJSLP-16-0061


*Cheng, S., Lam, G. Y. H., & To, C. K. S. (2017). Pitch perception in tone language-speaking adults with and without autism spectrum disorders. i-perception. doi: 10.1177/2041669517711200


*Li, X. X., To, C. K. S., & Ng, M. L. (2017). Effects of L1 one on perception of L2 tone - A study of Mandarin tone learning by native Cantonese children. Bilingualism: Language and Cognition, 20, 549-560. doi: 10.1017/S1366728916000195


*Chan, K. K. L. & To, C. K. S. (2016). Do individuals with high-functioning autism who speak a tone language show intonation deficits? Journal of Autism and Developmental Disorders, 46, 1784-1792.  doi: 10.1007/s10803-016-2709-5


To, C. K. S., *Yim, S. Lam, G., & Iao, L. L. S. (2016). Persuasion in Chinese school age children with and without ASD. Focus on Autism and Other Developmental Disabilities, 31, 231-240. doi: 10.1177/1088357614547888


To, C. K. S., Lui, H. M., *Li, X. X., & Lam, G. Y. H. (2015). A randomized controlled trial of two syntactic treatment procedures with Cantonese-speaking school-age children with language disorders. Journal of Speech, Language, and Hearing Research, 58, 1258-1272. doi: 10.1044/2015_JSLHR-L-14-0140


*Law, C., To, C. K. S., Wong, W. Y. M., Lee, C. H. L., & Hui, L. W. O. (2015). Assessing vocabulary skills in Cantonese-speaking adolescents. Speech, Language and Hearing, 18, 219-228. doi: 10.1179/205072815Y.0000000005


To, C. K. S., McLeod, S., & Cheung, P. S. P. (2015). Phonetic variations and sound changes in Hong Kong Cantonese: Diachronic review, synchronic study, and implications for speech sound assessment. Clinical Linguistics & Phonetics, 29(5), 333-353. doi: 10.3109/02699206.2014.1003329


Antoniou, M., To, C. K. S.,  & Wong, P. C. M. (2015). The auditory cues that drive language development are language specific. Applied Psycholinguistics, 36(6), 1493-1507. doi:10.1017/SO142716414000514


*Ng, K. Y. M., To, C. K. S., & McLeod, S. (2014). Validation of the Intelligibility in Context Scale as a screening tool for preschoolers in Hong Kong. Clinical Linguistics & Phonetics, 28, 316-328.  doi: 10.3109/02699206.2013.865789


*Wong, G. K. Y., To, C. K. S., Lee, A. M., Lam, G. Y. H., & Chan, A. Y. (2013). Effect of prenatal maternal depression on early speech sound acquisition. Speech, Language, and Hearing, 16, 215-220. doi: 10.1179/2050572813Y.0000000015


*Tang, I. N. Y., To, C. K. S., & Weekes, B. S. (2013). Riddle appreciation and reading comprehension in Chinese children. Language, Speech, and Hearing Services in Schools, 44(4), 348-359. doi: 10.1044/0161-1461(2013/12-0091)


To, C. K. S., Cheung, P., & McLeod, S. (2013). The impact of demographic factors on speech sound acquisition in Hong Kong Cantonese. Clinical Linguistics & Phonetics, 27(5), 323-338. doi: 10.1017/S1366728909990551


*Li, J. P. W., Law, T., Lam, G. Y. H., & To, C. K. S., (2013). Role of sentence final particles and prosodic cues in irony comprehension in Cantonese-speaking Children with and without ASD. Clinical Linguistics & Phonetics, 27(1), 18-32. doi: 10.3109/02699206.2012.734893


To, C. K. S., Cheung, P., & McLeod, S. (2013). A population study of children's acquisition of Hong Kong Cantonese consonants, vowels, and tones. Journal of Speech, Language, and Hearing Research, 56, 103-122. doi: 10.1044/1092-4388 (2012/11-0080)


To, C. K. S., Stokes, S., Man, Y., & T’sou, B. (2013). An analysis of noun definition in Cantonese. Language and Speech, 56(1), 105-124. doi: 10.1177/0023830912440794


To, C. K. S., *Law, T., & Cheung, P. S. P. (2012). Treatment intensity in everyday clinical management of speech sound disorders in Hong Kong. International Journal of Speech-Language Pathology, 14, 462-465. doi: 10.3109/17549507.2012.688867


To, C. K. S., *Law, T., & *Li, X. X. (2012). The influence of additional language learning on first language learning in children with language disorders. International Journal of Language & Communication Disorders, 47(2), 208-216. doi:10.111/j.1460-6984.2011.00105


To, C. K. S., Cheung, H-T., Stokes, S., & T’sou, B. (2010). Narrative assessment for Cantonese-speaking children. Journal of Speech, Language, and Hearing Research, 53, 648–669. doi: 10.1044/1092-4388(2009/08-0039)


Su, I-Fan, To, C. K. S., & Weekes, B. S. (2010). Hyperlexia in a Chinese-speaking child. Procedia – Social and Behavioral Sciences, 23, 71-72. doi: 10.1016/j.sbspro.2011.09.175


Book Chapters


To, C. K. S., & Cheung, P. S. P. (in press). Cantonese speeh development. In McLeod, S. (Ed.) The Oxford handbook of speech development in languages of the world. Oxford University Press. 


Ambreen, S., & To, C. K. S. (in press). Urdu speeh development. In McLeod, S. (Ed.) The Oxford handbook of speech development in languages of the world. Oxford University Press. 


Yu, A. C. L., To, C. K. S., & Yao, Y. (2023). Child-directed speech as a potential source of phonetic precursor enhancement in sound change: Evidence from Cantonese. In Life Cycle of Language: Past, Present, and Future. Oxford University Press. 


To, C. K. S. (2015). Child language disorders in Cantonese-speaking children. In J. Patterson, & B. L. Rodriguez (Eds.) Multilingual perspectives on child language disorders. Multilingual Matters.


To, C. K. S. (2015). Developmental speech and language disorders. In J. Myers (Ed). Encyclopedia of Chinese Language and Linguistics, UK: Brill Publishers.


To, C. K. S. & Abbot, W. (2014). Speech and language screening in schools. In D. B. McPherson, & C. J. Driscoll (Eds.) School health screening systems: The complete perspective. (pp.95-115). New York: Nova Scientific Publishing.


Weekes, B.S., Su, I-F., To, C. K. S., & Ulicheva, A. (2013). Acquired dyslexia in bilingual speakers: Implications for models of oral reading. In D. Martin (Ed). Researching dyslexia in multilingual settings: diverse perspectives. Clevedon: Multilingual Matters.


To, C, K. S., & Cheung, P. S. P. (2011). Translation to practice: Assessment of children’s speech sound production in Hong Kong. In S. McLeod, & B. A. Goldstein (eds.). Multilingual aspects of speech sound disorders in children. Clevedon: Multilingual Matters.


Standardized Assessments

To, C. K. S., Lam, C. C. C., Woo, E. K. F., Cheung, P. S. P., Lam, L. L., Sheh, A. C. S., Sam, S. K. L., Lee, F. M. Y. (2020). Hong Kong Scales for Assessment of Theory of Mind (HKAToM). Hong Kong: Department of Health, Hong Kong SAR Government.  


Wong, A. M. Y., Leung, C., Ng, A. K. H., Cheung P. S. P., Siu, E. K. L., To, C. K. S., Sam, S. K.-L., Cheung, H.-T., Lo, S-K., & Lam C. C. C. (2018). Hong Kong Test of Preschool Oral Language (Cantonese) (TOPOL). Hong Kong: Department of Health, Hong Kong SAR Government. 


T’sou, B., Lee, T., Tung, P., Man, Y., Chan, A., & To, C. K. S. (2006). Hong Kong Cantonese Oral Language Assessment Scale. Hong Kong: City University of Hong Kong. ISBN: 978-962-8868-13-1.


Cheung, P., Ng, A., & To, C. K. S. (2006). Hong Kong Cantonese Articulation Test. Hong Kong: City University of Hong Kong. ISBN: 978-962-8868-14-8


Speech and Language Corpus

To., C. K. S., Yao, Y. & Yu, A. C. L. (2022). Multi-ethnic Hong Kong Cantonese Corpus (MeHKCC)




To, C. K. S., & Cheung, P. (2010). Demographic factors in relation to speech sound development in Cantonese-speaking children. Oral presentation at the Hong Kong Speech & Hearing Symposium.

Professional Committee / Membership

2014 – Present:  Executive Council Member, Asia Pacific Society for Speech, Language and Hearing.


2013 – Present: Subcommittee member, Membership Eligibility Subcommittee of Hong Kong Association of Speech Therapists.


2013 – Present: Committee Member, International Expert Panel on Multilingual Children’s Speech.


2010 – Present: International Affiliate, American Speech-Language-Hearing Association.



Keynote Speaker

2016       "What kind of Communication Training Work for Children with Autism? Towards an Evidence Based Practice" The Macau Association for the Mentally Handicapped.


Invited Speaker

2015       "Language Assessment and Intervention in Adolescents and How to Facilitate Children's Communication Development" Macao Association of Speech Therapists.


2014    "Improving Language Skills for Cantonese-speaking Adolescents with Speech and Language Impairment" Education Bureau, HKSAR Government.