Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12625000725460p
Ethics application status
Submitted, not yet approved
Date submitted
9/06/2025
Date registered
8/07/2025
Date last updated
8/07/2025
Date data sharing statement initially provided
8/07/2025
Type of registration
Prospectively registered

Titles & IDs
Public title
Acquired stuttering: Exploring behavioural characteristics, response to treatment, and brain changes associated with stuttering.
Scientific title
Acquired stuttering: Exploring behavioural characteristics, response to treatment, and brain changes associated with stuttering in previously fluent speakers aged 5 and above.
Secondary ID [1] 314545 0
Nil known
Universal Trial Number (UTN)
U111-1323-4107
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Stuttering 337645 0
Condition category
Condition code
Physical Medicine / Rehabilitation 333971 333971 0 0
Speech therapy

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Arm 1: Comprehensive Behavioural Assessment.
Arm 1 has a duration of up to 12 months. Participants will complete three 3-hour assessments over 6-12 months (9 hours total), to explore longitudinal presentation of behavioural characteristics associated with acquired stuttering. Each assessment block will be completed over 2-3 sessions (ideally within a week) with each session lasting no longer than an hour. Assessment will occur at the University of Canterbury Speech and Hearing Clinic or online, and will be administered by qualified Speech-Language Therapists.
During assessment, participants will complete a comprehensive case history. Permission will be sought to review medical records (relating to stuttering) and any existing brain images. Clinical speech and language assessments, questionnaires, and observations will evaluate language, speech, cognitive and motor function (as relevant to individual presentation), alongside a thorough assessment of speech fluency.
All formal assessments used in the study are published (e.g. Boston Naming Test, Communication Participation Item Bank, Montreal Cognitive Assessment), and are standard practice for speech therapists. Speech fluency will be assessed during conversation, picture description and paragraph reading tasks. Assessments will be completed by qualified members of the study team. Assessment will be individualised depending on the presenting characteristics (e.g. age, underlying neurological condition) of the participant.

Arm 2: Systematic Behavioural Treatment for Acquired Stuttering
Arm 2 occurs between the first and second assessments in Arm 1. The duration of Arm 2 will be participant-dependent, but is expected to be 2-6 months for most participants. Participants who have completed the initial assessment in Arm 1 and a) have more than 3% stuttered disfluencies and/or b) have concerns about their speech fluency, can choose to receive systematic speech therapy treatment. The aim of the treatment is to limit the impact and severity of the stutter, by helping participants to increase speech fluency, optimise communication, address negative feelings and emotions, and accept any residual fluency disruption. Adherence will be assessed by treatment attendance. Prior to treatment, participants will be asked to complete 1-2 additional assessment sessions (of up to 1 hour) to establish speech fluency baseline. Treatment sessions include the following:
a) Discussion of communication successes and challenges
b) Assessment of fluency in conversation, picture description and reading tasks
c) Practice of fluency modification techniques.
Following treatment, participants will complete 2 assessment sessions to monitor treatment effects (Assessment blocks 2 and 3 from Arm 1).
Treatment dosage and schedules will be individualised based on presentation and needs. Participants will receive from 1-30 hours speech therapy. Each session will last no longer than 1 hour. Treatment will be provided at the University of Canterbury Speech and Hearing Clinic or online, by qualified speech therapists. All fluency modification techniques used are standard practice in speech therapy (e.g. rhythmic speech, easy-onset), and will be selected based on individual response to trials of different strategies. Adherence will be assessed by monitoring treatment session attendance.

Arm 3: Neuroimaging (MRI) study
Arm 3 occurs concurrently with Arm 1 and Arm 2, over a 12 month period. A subset of participants from arm 1 and arm 2 will be offered one or more MRI scans. Participants will be randomly selected from Arm 1 and Arm 2 depending on clinical presentation and research need. Scanning will take place at Pacific Radiology, St George's Hospital, in Christchurch. Each scan will take approximately 1 hour and will be conducted by qualified MRI technicians, with results reported by a specialist radiologist. Participants will complete both structural and functional research scans, following our lab's established MRI protocol for studies in stuttering.
Participants selected from Arm 1 may complete 1–2 scans, associated with the initial assessment and, if applicable, a follow-up assessment. Participants from Arm 2 may complete 2–3 scans: a pre-treatment scan (which may be the initial assessment scan from Study 1), a post-treatment scan, and, if applicable, a follow-up scan.
Intervention code [1] 331172 0
Rehabilitation
Intervention code [2] 331286 0
Behaviour
Comparator / control treatment
Participants act as their own control, with pre- and post-treatment assessment used to evaluate treatment effects.
Control group
Active

Outcomes
Primary outcome [1] 341628 0
Change in Stuttering Severity
Timepoint [1] 341628 0
Arm 1: assessed at assessment block 1 (baseline: commencement of Arm 1), block 2 (6 months post commencement), and block 3 (primary timepoint: 9-12 months post commencement). Arm 2: assessed at baseline assessment sessions 1 (Baseline from Arm 1) & 2 (2-4 weeks post baseline); 1 week following final treatment session (primary timepoint); and 3 months and 6 months following final treatment session (equivalent to assessment blocks 2 and 3 of Arm 1).
Primary outcome [2] 341922 0
Change in Communicative Participation and Quality of Life (composite outcome)
Timepoint [2] 341922 0
Arm 1: assessed at assessment block 1 (baseline: commencement of Arm 1), block 2 (6 months post commencement), and block 3 (primary timepoint: 9-12 months post commencement). Arm 2: assessed at baseline assessment sessions 1 (Baseline from Arm 1) & 2 (2-4 weeks post baseline); 1 week following final treatment session (primary timepoint); and 3 months and 6 months following final treatment session (equivalent to assessment blocks 2 and 3 of Arm 1).
Secondary outcome [1] 448136 0
Changes in Stuttering Severity across Treatment Sessions (Arm 2 only)
Timepoint [1] 448136 0
Arm 2 nnly: SS1-4 and WSI - Every treatment session OASES and/or TOCS-ORS: Weekly during treatment block(s)
Secondary outcome [2] 448784 0
Brain changes associated with stuttering occurance
Timepoint [2] 448784 0
Assessed for Arm 1 only. Baseline (beginning of Arm 1 OR existing research or clinical MRI scans) 12 months post-commencement of Arm 1
Secondary outcome [3] 449018 0
Brain changes associated with stuttering treatment
Timepoint [3] 449018 0
Assessed for Arm 2 Only. Within 1 month of final treatment session of Arm 2 (participant-dependent, approximately 3-6 months post-commencement of Arm 2)
Secondary outcome [4] 449021 0
Fatigue
Timepoint [4] 449021 0
Arm 1: assessed at assessment block 1 (baseline: commencement of Arm 1), block 2 (6 months post commencement), and block 3 (primary timepoint: 9-12 months post commencement). Arm 2: assessed at baseline assessment sessions 1 (Baseline from Arm 1) & 2 (2-4 weeks post baseline); 1 week following final treatment session (primary timepoint); and 3 months and 6 months following final treatment session (equivalent to assessment blocks 2 and 3 of Arm 1).

Eligibility
Key inclusion criteria
Acquired onset of speech disfluencies - with or without known neurological event or condition.
At least 3% stuttered disfluencies in speech AND/OR reported concern about speech fluency.
Proficient in English - bi/multilingual individuals can participate.
Able to participate in assessment and treatment sessions (for Arms 1 and 2)
Able to complete an MRI scan (Arm 3 only).
Able to provide informed consent (or assent if under 16).
Minimum age
5 Years
Maximum age
No limit
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Persistent Developmental stuttering
Currently receiving treatment for stuttering

Study design
Purpose of the study
Treatment
Allocation to intervention
Non-randomised trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Other
Other design features
Participants will:
- take part in Arm 1 if they have a) an acquired on set of speech disfluency, b) more than 3% stuttered disfluencies in speech and/or c) have concerns about speech disfluency.
- take part in arm 2 if they: a) have more than 3% stuttered disfluencies and/or b) have concerns about their speech fluency, and c) choose to receive systematic speech therapy treatment.
- take part in arm 3 if they are randomly selected.
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
Up to 100 participants will take part in Arm 1 and Arm 2.
A subset of participants (around 30-50) will be included in Study 3.

Arm 1: Descriptive, within and between group comparisons. Collection of comprehensive assessment data allows for reporting of characteristics of single cases and potentially group-based comparison of different variables. We will examine the relationship between stuttering characteristics (including severity and impact) and participant characteristics, such as neuropsychological, motor, and language function test results, using appropriate correlation and regression analyses. Descriptive statistics will be used to summarise the longitudinal course of stuttering over time. Additionally, baseline data collected prior to treatment will provide a reference point for within-subject comparisons following completion of Study 2, enabling analysis of treatment outcomes.
Arm 2: Multi-baseline, single-case experimental design (SCED), with pre-/post-treatment comparisons looking at effect sizes.
Arm 3: Analysis of assessment scans to identify structural and/or functional brain changes related to stuttering. Analysis of pre-/post-treatment scans to identify functional and structural differences or changes related to stuttering treatment.

Recruitment
Recruitment status
Not yet recruiting
Date of first participant enrolment
Anticipated
1/08/2025
Actual
Date of last participant enrolment
Anticipated
31/12/2035
Actual
Date of last data collection
Anticipated
31/12/2036
Actual
Sample size
Target
100
Accrual to date
Final
Recruitment outside Australia
Country [1] 27088 0
New Zealand
State/province [1] 27088 0

Funding & Sponsors
Funding source category [1] 319093 0
University
Name [1] 319093 0
University of Canterbury
Country [1] 319093 0
New Zealand
Primary sponsor type
University
Name
University of Canterbury
Address
Country
New Zealand
Secondary sponsor category [1] 321557 0
None
Name [1] 321557 0
Address [1] 321557 0
Country [1] 321557 0

Ethics approval
Ethics application status
Submitted, not yet approved
Ethics committee name [1] 317693 0
Southern Health and Disability Ethics Committee
Ethics committee address [1] 317693 0
Ethics committee country [1] 317693 0
New Zealand
Date submitted for ethics approval [1] 317693 0
09/06/2025
Approval date [1] 317693 0
Ethics approval number [1] 317693 0

Summary
Brief summary
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 141830 0
Ms Kate Tyson
Address 141830 0
Psychology, Speech and Hearing, University of Canterbury, Arts Road, Ilam, Christchurch 8140.
Country 141830 0
New Zealand
Phone 141830 0
+64 21 107 5362
Fax 141830 0
Email 141830 0
[email protected]
Contact person for public queries
Name 141831 0
Kate Tyson
Address 141831 0
Psychology, Speech and Hearing, University of Canterbury, Arts Road, Ilam, Christchurch 8140.
Country 141831 0
New Zealand
Phone 141831 0
+64 21 107 5362
Fax 141831 0
Email 141831 0
[email protected]
Contact person for scientific queries
Name 141832 0
Catherine Theys
Address 141832 0
Speech-Language Neuroscience Lab, University of Canterbury, Arts Road, Ilam, Christchurch 8140.
Country 141832 0
New Zealand
Phone 141832 0
+64 3 3694516
Fax 141832 0
Email 141832 0
[email protected]

Data sharing statement
Will the study consider sharing individual participant data?
Yes
Will there be any conditions when requesting access to individual participant data?
Persons/groups eligible to request access:
• Researchers
Conditions for requesting access:
• Yes, conditions apply:
• Requires review on a case-by-case basis by the trial custodian, sponsor or data sharing committee
• Requires a scientifically sound proposal or protocol
• Requires approval by an ethics committee
• Requires a data sharing agreement between data requester and trial custodian or sponsor
What individual participant data might be shared?
• De-identified individual participant data:
• Published results
What types of analyses could be done with individual participant data?
• Systematic reviews and meta-analyses
• Studies testing whether findings can be repeated or confirmed
When can requests for individual participant data be made (start and end dates)?
From:
After publication of main results
To:
A finite period of: 10 years
Where can requests to access individual participant data be made, or data be obtained directly?
• Email of trial custodian, sponsor or committee: [email protected]

Are there extra considerations when requesting access to individual participant data?
Yes: Maori consultation required before sharing of Maori participant data. Pacific consultation required before sharing of Pacific people's data.



What supporting documents are/will be available?

No Supporting Document Provided


Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.