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Trial registered on ANZCTR

Registration number
Ethics application status
Date submitted
Date registered
Date last updated
Type of registration
Prospectively registered

Titles & IDs
Public title
Intranasal Oxytocin and the exploration of eye gaze in people who stutter.
Scientific title
A randomised controlled trial to explore the effects of oxytocin/placebo on eye gaze in adults who stutter.
Secondary ID [1] 259892 0
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Stuttering 265492 0
Condition category
Condition code
Mental Health 265642 265642 0 0
Mental Health 265813 265813 0 0
Other mental health disorders

Study type
Description of intervention(s) / exposure
In a randomised controlled trial participants who stutter will be randomly assigned to receive a single administration (24 international units) of intranasal Oxytocin (Syntocinon) or a placebo nasal spray before presenting a 3 minute speech. This speech will be made to a pre-recorded audience of strangers who were trained to display positive, neutral or negative expressions.
Intervention code [1] 264317 0
Treatment: Drugs
Comparator / control treatment
Placebo matched nasal spray that contains all non-active ingredients in the absence of the active Oxytocin.
Control group

Primary outcome [1] 262435 0
Eye gaze (total fixations and total duration of fixations) towards audience members as recorded by eye tracking equipment.
Timepoint [1] 262435 0
Single session /during the procedure
Secondary outcome [1] 273772 0
Anxiety as assessed using a Subjective Units of Distress Visual Analogue Scale
Timepoint [1] 273772 0
Pre-speech task and post-speech task
Secondary outcome [2] 273773 0
Memory for faces as assessed by a 'yes'/'no' facial recognition task
Timepoint [2] 273773 0
Post-speech task

Key inclusion criteria
Male adults who stutter

Onset of stuttering before 12 years of age

No treatment for stuttering or anxiety conditions within 6 months preceding the experimental procedure
Minimum age
18 Years
Maximum age
75 Years
Can healthy volunteers participate?
Key exclusion criteria
Onset of stuttering at age 12 years or older

Onset of stuttering due to a known conversion or any other psychological disorder

Presence of a complicating disorder (e.g., developmental delay, autism, Down’s Syndrome, cerebral palsy etc.)

Currently taking ‘psychological’ medication

Severe Depression with suicidal thoughts and/ or actions

Severe Cardiovascular problems (e.g., heart disease, history of heart attacks)

Kidney Disease- (i.e., kidney stones, recurrent bladder infections, or known kidney failure)

Psychosis (i.e., bizarre beliefs that do not represent reality; sensations without any sensory input- hearing, smelling seeing, feeling things that don’t exist.

Drugs: Smoking more than 15 cigarettes a day or addicted to other illegal substances.

Sensitivity to preservatives (in particular E 216, E 218 and chlorobutanol hemihydrate)

Study design
Purpose of the study
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Recruitment will be conducted through advertisements and flyers disseminated to treatment sites and community support services for people who stutter.

Drug allocation concealed by the numbering of all containers.

Allocation randomised by compounding chemist.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Random number generation performed by computer software. Each number allocated a code letter ‘a’ or ‘b’ where a or b represents either Oxytocin or placebo. Coding developed by an independent pharmacist.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?

Intervention assignment
Other design features
Phase 2
Type of endpoint(s)
Statistical methods / analysis

Recruitment status
Not yet recruiting
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment in Australia
Recruitment state(s)

Funding & Sponsors
Funding source category [1] 264777 0
Government body
Name [1] 264777 0
National Health and Medical Research Council
Address [1] 264777 0
GPO Box 1421
Canberra, ACT 2061
Country [1] 264777 0
Primary sponsor type
University of Sydney
University of Sydney
Sydney, NSW 2006
Secondary sponsor category [1] 263894 0
Name [1] 263894 0
Address [1] 263894 0
Country [1] 263894 0

Ethics approval
Ethics application status
Ethics committee name [1] 266757 0
University of Sydney Human Research Ethics Committee
Ethics committee address [1] 266757 0
Human Research Ethics Committee
Level 6, Jane Foss Russell Building G02
University of Sydney
Darlington, NSW 2006
Ethics committee country [1] 266757 0
Date submitted for ethics approval [1] 266757 0
Approval date [1] 266757 0
Ethics approval number [1] 266757 0

Brief summary
The goal of this study is to examine the effect of Oxytocin (OT) in facilitating eye gaze during a speaking task in adults who stutter. Participants who stutter will be randomized to receive 24UI intranasal OT or placebo before giving a speech to a pre-recorded audience. The aim of the procedure is to assess whether participants who receive OT before delivering the speech show a difference in eye gaze than the placebo group. It is predicted that the experimental participants who receive OT will demonstrate increased gaze towards audience members compared with the participants in the placebo group and thus increase access to important social information from the interaction. Secondly the experimental group is hypothesized to report less fear and anxiety following the procedure than the placebo group.
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 32418 0
Address 32418 0
Country 32418 0
Phone 32418 0
Fax 32418 0
Email 32418 0
Contact person for public queries
Name 15665 0
Mark Bayliss
Address 15665 0
Australian Stuttering Research Centre
PO Box 170
Lidcombe, NSW 1825
Country 15665 0
Phone 15665 0
+61 404 482 356
Fax 15665 0
Email 15665 0
Contact person for scientific queries
Name 6593 0
Adam Guastella
Address 6593 0
Brain and Mind Research Institute
94 Mallett St
Camperdown, NSW 2050
Country 6593 0
Phone 6593 0
+61 2 9351 0539
Fax 6593 0
+61 2 9351 0855
Email 6593 0

No information has been provided regarding IPD availability
Summary results
No Results