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Trial registered on ANZCTR


Registration number
ACTRN12623000981628
Ethics application status
Approved
Date submitted
23/08/2023
Date registered
8/09/2023
Date last updated
1/09/2024
Date data sharing statement initially provided
8/09/2023
Type of registration
Prospectively registered

Titles & IDs
Public title
What strategies help reduce Australian adults’ beliefs in COVID-19 vaccine misinformation?
Scientific title
Testing the effectiveness of revealing misleading techniques and the untrustworthiness of sources to reduce beliefs in COVID-19 vaccine misinformation in Australian adults: A randomised controlled trial
Secondary ID [1] 310448 0
Nil
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
COVID-19 vaccine 331230 0
Health literacy 331330 0
Condition category
Condition code
Infection 327990 327990 0 0
Other infectious diseases
Public Health 327991 327991 0 0
Other public health

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
The intervention is a short piece of written material addressing misinformation about COVID-19 vaccines and fertility. The written material was designed specifically for this study. The intervention will be delivered as part of an online experiment over the internet.
After answering some questions about themselves, participants will be asked to read written information on their computer or phone screen. Participants will receive a single written intervention according to their randomised group. There will be a control group and 3 intervention groups.
- The control message will provide correct information about COVID-19 vaccines and fertility.
- Intervention 1 will provide correct information + information on misleading techniques. The misleading technique that the intervention provides information about is called "cherry-picking". This is where people who spread the false claim that COVID-19 vaccines cause infertility focus on some of the facts, and ignore other facts that don’t support the false claim.
- Intervention 2 will provide correct information + information on untrustworthy sources. The information on untrustworthy sources focuses on what makes an information source lack credibility or trustworthiness.
- Intervention 3 will provide correct information + information on misleading techniques + information on untrustworthy sources.

We will require participants to view the intervention text for a minimum length of time, calculated at 100 milliseconds per word.
Intervention code [1] 326845 0
Behaviour
Comparator / control treatment
The control treatment will be written text that provides correct information on COVID-19 vaccines and fertility.
Control group
Active

Outcomes
Primary outcome [1] 335848 0
The primary outcome is the mean agreement with misinformation after the intervention. We will ask participants to respond to 6 items measuring the extent to which they agree with the misinformation (COVID-19 vaccines can cause infertility). For each item, the participants will be asked to report how much they agree with the statements using a 10 point scale, where 1 stands for Strongly Disagree (1) and 10 stands for Strongly Agree (10). We will then calculate each participant’s mean (SD) response to the six items to calculate an overall response.
Timepoint [1] 335848 0
At baseline, immediately before receiving the intervention (covariate).
Immediately after receiving the intervention (primary outcome)

Secondary outcome [1] 425875 0
Mean intention to vaccinate after the intervention. We will measure future intention to vaccinate with three items. For each item, we will ask the participants to report how much they agree with the three statements using a 10 point scale, where 1 stands for Strongly Disagree (1) and 10 stands for Strongly Agree (10). We will then calculate each participant’s mean (SD) response to the three items to calculate an overall response.
Timepoint [1] 425875 0
We will ask participants to respond to the secondary outcome measure immediately after receiving the intervention.

Eligibility
Key inclusion criteria
Australian adults (>=18 years)

who have concerns about serious side effects of COVID-19 vaccines

who provide digital consent.
Minimum age
18 Years
Maximum age
No limit
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
Are not concerned about serious side effects of COVID-19 vaccines

Study design
Purpose of the study
Educational / counselling / training
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
central randomisation by computer
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
computerised sequence generation
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s


The people analysing the results/data
Intervention assignment
Factorial
Other design features
Phase
Not Applicable
Type of endpoint/s
Statistical methods / analysis
Analysis approach: The study is a prospective, 2x2 factorial randomized controlled trial with two factors: with or without information on misleading techniques and/or information on untrustworthy sources. The aim of the study is to evaluate the interventions against a control group in terms of their effectiveness on agreement with misinformation. We will assess outcome measures after the intervention, as well as at baseline (as covariates). We will investigate whether each factor is effective on its own compared to the control. We will also examine the interaction between both factors.

Analysis of the primary outcome variable (agreement with misinformation) will use a linear model with predictors of randomised treatment (information on untrustworthy sources (No/Yes), information on misleading techniques (No/Yes)) and their interaction, adjusted for baseline level of agreement with misinformation. If there is no evidence of interaction (P-value>0.05), then a main effects model will be fitted. If evidence of interaction is seen, then separate models for each level of information on untrustworthy sources will be used to assess the effect of information on misleading techniques, adjusted for baseline level of agreement with misinformation. Analysis of secondary outcomes will use similar methods, using linear models for continuous outcomes and logistic regression for binary outcomes.

Sample size estimation: We intend to obtain data from approximately 1000 participants. A study with 4 groups of 250 participants will allow detection of a difference in a continuous outcome with 80% power and 1% two-sided alpha if the true difference in 0.3 standard deviations or more. Our analyses will adjust for baseline agreement with misinformation, and the degree of correlation between baseline and post-intervention will increase the power of the study and/or decrease the difference that can be detected. To adjust for dropouts and exclusions, we will increase the sample size by an additional 10%, totalling 1,100 participants.

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
ACT,NSW,NT,QLD,SA,TAS,WA,VIC

Funding & Sponsors
Funding source category [1] 314655 0
Other Collaborative groups
Name [1] 314655 0
Australian Partnership for Preparedness Research on Infectious Disease Emergencies (APPRISE)
Country [1] 314655 0
Australia
Primary sponsor type
Other Collaborative groups
Name
Kids Research
Address
178 Hawkesbury Rd, Westmead NSW 2145
Country
Australia
Secondary sponsor category [1] 316617 0
None
Name [1] 316617 0
None
Address [1] 316617 0
None
Country [1] 316617 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 313673 0
Sydney Children's Hospitals Network Human Research Ethics Committee
Ethics committee address [1] 313673 0
Ethics committee country [1] 313673 0
Australia
Date submitted for ethics approval [1] 313673 0
23/05/2023
Approval date [1] 313673 0
06/07/2023
Ethics approval number [1] 313673 0
2023/ETH01111

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

Contacts
Principal investigator
Name 128966 0
Dr Maryke Steffens
Address 128966 0
National Centre for Immunisation Research and Surveillance (NCIRS), Kids Research, Corner Hawkesbury Road and, Hainsworth St, Westmead NSW 2145 Australia
Country 128966 0
Australia
Phone 128966 0
+612 98451433
Fax 128966 0
Email 128966 0
Contact person for public queries
Name 128967 0
Maryke Steffens
Address 128967 0
National Centre for Immunisation Research and Surveillance (NCIRS), Kids Research, Corner Hawkesbury Road and, Hainsworth St, Westmead NSW 2145 Australia
Country 128967 0
Australia
Phone 128967 0
+612 98451433
Fax 128967 0
Email 128967 0
Contact person for scientific queries
Name 128968 0
Maryke Steffens
Address 128968 0
National Centre for Immunisation Research and Surveillance (NCIRS), Kids Research, Corner Hawkesbury Road and, Hainsworth St, Westmead NSW 2145 Australia
Country 128968 0
Australia
Phone 128968 0
+612 98451433
Fax 128968 0
Email 128968 0

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
Yes
What data in particular will be shared?
Individual de-identified participant data collected during the trial
When will data be available (start and end dates)?
Immediately following publication, no end date
Available to whom?
To researchers who provide a methodologically sound proposal
Available for what types of analyses?
Meta-analyses
How or where can data be obtained?
Access subject to approval by the Principal Investigator ([email protected])


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.