Addressing Myths and Vaccine Hesitancy: A Randomized Trial

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Addressing Myths and Vaccine Hesitancy: A Randomized Trial
Addressing Myths and Vaccine
                                     Hesitancy: A Randomized Trial
                                      Maryke S. Steffens, PhD,a Adam G. Dunn, PhD,b Mathew D. Marques, PhD,c Margie Danchin, PhD,d,e
                                      Holly O. Witteman, PhD,f Julie Leask, PhDg

OBJECTIVES:Evidence on repeating vaccination misinformation or "myths" in debunking text is                                                      abstract
inconclusive; repeating myths may unintentionally increase agreement with myths or help
discredit myths. In this study we aimed to compare the effect of repeating vaccination myths
and other text-based debunking strategies on parents’ agreement with myths and their
intention to vaccinate their children.
METHODS: For this online experiment we recruited 788 parents of children aged 0 to 5 years;
454 (58%) completed the study. We compared 3 text-based debunking strategies (repeating
myths, posing questions, or making factual statements) and a control. We measured changes
in agreement with myths and intention to vaccinate immediately after the intervention and at
least 1 week later. The primary analysis compared the change in agreement with vaccination
myths from baseline, between groups, at each time point after the intervention.
RESULTS:There was no evidence that repeating myths increased agreement with myths
compared with the other debunking strategies or the control. Posing questions significantly
decreased agreement with myths immediately after the intervention compared with the
control (difference: 0.30 points, 99.17% confidence interval: 0.58 to 0.02, P 5 .004,
d 5 0.39). There was no evidence of a difference between other debunking strategies or the
control at either time point, or on intention to vaccinate.
CONCLUSIONS:Debunking strategies that repeat vaccination myths do not appear to be inferior to
strategies that do not repeat myths.

Full article can be found online at www.pediatrics.org/cgi/doi/10.1542/peds.2020-049304
a
  Centre for Health Informatics, Australian Institute of Health Innovation, Macquarie University, Sydney,
Australia; bBiomedical Informatics and Digital Health, School of Medical Sciences, Faculty of Medicine and Health,   WHAT’S KNOWN ON THIS SUBJECT: Vaccination
The University of Sydney, Sydney, Australia; cSchool of Psychology and Public Health, Department of Psychology and   misinformation may fuel hesitancy and refusal and factor
Counselling, La Trobe University, Melbourne, Australia; dVaccine Uptake Research Group, Murdoch Children’s
                                                                                                                     in vaccine-preventable disease outbreaks. Evidence on
Research Institute, Melbourne, Australia; eDepartment of Paediatrics, The University of Melbourne, Melbourne,
Australia; fDepartment of Family and Emergency Medicine, Faculty of Medicine, Laval University, Quebec, Canada;
                                                                                                                     repeating vaccination misinformation or “myths” in
and gSusan Wakil School of Nursing and Midwifery, Faculty of Medicine and Health, The University of Sydney,          debunking text is inconclusive; repeating myths may
Sydney, Australia                                                                                                    unintentionally increase agreement with myths or help
                                                                                                                     discredit myths.
Dr Steffens performed the literature search, developed the study design and protocol,
conducted the statistical analysis and interpretation of the data, developed the figures and                           WHAT THIS STUDY ADDS: This online experiment was
tables, drafted the initial manuscript, and reviewed and revised the manuscript; Drs Dunn,                           conducted in parents of children
Addressing Myths and Vaccine Hesitancy: A Randomized Trial
Childhood vaccination raises               examples of misinformation or                    Participants were parents of
questions and concerns for 40% of         “myths” before debunking them.                   children aged 0 to 5 years. Eligible
parents in Australia.1 In addition to      With this strategy, myths are often              participants were 18 years or older,
practical barriers to vaccination,         presented as headings, followed by               residing in Australia, and competent
vaccine concerns among parents can         corrective, evidence-based text.14,15            at reading and responding in
lower childhood vaccination rates          Reviews of evidence and some                     English. Participants gave written
and are associated with outbreaks of       recent studies, however, suggest this            informed consent. The Macquarie
measles and pertussis.2,3 Vaccine          approach may be flawed: repeating                University Human Research Ethics
misinformation (information not            a myth may backfire by rendering it              Committee granted ethics approval
supported by evidence) can                 memorable and thus likely to be                  (ref. 5201954658790).
exacerbate parental concerns:              recalled as true on the basis of
shared in social networks or spread        recall and familiarity, a phenomenon             Procedure
by those seeking to oppose                 known as familiarity bias.16–19                  Research company Quality Online
vaccination,4,5 misinformation may         Hence, recommendations for                       Research recruited participants from
reduce confidence in vaccination by        debunking misinformation have                    its accredited online panel, the
increasing perceptions of risk.6,7         emphasized providing factual                     representativeness of which is
Misinformation provides an                 information over repeating myths to              obtained by using quota controls
underpinning for misperceptions            avoid triggering familiarity backfire            according to Australian Bureau of
such as vaccines overwhelming              effects.20 Authors of a recent review,           Statistics Census data. The company
children’s immune systems and the          however, have questioned whether                 recruited participants between
dangers of giving too many vaccines        backfire effects reliably occur,21               September 16 and October 30, 2019,
too early, the preference for natural      while other research has failed to               inviting them via e-mail or survey
rather than vaccine-induced                reveal evidence that repeating                   technology and offering between
immunity, and the association of           myths is counterproductive.22–25                 A$1.00 and A$3.00 as incentive for
vaccines with autism.1,8                   The literature on debunking                      participation. The company stopped
                                           vaccination misinformation is                    recruitment when predetermined
Countering misinformation is key to
                                           limited. This gap in evidence is                 targets were achieved.
avoiding negative effects on
                                           important to address, especially in
vaccination attitudes.9 Parents of
                                           view of the deployment of                        At baseline, participants responded
young children are at high risk of
                                           coronavirus disease of 2019 (COVID-              to myth agreement, intention to
misinformation exposure10 and are
                                           19) vaccines, which are subject to a             vaccinate, and vaccine confidence
important targets for interventions
                                           range of claims made by opponents                items (see Materials for definitions).
to counter misinformation.
                                           of vaccination.                                  Participants were randomly
Encouragingly, parents indicate
                                                                                            assigned to receive 1 of 3 debunking
receptiveness to trusted sources
                                           With this study, we sought to assist             interventions or a control text.
that address their concerns and
                                           health communicators addressing                  Immediately after the intervention,
provide accurate, evidenced-based
                                           misinformation about childhood                   participants responded to myth
information.11 Global health
                                           vaccination with evidence on the                 agreement and intention to
agencies, like the World Health
                                           effectiveness of various debunking               vaccinate items again. Participants
Organization and United Nations
                                           strategies. The aim of this study was            were also asked to provide
Children’s Fund (UNICEF), health
                                           to compare how different text-based              demographic information. For
care providers, other advocates of
vaccination, and the media all play a      debunking strategies affect parents’             quality control, participants were
key role in addressing                     agreement with vaccination myths                 asked to summarize the intervention
misinformation, especially in online       and their intention to vaccinate their           text in a free-response text box.
settings, where it is most easily          children.                                        After 1 week, participants were
spread.12                                                                                   invited to complete a follow-up
                                           METHODS                                          survey responding to myth
Commonly used strategies to                                                                 agreement and intention to
address misinformation, however,
                                           Participants                                     vaccinate items. They had up to 3
have been shown to have adverse            This was a prospective online                    weeks to respond. At the close of
rather than positive effects in parent     experiment testing a communication               study, participants were given a
populations.13 One frequently used         intervention aimed at reducing                   debriefing statement with credible
strategy to counter misinformation         agreement with vaccination myths                 information correcting vaccination
is to prominently repeat specific          in parents of young children.                    myths used in the intervention.

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2                                                                                                                     STEFFENS et al
Addressing Myths and Vaccine Hesitancy: A Randomized Trial
The study aimed to recruit 452                      were included in the analysis (Fig 1).      vaccinate at baseline. Participants
participants to ensure a sample size                Of the 454 participants included, 63%       who did not complete the follow-up
of 376 participants (with an                        were female (284 of 454), 56% (255          survey were more likely to be
expected 17% loss to follow-up),                    of 454) were aged between 30 and            female (x2 5 9.91, P 5 .007) and
calculated to allow detection of an                 39 years, 60% (272 of 454) had a            have a lower vaccine confidence
effect size of d 5 0.5 when                         household income of $80 0001 per            score at baseline (P 5 .046, Cohen’s
comparing change in myth                            year, and 61% (275 of 454) had              d 5 0.15). There was no evidence of
agreement (primary outcome)                         university qualifications.                  a difference in myth agreement or
between groups (see Supplemental                                                                intention to vaccinate at baseline
Information for sample size                         Mean response time between baseline         between participants who did and
calculations). This study was                       and follow-up survey was 16 (SD 5           did not complete the follow-up
powered at 80% to be confirmatory                   5.55) days. Of the 788 randomly             survey. There was no significant
for the primary outcome.                            assigned participants, 14% (107 of          difference in attrition across
Participants with incomplete                        788) were excluded because of their         intervention groups (x2[N 5 681,
surveys or poor-quality free                        poor-quality responses, while 29%           df 53] 5 2.85, P 5 .42).
responses (off-topic, unclear,                      (227 of 788) failed to respond to the
unanswered) or who responded too                    invitation to complete a follow-up          Materials
quickly (determined a priori by the                 survey; this attrition was higher than
                                                                                                Intervention
research company as per their                       the expected 17%. There was no
quality control measures) were                      significant difference in exclusion         Participants were asked to read a
excluded by the research company.                   across intervention groups (x2[N 5          short piece of text (350 words)
                                                    788, df 53] 5 1.70, P 5 .64).               debunking 3 vaccination myths. The
Of the 788 parents of children aged 0                                                           3 myths were “It’s better for
to 5 years who consented and were                   Attrition analysis compared sex and         children to develop immunity from
randomly assigned, 454 (58%)                        measures of vaccine confidence,             diseases”; “It’s safer to vaccinate
completed the follow-up survey and                  myth agreement, and intention to            babies and young children when

FIGURE 1
Flow diagram revealing progress of participants through the online experiment.

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they are older”; and “Vaccines                         text with a similar length and                1 5 strongly disagree, 5 5 strongly
overwhelm a baby's immune                              structure about parenting strategies.         agree; a 5 .85) and were averaged
system.” The text was modified from                    Survey software required                      to create a vaccine confidence score.
a resource addressing common                           participants to view this page for a
vaccine misperceptions developed to                    minimum of 30 seconds (see                    Data Analysis
support health care providers’                         Supplemental Information for full
                                                                                                     The primary outcome measure was
consultations with parents.26                          intervention texts).
                                                                                                     the change in myth agreement,
Each intervention (myth, question,                     Survey Items                                  calculated as the difference from
or statement) used a different                                                                       baseline at each time point after the
                                                       Myth agreement was assessed with
debunking strategy to counter the                                                                    intervention. The primary analysis
                                                       3 items, by using a 5-point scale
                                                                                                     compared mean change in myth
myths. The myth intervention                           (1 5 strongly disagree, 5 5 strongly
repeated the vaccination myths                                                                       agreement between groups, at each
                                                       agree). The responses to each of the
(“Myth: Vaccines overwhelm a                                                                         time point after the intervention.
                                                       3 individual vaccination myths
baby’s immune system”) in the                                                                        For this analysis, independent
                                                       described above were averaged to
headings before providing corrective                                                                 samples t tests were used, adjusted
                                                       create a myth agreement score,
text. The question intervention                        which revealed high internal                  for multiple comparisons between
posed questions (“Can vaccines                         consistency at baseline (a 5 .84),            groups with Bonferroni correction
overwhelm a baby’s immune                              immediately after the intervention            (P < .0083; confidence intervals
system?”) in the headings before                       (a 5 .85), and 11 weeks after the             [CIs] of 99.17%). Cohen’s d was
providing corrective text. The                         intervention (a 5 .84). Intention to          calculated to describe the magnitude
statement intervention made factual                    vaccinate was assessed with a single          of intervention effects.30
statements (“A baby’s immune                           item, by using a 0 to 100 scale               Observational within-group changes
system to able to respond to a                         (0 5 definitely not, 100 5 defini-            in myth agreement from baseline
vaccine and fight germs at the same                    tely). Myth agreement and intention           were also analyzed by using
time”) in the headings before                          to vaccinate items were consistent            repeated measures analysis of
providing corrective text. The                         with survey questions used in stu-            variance (ANOVA). The findings of
corrective text was the same for                       dies with similar parent popula-              the difference-in-difference analyses
each intervention (Fig 2); only the                    tions.8,27 Vaccine confidence was             were confirmed with a repeated
headings differed between                              measured by using the 4-item short            measures analysis of covariance
interventions. Participants in the                     form of the Vaccine Confidence Scale          (ANCOVA ) (see Supplemental
control group were given unrelated                     (benefits factor)28,29 (5-point scale,        Information).

FIGURE 2
Intervention texts, comprising 3 vaccination myths, followed by corrective text.

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4                                                                                                                             STEFFENS et al
A secondary outcome measure was                                    Preregistration                                             99.17% CI: 0.58 to 0.02, P 5 .004,
the change in intention to vaccinate,                              The study aims and hypotheses,                              Cohen’s d 5 0.39). We found no clear
calculated as the difference from                                  methods, and data analysis plan                             evidence of a difference between
baseline at each time point after the                              were preregistered with the Open                            change in myth agreement between
intervention. Changes between                                      Science Framework (https://osf.io/                          the control and other groups or
groups were compared by using                                      jthn2). A minor variation to the pre-                       between the groups themselves: there
independent samples t tests.                                       registration was to analyze myth                            was no evidence of differences
Observational within-group changes                                 agreement as a composite score,                             between any other groups at this time
from baseline were analyzed by                                                                                                 point or at 11 weeks after the
                                                                   with the aim of presenting simple
using repeated measures ANOVAs.                                                                                                intervention. This includes the myth
                                                                   and straightforward results in the
All analyses were conducted by                                                                                                 group, which did not increase myth
                                                                   article. An analysis of change in
using SPSS (version 25; IBM SPSS                                                                                               agreement compared with the other
                                                                   myth agreement for each individual
Statistics, IBM Corporation).                                                                                                  groups or the control at any time
                                                                   myth is retained in the Supplemen-
                                                                                                                               point (see Table 3). There was no
Subgroup Analysis                                                  tal Information.
                                                                                                                               evidence of a difference between
A prespecified subgroup analysis                                                                                               groups in intention to vaccinate at any
included data from 217 moderate-                                   RESULTS
                                                                                                                               time point. The results of the repeated
low vaccine confidence participants                                At baseline, mean myth agreement                            measures ANCOVA aligned with those
only (48%; 217 of 454). Participants                               scores were between neutral (3) and                         of the difference-in-difference analyses
were categorized as moderate-low                                   slightly disagree (2) (see Table 1).                        (see Supplemental Information).
vaccine confidence if their vaccine                                Within-group observational changes
confidence score measured at                                       in myth agreement, both imme-                               Comparing changes in myth
baseline (5 point scale, 1 5 strongly                              diately after the intervention and                          agreement between groups for each
disagree, 5 5 strongly agree) was                                  11 weeks after the intervention, are                        myth individually indicated differences
#4.38. High vaccine confidence                                     shown in Table 2 and Fig 3.                                 between myths. For the “Vaccines
participants (score >4.38) (52%;                                                                                               overwhelm immune systems” myth,
237 of 454) were excluded. These                                   The primary analysis compared the                           the question and myth groups showed
categories are based on results of a                               change in myth agreement from                               a significant decrease in myth
previous study in parents of young                                 baseline, between groups, at each time                      agreement of a medium size
children, in which a score of #4.38                                point after the intervention. The                           compared with the control (difference
(converted from a score by using an                                results of this analysis are shown in                       between question and control: 0.45
11 point scale) was associated with                                Table 3. The null hypothesis for                            points, 99.17% CI: 0.81 to 0.09,
delay of any vaccine.29 Mean                                       comparing change in myth agreement                          P 5 .001, Cohen’s d 5 0.45; difference
changes in myth agreement and                                      between posing questions and control                        between myth and control: 0.31
intention to vaccinate were                                        immediately after the intervention                          points, 99.17% CI: 0.59 to 0.03, P
compared between groups, at each                                   was rejected: compared with the                             5 .004, Cohen’s d 5 0.38). There
time point after the intervention.                                 control group, the question group                           were no significant differences
Independent samples t tests were                                   showed a significant decrease in                            between groups for the “Disease-
used for this analysis, adjusting for                              agreement with vaccination myths of                         acquired immunity is better” myth or
multiple comparisons between                                       a medium effect size immediately                            the “Delaying vaccines is safer” myth
groups with Bonferroni correction                                  after the intervention (difference                          (see Supplemental Table 6 for full
(P < .0083).                                                       between groups: 0.30 points,                                results of analysis per myth).

TABLE 1 Vaccination-Specific Characteristics of Participants by Intervention Group at Baseline, Immediately After the Intervention and 11 Week After
             the Intervention
                                       Myth Agreement,a Mean Score (SD)                      Intention to Vaccinate,b Mean Score (SD)
                                                                                                                                                     Vaccine Confidence,c Mean
                                 Baseline      Immediately After       11 wk After        Baseline        Immediately After        11 wk After          Score (SD), Baseline
    All (n 5 454)              2.39   (1.06)       2.20   (1.04)        2.19   (1.02)   92.00   (15.26)      92.29   (15.94)       91.90   (16.06)          4.33   (0.65)
    Myth (n 5 127)             2.41   (1.00)       2.20   (1.03)        2.14   (1.00)   92.61   (12.58)      92.81   (14.82)       91.76   (15.80)          4.32   (0.63)
    Question (n 5 118)         2.37   (1.18)       2.03   (1.08)        2.12   (0.96)   93.23   (14.28)      93.57   (13.17)       91.88   (16.76)          4.37   (0.69)
    Statement (n 5 103)        2.36   (1.07)       2.20   (1.03)        2.17   (1.00)   88.91   (19.67)      90.74   (17.66)       90.99   (16.50)          4.34   (0.70)
    Control (n 5 106)          2.42   (0.97)       2.38   (1.02)        2.36   (1.12)   92.89   (14.12)      91.75   (18.19)       92.99   (15.28)          4.30   (0.60)
a
    Five-point scale, 1 5 strongly disagree, 5 5 strongly agree; higher scores indicate more agreement with vaccination myths.
b
    Scale of 0–100, 0 5 definitely not, 100 5 definitely; higher scores indicate stronger intention to vaccinate.
c
    Five-point scale, 1 5 strongly disagree, 5 5 strongly agree; higher scores indicate more positive beliefs about vaccination.

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TABLE 2 Within-Group Observational Mean Change in Myth Agreement and Intention to Vaccinate From Baseline, Immediately After the Intervention
            and 11 Week After the Intervention
                                                                   Immediately After the Intervention                           11 wk After the Intervention

                                                           M Diff (SD)      df, Error    F        P       np2        M Diff (SD)      df, Error    F        P        np2
                               a
    Change in myth agreement from baseline
      Myth                                                 0.20   (0.87)     1,   126   17.18
TABLE 3 Comparing Mean Change in Myth Agreement and Intention to Vaccinate Between Groups
                                                                                Immediately After the Intervention                 11 wk After the Intervention

                                                                                                             99.17% CI                                       99.17% CI

                                                                         M Diff        t (df)         P     Lower Upper M Diff         t (df)         P     Lower Upper
 Comparing change in myth agreement from baseline
   Myth versus question                                                  0.15        1.579   (243)   .116   0.10     0.39   0.01     0.101   (243)   .920    0.30   0.28
   Myth versus statement                                                 0.05        0.593   (228)   .554   0.26     0.16   0.08     0.812   (228)   .418    0.33   0.18
   Myth versus control                                                   0.16        1.954   (231)   .052   0.37     0.06   0.21     2.058   (231)   .041    0.47   0.06
   Question versus statement                                             0.19        1.846   (219)   .066   0.47     0.09   0.07     0.565   (219)   .572    0.38   0.25
   Question versus control                                               0.30*       2.884   (222)   .004   0.58     0.02   0.19     1.606   (222)   .110    0.52   0.13
   Statement versus control                                              0.11        1.207   (207)   .229   0.36     0.13   0.13     1.181   (207)   .239    0.42   0.16
 Comparing change in intention to vaccinate from baseline
   Myth versus question                                                  0.14        0.127   (243)   .899   3.12     2.84   0.49     0.270   (243)   .787    4.33   5.31
   Myth versus statement                                                 1.63        1.139   (228)   .256   5.44     2.18   2.94     1.371   (228)   .172    8.64   2.76
   Myth versus control                                                   1.34        0.934   (231)   .351   2.48     5.15   0.96     0.629   (231)   .530    5.03   3.11
   Question versus statement                                             1.49        1.168   (219)   .244   4.88     1.90   3.43     1.522   (219)   .129    9.42   2.57
   Question versus control                                               1.48        1.154   (222)   .250   1.94     4.90   1.45     0.892   (222)   .373    5.78   2.88
   Statement versus control                                              2.97        1.836   (207)   .068   1.34     7.27   1.97     0.985   (207)   .326    3.37   7.31
df, degree of freedom; M Diff, mean difference.
*Mean difference significant at the 0.0083 level; 99.17% CI is Bonferroni adjusted.

reduce misinformation effects.31                              values related to bodily purity                            misconceptions.35 Experiments
Research comparing message                                    versus degradation.32 Equally, the                         with vaccination misinformation
formats for debunking influenza                               novelty of a myth to an individual                         specifically would be worthwhile
vaccination misinformation has also                           may render corrections                                     conducting, as would further
found that accurate knowledge                                 ineffective.33                                             investigations of the relationship
increases after debunking,                                                                                               between novel vaccine
regardless of the message format,                             This study has implications for how                        misinformation and social media
and that repeating misinformation                             health professionals, global health                        amplification.
does not inadvertently increase                               authorities, and other advocates of
inaccurate knowledge.22 Repeating                             vaccination debunk vaccine                                 This research was conducted in
misinformation with corrective text                           misinformation in written text. In                         parents of children
participants’ willingness to accept                     may improve intentions. Finally, in                      Further research should elucidate
the debunking information. Although                     this study, myth agreement was                           why some myths are more
the sample was intended to be                           analyzed as a continuous variable.                       persistent than others and evaluate
representative of the population,                       Informal analysis of the data as                         debunking strategies for novel
respondents analyzed were not,                          categories of agreeing and                               vaccination myths and those that
which may impact on the external                        disagreeing parents (not included                        change behavior.
validity of the findings. Parents’                      here) suggests exposing parents to
vaccination intention, rather than                      vaccination myths without                                ACKNOWLEDGMENTS
uptake, was measured as an                              corrective text may increase myth                        We acknowledge the contributions
outcome. Although in keeping with                       agreement. This effect is worth                          of Noel Brewer and Ullrich Ecker in
similar studies, uptake would                           investigating further in future                          critiquing and improving this article.
provide a more accurate measure of
                                                        research.
vaccination behavior. Furthermore,
no significant findings for parents’
                                                        CONCLUSIONS                                                 ABBREVIATIONS
vaccination intentions were
observed. Further investigation of                      In this study, repeating myths as a                         ANCOVA: analysis of covariance
how parents’ agreement with                             debunking strategy did not appear                           CI: confidence interval
vaccination myths is associated with                    to be inferior to strategies that do                        COVID-19: coronavirus disease of
intentions and behavior is                              not. Posing myths as questions may                                     2019
warranted, as is research into what                     be an effective debunking strategy
types of debunking interventions                        when paired with corrective text.

DOI: https://doi.org/10.1542/peds.2020-049304
Accepted for publication Aug 3, 2021
Address correspondence to Maryke S. Steffens, PhD, Australian Institute of Health Innovation, Macquarie University, North Ryde 2113 NSW Australia. E-mail:
maryke.steffens@health.nsw.gov.au
PEDIATRICS (ISSN Numbers: Print, 0031-4005; Online, 1098-4275).
Copyright © 2021 by the American Academy of Pediatrics
FINANCIAL DISCLOSURE: The authors have indicated they have no financial relationships relevant to this article to disclose.
FUNDING: Supported by Macquarie University Research Training Program Scholarship 2017438 and National Health and Medical Research Council project
grant APP1128968. The funder/sponsor did not participate in the work.
POTENTIAL CONFLICT OF INTEREST: During the conduct of the study, Dr Steffens reports funding from Macquarie University; Dr Dunn reports grants from the
National Health and Medical Research Council; Dr Leask reports grants from the National Health and Medical Research Council and funding from the World Health
Organization; Dr Witteman reports funding from the Canada Research Chairs program and grants from the Canadian Institutes of Health Research; and Drs Marques
and Dr Danchin have indicated they have no potential conflicts of interest to disclose.

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Addressing Myths and Vaccine Hesitancy: A Randomized Trial
Maryke S. Steffens, Adam G. Dunn, Mathew D. Marques, Margie Danchin, Holly O.
                            Witteman and Julie Leask
             Pediatrics originally published online October 11, 2021;

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Addressing Myths and Vaccine Hesitancy: A Randomized Trial
Maryke S. Steffens, Adam G. Dunn, Mathew D. Marques, Margie Danchin, Holly O.
                            Witteman and Julie Leask
             Pediatrics originally published online October 11, 2021;

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 http://pediatrics.aappublications.org/content/early/2021/10/08/peds.2020-049304

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