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Views on COVID-19 and Vaccination

If We Build It, Will They Come? A Pilot Study to Develop and Test Messages to Maximize Uptake of Coronavirus Vaccine When Available

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT04706403
Enrollment
756
Registered
2021-01-12
Start date
2021-01-12
Completion date
2021-02-01
Last updated
2022-05-24

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Covid19

Keywords

Covid-19, Vaccination

Brief summary

The goal of this study is to develop evidence-based messages that effectively mitigate concerns of people at risk for not being vaccinated against COVID-19, with the ultimate goal of maximizing vaccine uptake in vulnerable populations. The investigators will collect data on COVID-19 disease and vaccine knowledge, beliefs, and intent to be vaccinated from an existing online panel. Results from this data collection will be used to develop effective messages and communication strategies. The investigators will test alternate versions of messages intended to reduce vaccine hesitancy and promote vaccine uptake among vaccine-hesitant individuals. This project will ultimately result in a set of tested, evidence-derived messages about vaccination for COVID-19.

Detailed description

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has rapidly instigated a global pandemic. As of this writing, there are approximately 65 million documented cases of infection worldwide, and over 1.5 million deaths. In the United States (US), coronavirus disease 2019 (COVID-19) has disrupted the economy, overwhelmed healthcare system, led to widespread school cancellations, and caused more than 274,000 deaths since March 2020. A vaccine against COVID-19 is widely viewed as the key to controlling the pandemic and enabling a return to normal life. Vaccine development is proceeding at an unprecedented pace with 10 vaccines currently in phase 3 trials. Experts have projected that a safe and effective vaccine may be available by mid-2021. At the same time, a growing body of evidence indicates that a significant proportion of adults in the U.S. may not accept vaccination against COVID-19. Even more alarming, COVID-19 vaccine hesitancy (refusal or reluctance to accept a vaccine) appears to be increasing as the vaccine approval process becomes increasingly politicized. Just as efforts to develop vaccine production and delivery capacity have been undertaken in advance of having a proven effective vaccine, parallel efforts are needed to identify effective messages and communication strategies to overcome COVID-19 vaccine hesitancy. The study team recently surveyed a nationally representative sample of approximately 1,000 adults in the United States and found that only 57% intended to be vaccinated when a coronavirus vaccine becomes available. This percentage was even lower among people who identified as Black or Hispanic (39% and 43% respectively), those with a high school education or less (46%), and those in the lowest income groups (49% of those reporting a household income of $30,000 or less, compared to 72% of those reporting a household income of $100,000 or more). The investigators asked those who indicated they would not or might not get vaccinated for their reasons and found that some individuals may be willing to be vaccinated if provided specific information about the vaccine such as side effects and effectiveness. Others expressed generalized skepticism, fear, and distrust of vaccines, with some even referring to anti-vaccine conspiracy theories. These findings are consistent with an extensive body of research documenting that people often do not behave rationally and highlight the urgent need to proactively develop and test interventions to maximize vaccination rates when a coronavirus vaccine becomes available. To address this need, in the present study, the investigators aim to create and test targeted messages to address the concerns of subgroups of people at risk for not being vaccinated, with the ultimate goal of maximizing vaccine uptake when a vaccine for COVID-19 becomes available. The investigators will accomplish this by working with an existing online panel of volunteers, which will allow efficient, focused data gathering. Results of the survey will provide a nuanced, current description of how vulnerable adults perceive the coronavirus and available vaccines, which will be used as the basis for developing messages and communication strategies. Participants will be randomized to receive one of five different versions of a message from a healthcare provider regarding vaccination. Specific wording and content of these messages will vary systematically in order to address concerns of those at risk for not being vaccinated. This project will ultimately result in a set of tested, evidence-derived messages about vaccination for COVID-19. The investigators will make these messages available, together with evidence of how these influence members of vulnerable populations' understanding of vaccination, and disease risk, as well as intent to be vaccinated. The messages will be freely available for use by organizations and providers seeking to improve communication about a coronavirus vaccine.

Interventions

BEHAVIORALCommunication from a physician about the COVID-19 Vaccine

Participants who expressed hesitation about getting vaccinated against COVID-19 were randomized to receive one of five different versions of messages from a physician. The messages that participants in each group received varied slightly and systematically. Specific content and wording of these messages were developed to address and mitigate concerns of those at risk for not being vaccinated.

Sponsors

National Library of Medicine (NLM)
CollaboratorNIH
University of Massachusetts, Worcester
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* Adult (age 18 and over) who are members of an online panel (Prolific). Members of this panel joined the panel specifically to receive invitations to participate in research surveys and similar activities. * Able to complete an online survey in English.

Exclusion criteria

• None

Design outcomes

Primary

MeasureTime frameDescription
Number of Participants Who Became Less Hesitant About the COVID-19 Vaccine After Receiving a Physician MessageThrough survey completion, an average of 12 minutesAll participants were asked about their intent to be vaccinated against COVID-19 prior to exposure to one of the five physician messages (Response options: Yes, No, Not sure). After participants were randomly assigned to receive one of the five physician messages, reduction in COVID-19 vaccine hesitancy was assessed with the question: Would you get vaccinated at this visit. Response options included yes, no, not sure. For participants whose initial vaccination intent was not sure, a response of yes on re-assessment was defined as less hesitant. Response of not sure or yes were defined as less hesitant for participants whose initial vaccination intent was no.

Countries

United States

Participant flow

Recruitment details

Participants were recruited on Prolific.co from 01/12/21-02/01/21. Eligible panel members were \>= 18, English speaking, and U.S residents. Panel members were restricted to include White, Black, or Hispanic; Blacks and Hispanics were oversampled. Participants who responded no or not sure to If you could get vaccinated for COVID-19 today, would you? were classified as vaccine hesitant and randomized to receive 1 of 5 physician messages, after which their intent was reassessed.

Participants by arm

ArmCount
Message 1
Participants were randomized to receive version #1 of 5 different versions of a message from a physician regarding the COVID-19 vaccination. All messages included a statement that the vaccine is very safe and very effective. In Message 1, this statement was followed by a participatory-style recommendation (What do you think?)
172
Message 2
Participants were randomized to receive version #2 of 5 different versions of a message from a physician regarding vaccination. All messages included a statement that the vaccine is very safe and very effective. In Message 2, this statement was followed by a comparison of the COVID-19 vaccine to the flu shot and an explicit recommendation (I recommend that you get it).
121
Message 3
Participants were randomized to receive version #3 of 5 different versions of a message from a physician regarding vaccination. All messages included a statement that the vaccine is very safe and very effective. In Message 3, this statement was followed by a statement that millions of people have already received the COVID-19 vaccine and an explicit recommendation (I recommend that you get it).
164
Message 4
Participants were randomized to receive version #4 of 5 different versions of a message from a physician regarding vaccination. All messages included a statement that the vaccine is very safe and very effective. In Message 4, this statement was followed by an acknowledgement of concerns and reassurance that the physician personally reviewed the safety data and an explicit recommendation (I recommend that you get it).
145
Message 5
Participants were randomized to receive version #5 of 5 different versions of a message from a physician regarding vaccination. All messages included a statement that the vaccine is very safe and very effective. In Message 5, this statement was followed by an emphasis on protecting others an explicit recommendation (I recommend that you get it).
150
Total752

Withdrawals & dropouts

PeriodReasonFG000FG001FG002FG003FG004
Overall StudyParticipants did not provide respond to the question re-assessing vaccination intent00112

Baseline characteristics

CharacteristicTotalMessage 1Message 2Message 3Message 4Message 5
Age, Customized
Age
25 - 34 years
184 Participants40 Participants32 Participants42 Participants28 Participants42 Participants
Age, Customized
Age
35 - 44 years
191 Participants50 Participants27 Participants31 Participants50 Participants33 Participants
Age, Customized
Age
45 - 54 years
107 Participants22 Participants21 Participants27 Participants17 Participants20 Participants
Age, Customized
Age
55 - 64 years
58 Participants13 Participants4 Participants20 Participants10 Participants11 Participants
Age, Customized
Age
65 years or older
15 Participants3 Participants5 Participants3 Participants2 Participants2 Participants
Age, Customized
Age
Less than 24 years
190 Participants43 Participants31 Participants37 Participants38 Participants41 Participants
Age, Customized
Age
Missing
7 Participants1 Participants1 Participants4 Participants0 Participants1 Participants
Education
4-year college or more
160 Participants42 Participants25 Participants25 Participants36 Participants32 Participants
Education
High School or Less
224 Participants44 Participants40 Participants53 Participants38 Participants49 Participants
Education
Missing
3 Participants0 Participants0 Participants1 Participants1 Participants1 Participants
Education
Some college
365 Participants86 Participants56 Participants85 Participants70 Participants68 Participants
Employment
Disabled
28 Participants6 Participants3 Participants10 Participants4 Participants5 Participants
Employment
Employed
394 Participants88 Participants64 Participants83 Participants83 Participants76 Participants
Employment
Homemaker
64 Participants16 Participants12 Participants9 Participants14 Participants13 Participants
Employment
Missing
2 Participants0 Participants1 Participants1 Participants0 Participants0 Participants
Employment
Other
22 Participants4 Participants3 Participants10 Participants1 Participants4 Participants
Employment
Retired
21 Participants3 Participants3 Participants7 Participants4 Participants4 Participants
Employment
Student
92 Participants25 Participants15 Participants15 Participants19 Participants18 Participants
Employment
Unemployed
129 Participants30 Participants20 Participants29 Participants20 Participants30 Participants
Geographic region
Midwest
131 Participants28 Participants17 Participants34 Participants31 Participants21 Participants
Geographic region
Northeast
110 Participants26 Participants17 Participants27 Participants24 Participants16 Participants
Geographic region
South
391 Participants90 Participants66 Participants80 Participants75 Participants80 Participants
Geographic region
West
120 Participants28 Participants21 Participants23 Participants15 Participants33 Participants
History of flu shot
Ever, in the last 5 years
332 Participants73 Participants40 Participants70 Participants78 Participants71 Participants
History of flu shot
Missing
1 Participants0 Participants0 Participants1 Participants0 Participants0 Participants
History of flu shot
Not sure or no
419 Participants99 Participants81 Participants93 Participants67 Participants79 Participants
Household Income
$30,000 - $60,000
255 Participants53 Participants41 Participants57 Participants51 Participants53 Participants
Household Income
$60,000 - $100,000
159 Participants44 Participants27 Participants35 Participants26 Participants27 Participants
Household Income
Less than $30,000
242 Participants47 Participants43 Participants55 Participants40 Participants57 Participants
Household Income
Missing
4 Participants1 Participants1 Participants1 Participants0 Participants1 Participants
Household Income
More than $100,000
67 Participants21 Participants7 Participants11 Participants19 Participants9 Participants
Household Income
Prefer not to answer
25 Participants6 Participants2 Participants5 Participants9 Participants3 Participants
Initial Vaccination Intent
Initially No
411 Participants103 Participants66 Participants83 Participants78 Participants81 Participants
Initial Vaccination Intent
Initially Not Sure
341 Participants69 Participants55 Participants81 Participants67 Participants69 Participants
Race/Ethnicity, Customized
Black/African American
326 Participants79 Participants52 Participants66 Participants64 Participants65 Participants
Race/Ethnicity, Customized
Hispanic/Latino
177 Participants35 Participants31 Participants41 Participants33 Participants37 Participants
Race/Ethnicity, Customized
Missing
1 Participants0 Participants1 Participants0 Participants0 Participants0 Participants
Race/Ethnicity, Customized
White
248 Participants58 Participants37 Participants57 Participants48 Participants48 Participants
Region of Enrollment
United States
752 participants172 participants121 participants164 participants145 participants150 participants
Self-rated overall health
Excellent
69 Participants22 Participants12 Participants13 Participants9 Participants13 Participants
Self-rated overall health
Fair
137 Participants27 Participants19 Participants34 Participants33 Participants24 Participants
Self-rated overall health
Good
309 Participants69 Participants51 Participants66 Participants58 Participants65 Participants
Self-rated overall health
Missing
2 Participants1 Participants0 Participants0 Participants0 Participants1 Participants
Self-rated overall health
Poor
30 Participants9 Participants5 Participants3 Participants5 Participants8 Participants
Self-rated overall health
Very good
205 Participants44 Participants34 Participants48 Participants40 Participants39 Participants
Self-rated overall mental health
Excellent
91 Participants22 Participants17 Participants22 Participants12 Participants18 Participants
Self-rated overall mental health
Fair
185 Participants51 Participants20 Participants39 Participants35 Participants40 Participants
Self-rated overall mental health
Good
225 Participants42 Participants38 Participants48 Participants47 Participants50 Participants
Self-rated overall mental health
Missing
1 Participants0 Participants0 Participants0 Participants1 Participants0 Participants
Self-rated overall mental health
Poor
76 Participants14 Participants15 Participants18 Participants17 Participants12 Participants
Self-rated overall mental health
Very good
174 Participants43 Participants31 Participants37 Participants33 Participants30 Participants
Sex/Gender, Customized
Gender
Female
449 Participants108 Participants78 Participants88 Participants93 Participants82 Participants
Sex/Gender, Customized
Gender
Male
291 Participants62 Participants41 Participants71 Participants52 Participants65 Participants
Sex/Gender, Customized
Gender
Missing
5 Participants1 Participants0 Participants1 Participants0 Participants3 Participants
Sex/Gender, Customized
Gender
Other
6 Participants0 Participants2 Participants4 Participants0 Participants0 Participants
Sex/Gender, Customized
Gender
Prefer not to say
1 Participants1 Participants0 Participants0 Participants0 Participants0 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
EG002
affected / at risk
EG003
affected / at risk
EG004
affected / at risk
deaths
Total, all-cause mortality
0 / 00 / 00 / 00 / 00 / 0
other
Total, other adverse events
0 / 00 / 00 / 00 / 00 / 0
serious
Total, serious adverse events
0 / 00 / 00 / 00 / 00 / 0

Outcome results

Primary

Number of Participants Who Became Less Hesitant About the COVID-19 Vaccine After Receiving a Physician Message

All participants were asked about their intent to be vaccinated against COVID-19 prior to exposure to one of the five physician messages (Response options: Yes, No, Not sure). After participants were randomly assigned to receive one of the five physician messages, reduction in COVID-19 vaccine hesitancy was assessed with the question: Would you get vaccinated at this visit. Response options included yes, no, not sure. For participants whose initial vaccination intent was not sure, a response of yes on re-assessment was defined as less hesitant. Response of not sure or yes were defined as less hesitant for participants whose initial vaccination intent was no.

Time frame: Through survey completion, an average of 12 minutes

Population: Four participants were excluded from the analyses because they did not respond to the question re-assessing vaccination intent following exposure to a physician recommendation.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Message 1Number of Participants Who Became Less Hesitant About the COVID-19 Vaccine After Receiving a Physician Message23 Participants
Message 2Number of Participants Who Became Less Hesitant About the COVID-19 Vaccine After Receiving a Physician Message26 Participants
Message 3Number of Participants Who Became Less Hesitant About the COVID-19 Vaccine After Receiving a Physician Message43 Participants
Message 4Number of Participants Who Became Less Hesitant About the COVID-19 Vaccine After Receiving a Physician Message35 Participants
Message 5Number of Participants Who Became Less Hesitant About the COVID-19 Vaccine After Receiving a Physician Message40 Participants

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026