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PROmotion of COVID-19 BOOSTer VA(X)Ccination in the Emergency Department - PROBOOSTVAXED

PROmotion of COVID-19 BOOSTer VA(X)Ccination in the Emergency Department - PROBOOSTVAXED

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT06156215
Acronym
PROBOOSTVAXED
Enrollment
919
Registered
2023-12-05
Start date
2024-01-19
Completion date
2024-08-18
Last updated
2025-09-12

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

Conditions

COVID-19

Keywords

COVID-19, health disparities, booster vaccines, healthcare access, vaccination, public health

Brief summary

The goal of this cluster randomized clinical trial is to test the efficacy of messaging interventions to increase booster vaccine uptake in adults in the emergency department(ED). The main question\[s\] and goals of this study are: * does the intervention of vaccine messaging increase booster vaccine uptake at 30 days post ED visit? * does the intervention of asking about vaccine acceptance increase booster vaccine uptake at 30 days post ED visit? * considering recent national changes to funding and availability of updated vaccines, the investigators will examine the effects of these changes on vaccine acceptance and uptake in ED populations. Specifically, they will stratify EDs and ED patients according to the ED availability of vaccines, and they will also examine whether costs and availability of vaccines are a deterrent to patient acceptance and uptake of vaccines

Detailed description

I. Overview On January 22, 2020, Acting Health and Human Services Secretary Norris Cochran declared COVID-19 a national public health emergency, an action that eventually enabled emergency authorization for free COVID-19 vaccines, testing and treatments. This public health declaration has been renewed seven times for 90-day intervals, as required under section 319 of the Public Health Service (PHS) Act. Under this declaration over the past two years, the US government has provided full support and distribution of COVID-19 vaccines and therapeutics (antibody therapies, remdesivir, and nirmatrelvir/ritonavir), such that they have been widely available and free of charge to all Americans. Although these measures have not, by any means, ended the pandemic, it is clear from multiple epidemiologic modeling studies that they have decreased hospitalizations and saved hundreds of thousands of lives. They have also led to a narrowing of the profound morbidity and mortality disparities gap that was seen in minority populations in the first two waves of the pandemic. The PROCOVAXED trial was a multicenter study that sought to decrease COVID-19 vaccine hesitancy and increase COVID-19 vaccine uptake through the use of vaccine messaging platforms in the emergency department (ED). In this trial, investigators found that implementation of our COVID-19 messaging platforms (videos, information sheets and scripted, direct messaging) were associated with greater COVID-19 vaccine acceptance and uptake among unvaccinated ED patients (Rodriguez RM, Nichol G, Eucker SA, et al. Effect of COVID-19 Vaccine Messaging Platforms in Emergency Departments on Vaccine Acceptance and Uptake: A Cluster Randomized Clinical Trial. JAMA Intern Med. 2023;183(2):115-123. doi:10.1001/jamainternmed.2022.5909). In January 2022, the investigators extended PROCOVAXED by shifting the focus to vaccinated ED patients to examine the timely and critically important topic of booster vaccine hesitancy in underserved ED populations. To better characterize COVID-19 booster hesitancy, the investigators performed a cross-sectional study at five high-volume, safety-net hospital EDs in four cities (San Francisco, Philadelphia, Seattle, and Durham, NC) using survey tools to gather quantitative data on vaccination status, demographic variables, usual source of care, and attitudes toward booster vaccination. Of 771 participants who had completed their full initial series, 316 (41%) had not received any booster vaccine. Among these 316 non-boosted participants, 179 (57%, 95% CI 51-62) stated they would decline or were unsure whether they would accept a booster vaccine if it was offered to them (i.e., booster-hesitant). Investigators found the following associations with booster vaccine hesitancy: age 35-49 years vs age 18-34 years (OR 1.16, 95% CI 0.99-1.36); Asian vs White race (OR 0.21, 95% CI 0.05-0.93); Hispanic/Latino vs White ethnicity (OR 1.59, 95% CI 0.82-3.09); primary language non-English vs English (OR 2.35, 95% CI 1.49-3.71); and Republican vs Democrat party affiliation (OR 6.07, 95% CI 4.21-8.75). The three most common reasons for booster vaccine hesitancy were a preference to wait for more information (25%), concerns about side effects and safety (24%), and I don't need one because I'm fully vaccinated (20%). Recognizing the ED as a unique opportunity to address COVID-19 booster vaccine hesitancy in underserved populations, the investigators will launch the PROmotion of COVID-19 BOOSTer VA(X)ccination in the Emergency Department (PROBOOSTVAXED) trial as an extension of the PROCOVAXED trial, seeking to increase COVID-19 booster vaccine acceptance and uptake among vaccinated ED patients. Because of Omicron variant-associated surges during the COVID-19 pandemic with corresponding research staff illness and ED overcrowding, the investigators found wide week-to-week fluctuations in enrollment in the PROCOVAXED study. To reduce this variability of enrollment, the investigators have changed the unit of randomization from 1-week to 1-day in the PROBOOSTVAXED trial. As of May 11, 2023, the COVID-19 public health emergency ended. Consequently, not only are the costs for vaccines, testing, and treatments shifted to health insurers and patients via commercial payment mechanisms, but COVID-19 vaccines are no longer available in some EDs. Since our research focuses on the delivery and availability of vaccines to underserved populations whose only health care access occurs in EDs, the team believes that this represents a potential barrier to 30-day vaccine uptake in these populations. The investigators have been informed that only some of the PROBOOSTVAXED study sites will have COVID-19 vaccines available for distribution in the ED, and this availability is subject to change throughout the study period. Nevertheless, the team will proceed with the same research protocol, however, the investigators feel it is important to examine how ED vaccine availability will affect 30-day vaccine uptake in underserved populations. They will therefore be performing additional subgroup analyses that compare 30-day vaccine uptake among sites with available COVID-19 vaccine to those without for the intervention and control arms.They will also evaluate whether patient costs of vaccines are a deterrent to acceptance and uptake. While the sample size calculation for this research is derived from Aim 1, the investigators emphasize that this is a pragmatic study in which they seek to evaluate the fluid real-world changes in COVID-19 vaccine availability and funding. As stated above, there have been (and likely will continue to be) changes in payment for and availability of vaccines in EDs. The investigators therefore have developed our protocol and aims below to assess the impact of these changes. Aim1: To determine whether implementation of COVID-19 booster vaccine trusted messaging platforms is associated with increased booster vaccine uptake in ED patients. At five EDs (Zuckerberg San Francisco General, UCSF Parnassus Medical Center \[San Francisco, CA\], Thomas Jefferson University Hospital \[Philadelphia, PA\], Ben Taub Hospital \[Houston, TX\], Duke University Medical Center \[Durham, NC\]), investigators will conduct a cluster-randomized controlled trial of the implementation of PROBOOSTVAXED trusted messaging platforms, with 30-day booster vaccine uptake as the primary outcome and booster vaccine uptake in the ED as a secondary outcome. Hypothesis: Implementation of PROBOOSTVAXED trusted messaging platforms in EDs will be associated with increased 30-day booster vaccine uptake in vaccinated ED patients. Aim 1a: To determine whether implementation of COVID-19 booster vaccine trusted messaging platforms in EDs is associated with increased booster vaccine acceptance in ED patients. For this aim, booster vaccine acceptance in the ED assessed via ED survey will be the primary outcome. Hypothesis: Implementation of PROBOOSTVAXED trusted messaging platforms in EDs will be associated with increased booster vaccine acceptance in ED patients. Aim 2: To determine whether implementation of a protocol in which ED patients are asked whether they will accept a COVID-19 booster vaccine in the ED is associated with increased booster vaccine uptake in ED patients. Hypothesis: Implementation of an ED protocol in which patients are asked whether they will accept a COVID-19 booster vaccine will be associated with increased 30-day booster vaccine uptake in ED patients. Aim 3: To compare vaccine uptake (during the index ED visit and 30 days post visit) between sites that have COVID-19 booster vaccine available and those that do not. Aim 3a: To compare vaccine acceptance and 30-day uptake among patients with health insurance versus those without health insurance (evaluating the effects of patient vaccine cost on acceptance and uptake). Aim 4: To compare COVID-19 vaccine uptake in this current study with data gathered in our previous COVID-19 vaccine messaging trial. General Design: This is a three-arm cluster-randomized controlled trial (CRCT).

Interventions

BEHAVIORALVaccine Messaging

1. Video clips - short (approximately 3-minute) Public Service Announcement type videos to be viewed by participant using a QR code on their smartphone. If no smartphone is available, the video will be shown to the participant on an iPad. 2. Printed materials - one page information sheets handed to subjects by CRCs. 3. Face to face messaging - short (\< 1 minute), scripted message from the patient's providers in the ED (nurse or provider) Each site will maintain a library of A. 5 versions of the videos - the version used in any participant will be tailored to that participant's stated race/ethnicity. B. 5 versions of printed flyers - likewise, the version will be tailored to the participant's stated race/ethnicity. C. 1 version of scripted message to be delivered in English or Spanish.

BEHAVIORALVaccine Acceptance Question

The last question in the Vaccine Acceptance Survey in both the Intervention M and Intervention Q arms of the study is Would you accept the COVID-19 booster vaccine in the emergency department today if your doctor asked you?

Sponsors

National Institute of Allergy and Infectious Diseases (NIAID)
CollaboratorNIH
Pfizer
CollaboratorINDUSTRY
Duke University
CollaboratorOTHER
Baylor College of Medicine
CollaboratorOTHER
Thomas Jefferson University
CollaboratorOTHER
University of California, San Francisco
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
HEALTH_SERVICES_RESEARCH
Masking
SINGLE (Outcomes Assessor)

Masking description

Outcomes will be assessed at 30 days via EHR review or follow up phone call. EHR review and follow up calls will be conducted in a blinded fashion - the research staff person reviewing outcomes will be unaware of participant's study group assignment.

Intervention model description

PROBOOSTVAXED has 3 arms: Intervention M (Messaging + Vaccine Question) * Vaccine messaging given * Vaccine acceptance question asked Intervention Q (Vaccine Question, No Messaging) * No vaccine messaging * Vaccine acceptance question asked Control (No Messaging, No Vaccine Question) * No vaccine messaging * No vaccine acceptance question

Eligibility

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

Inclusion criteria

1. Age \> 18 years 2. Presenting to ED 3. No receipt of COVID-19 booster within prior 6 months 4. Able to provide informed consent 5. Fluent in English or Spanish 6. Anticipated ability to complete study intervention in ED i.e., able to watch a 3-minute videoclip

Exclusion criteria

1. Major trauma such that it will preclude survey 2. Inability to participate in a survey because of intoxication, altered mental status, or critical illness 3. Incarceration 4. Psychiatric hold 5. Patients who state that they have already received a bivalent COVID-19 booster vaccine or other COVID-19 vaccine within the prior 6 months 6. Patients who are in the ED for suspected acute COVID-19

Design outcomes

Primary

MeasureTime frameDescription
Number of Participants With 30-day Booster Vaccine Uptake30 daysOur primary outcome is booster vaccine uptake (at any vaccination location) within 30 days after participants' index ED visit, comparing Intervention M arm with Control

Secondary

MeasureTime frameDescription
Number or Participants Receiving Booster Vaccination in the EDday of index visitBooster vaccine uptake in the ED on the day of the index visit, M arm versus control and Q arm versus control
Number of Participants Stating They Would Accept Vaccine in the EDon the day of index ED visitA response of yes to the question, Would you accept the booster vaccine in the emergency department today if your doctor asked you?), comparing M and Q arms
Number of Participants With 30-day Booster Vaccine Uptake, Q Arm30 daysBooster vaccine uptake (at any vaccination location) within 30 days after participants' index ED visit, comparing Intervention Q arm with Control

Countries

United States

Participant flow

Pre-assignment details

919 participants were randomized

Participants by arm

ArmCount
PROBOOSTVAXED Intervention M (Messaging + Vaccine Question)
* Vaccine messaging * Vaccine acceptance question Vaccine Messaging: 1) Video clips - short (approximately 3-minute) Public Service Announcement type videos to be viewed by participant using a QR code on their smartphone. If no smartphone is available, the video will be shown to the participant on an iPad. 2\) Printed materials - one page information sheets handed to subjects by CRCs. 3) Face to face messaging - short (\< 1 minute), scripted message from the patient's providers in the ED (nurse or provider) Each site will maintain a library of A. 5 versions of the videos - the version used in any participant will be tailored to that participant's stated race/ethnicity. B. 5 versions of printed flyers - likewise, the version will be tailored to the participant's stated race/ethnicity. C. 1 version of scripted message to be delivered in English or Spanish. Vaccine Acceptance Question: The last question in the Vaccine Acceptance Survey in both the Intervention M and Intervention Q arms of the study is Would you accept the COVID-19 booster vaccine in the emergency department today if your doctor asked you?
247
Intervention Q (Vaccine Question, No Messaging)
* No vaccine messaging * Vaccine acceptance question asked in the Vaccine Acceptance Survey Vaccine Acceptance Survey: We will administer the Vaccine Acceptance Survey at some time (generally 30 minutes but up to 3 hours) after the Intake Survey. The surveys in the control group retain the same key primary and secondary outcome questions as in the intervention group Vaccine Acceptance surveys. Vaccine Acceptance Question: The last question in the Vaccine Acceptance Survey in both the Intervention M and Intervention Q arms of the study is Would you accept the COVID-19 booster vaccine in the emergency department today if your doctor asked you?
273
Control (No Messaging, No Vaccine Question)
* No vaccine messaging * No vaccine acceptance question The workflow during this arm is identical to the Intervention Q arm except there will be no Vaccine Acceptance Question survey.
332
Total852

Withdrawals & dropouts

PeriodReasonFG000FG001FG002FG003FG004FG005
Overall StudyBecame or found ineligible202012
Overall StudyLeft ED without completing study9390816
Overall StudyPhysician Decision100000
Overall StudyWithdrawal by Subject244022

Baseline characteristics

CharacteristicIntervention Q (Vaccine Question, No Messaging)PROBOOSTVAXED Intervention M (Messaging + Vaccine Question)TotalControl (No Messaging, No Vaccine Question)
Age, Continuous49 years46 years46.5 years46 years
Race/Ethnicity, Customized
American Indian, Alaska Native
0 Participants3 Participants5 Participants2 Participants
Race/Ethnicity, Customized
Asian
20 Participants12 Participants48 Participants16 Participants
Race/Ethnicity, Customized
Black
85 Participants83 Participants287 Participants119 Participants
Race/Ethnicity, Customized
Latinx
61 Participants48 Participants170 Participants61 Participants
Race/Ethnicity, Customized
Middle Eastern
0 Participants0 Participants0 Participants0 Participants
Race/Ethnicity, Customized
Native hawaiian/ Pacific Islander
4 Participants4 Participants12 Participants4 Participants
Race/Ethnicity, Customized
Other
8 Participants6 Participants24 Participants10 Participants
Race/Ethnicity, Customized
White (non-Latinx)
107 Participants101 Participants345 Participants137 Participants
Region of Enrollment
United States
273 participants247 participants852 participants332 participants
Sex/Gender, Customized
Man
129 Participants107 Participants379 Participants143 Participants
Sex/Gender, Customized
Other
2 Participants4 Participants9 Participants3 Participants
Sex/Gender, Customized
Woman
142 Participants136 Participants464 Participants186 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
EG002
affected / at risk
deaths
Total, all-cause mortality
0 / 2470 / 2730 / 332
other
Total, other adverse events
0 / 2470 / 2730 / 332
serious
Total, serious adverse events
0 / 2470 / 2730 / 332

Outcome results

Primary

Number of Participants With 30-day Booster Vaccine Uptake

Our primary outcome is booster vaccine uptake (at any vaccination location) within 30 days after participants' index ED visit, comparing Intervention M arm with Control

Time frame: 30 days

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
PROBOOSTVAXED Intervention M (Messaging + Vaccine Question)Number of Participants With 30-day Booster Vaccine Uptake14 Participants
Control (No Messaging, No Vaccine Question)Number of Participants With 30-day Booster Vaccine Uptake10 Participants
Secondary

Number of Participants Stating They Would Accept Vaccine in the ED

A response of yes to the question, Would you accept the booster vaccine in the emergency department today if your doctor asked you?), comparing M and Q arms

Time frame: on the day of index ED visit

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
PROBOOSTVAXED Intervention M (Messaging + Vaccine Question)Number of Participants Stating They Would Accept Vaccine in the ED73 Participants
Control (No Messaging, No Vaccine Question)Number of Participants Stating They Would Accept Vaccine in the ED90 Participants
Secondary

Number of Participants With 30-day Booster Vaccine Uptake, Q Arm

Booster vaccine uptake (at any vaccination location) within 30 days after participants' index ED visit, comparing Intervention Q arm with Control

Time frame: 30 days

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
PROBOOSTVAXED Intervention M (Messaging + Vaccine Question)Number of Participants With 30-day Booster Vaccine Uptake, Q Arm11 Participants
Control (No Messaging, No Vaccine Question)Number of Participants With 30-day Booster Vaccine Uptake, Q Arm10 Participants
Secondary

Number or Participants Receiving Booster Vaccination in the ED

Booster vaccine uptake in the ED on the day of the index visit, M arm versus control and Q arm versus control

Time frame: day of index visit

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
PROBOOSTVAXED Intervention M (Messaging + Vaccine Question)Number or Participants Receiving Booster Vaccination in the ED8 Participants
Control (No Messaging, No Vaccine Question)Number or Participants Receiving Booster Vaccination in the ED7 Participants
Control (No Messaging, No Vaccine Question)Number or Participants Receiving Booster Vaccination in the ED0 Participants

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