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Completed Not applicable Interventional Results available

Use of Construal Level Theory to Inform Messaging to Increase Vaccination Against COVID-19

ClinicalTrials.gov ID: NCT04871776

Public ClinicalTrials.gov record NCT04871776. Field values are reproduced from the official study page; the official ClinicalTrials.gov record remains the source of truth for eligibility, enrollment, and contact information.

ClinicalTrials.gov public records Last synced Sep 6, 2026, 2:49 PM EDT

Data is sourced from official ClinicalTrials.gov public API records. Always review the official ClinicalTrials.gov record for the latest information.

Brief summary

Reproduced verbatim from the official ClinicalTrials.gov record. Not medical advice.

This study aims to increase uptake of the COVID booster vaccine through messaging informed by Construal Level Theory. Patients in the Mass General Brigham (MGB) health system aged 18 and older who are eligible for the COVID booster vaccine, but who have not yet received a dose at the time of an upcoming primary care clinic visit, will be randomized to one of three messaging arms: 1) "why" messaging, 2) "how" messaging, or 3) standard of care ("usual care"). Messages will be sent via the electronic patient portal a few days in advance of their office visit. The primary outcome will be the rate of booster vaccination at the targeted visit. The secondary outcome will be the rate of receipt of a COVID booster vaccine within 6 weeks of the targeted visit. Subgroup analyses to assess for any association of patient characteristics with intervention responsiveness will be exploratory.

Study identification

NCT ID
NCT04871776
Recruitment status
Completed
Study type
Interventional
Phase
Not applicable
Enrollment
3,671 participants

Conditions and interventions

Eligibility (public fields only)

Age range
18 Years and older
Sex
All
Healthy volunteers
Healthy volunteers not accepted

This page does not interpret eligibility. Detailed inclusion and exclusion criteria are on the official ClinicalTrials.gov record.

Study timeline

Start date
Feb 17, 2022
Primary completion
May 26, 2022
Completion
Aug 16, 2022
Last update posted
Jan 15, 2024

2022

United States locations

U.S. sites
1
U.S. states
1
U.S. cities
1
Facility City State ZIP Site status
Mass General Brigham Boston Massachusetts 02120

Site contact phone numbers, emails, and investigator names are intentionally not displayed here. Open the official ClinicalTrials.gov record for site contact information.

About this trial record page

What this page shows
Public field values for ClinicalTrials.gov record NCT04871776, including study identification, conditions, interventions, eligibility (age, sex, healthy volunteer), timeline, and U.S. site list.
What this page does not do
No medical advice, eligibility judgments, treatment recommendations, study quality scoring, or AI-generated medical summaries. No site contact phone numbers, emails, or investigator names.
Where the data comes from
Sourced from the official ClinicalTrials.gov public API. The official record is the source of truth.
Last refresh
Last update posted Jan 15, 2024 · Synced Sep 6, 2026

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Open the official record

The complete protocol, eligibility criteria, and contact information for NCT04871776 live on ClinicalTrials.gov.

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