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NCT04728594 · ClinicalTrials.gov registry record · NA
Emails Promoting COVID-19 Vaccination Among Healthcare Workers
A NA study, sponsored by Geisinger Clinic.
- Completed
- Registry status
- NA
- Development phase
- 9,566
- Enrollment target
NCT04728594: Completed NA study, sponsored by Geisinger Clinic.
NCT04728594 is a NA study that has completed, run by Geisinger Clinic. The registered enrollment target is 9,566 participants, above the 1,403-participant average among 58,714 other NA trials with a reported enrollment target (582% higher). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT04728594, a NA study, has completed, sponsored by Geisinger Clinic.
- COMPLETED
- Registry status
- NA
- Development phase
- 9,566 participants
- Enrollment target
Study Summary
In this evaluation, two versions of emails will be sent to Geisinger employees who have not been vaccinated against COVID-19. A delayed-contact control group will be emailed after a delay of at least two days. The researchers hypothesize that either of the emails - which use content informed by behavioral nudge theory - will lead to more COVID-19 vaccinations than the delayed-contact control group.
Primary Outcome
Binary variable of a scheduled vaccination appointment 3 days after the emails were sent
Interventions
- BEHAVIORAL Social Proof
- BEHAVIORAL Reframing
- BEHAVIORAL Scarcity Message
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 9,566 participants |
| Start Date | 2021-01-15 |
| Est. Completion | 2021-01-20 |
| Phase | NA |
What the finished NCT04728594 record still lists
NCT04728594 is an interventional study that assigns participants to a tested intervention. Its 9,566 participants enrollment target places it among the larger protocols in the corpus, above the 1,403-participant average among 58,714 other NA trials with a reported enrollment target (582% higher).
The record links to 0 conditions, and to 3 interventions - of which Social Proof is the first listed.
NCT04728594 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT04728594 about?
NCT04728594 is a clinical study titled "Emails Promoting COVID-19 Vaccination Among Healthcare Workers". In this evaluation, two versions of emails will be sent to Geisinger employees who have not been vaccinated against COVID-19. A delayed-contact control group will be emailed after a delay of at least two days. The researchers hypothesize that either of the emails - which use content informed by beha...
What is the current status of trial NCT04728594?
This trial is currently completed. It is a NA study. The enrollment target is 9,566 participants. The study started on 2021-01-15. Estimated completion is 2021-01-20.
What interventions are being tested in trial NCT04728594?
The interventions under investigation include: Social Proof (BEHAVIORAL), Reframing (BEHAVIORAL), Scarcity Message (BEHAVIORAL).
Who is sponsoring clinical trial NCT04728594?
This trial is sponsored by Geisinger Clinic, which has 107 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT04728594's enrollment target sits among peer trials
9,566 16th of 2000 higher than 1,985 of 2,000 other NA trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other NA trials. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source ClinicalTrials.gov registry export · 2026-08-08
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