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NCT04801524 · ClinicalTrials.gov registry record · NA
Text-based Reminders to Promote COVID-19 Vaccinations
A NA study, sponsored by University of California, Los Angeles.
- Completed
- Registry status
- NA
- Development phase
- 250,000
- Enrollment target
NCT04801524: Completed NA study, sponsored by University of California, Los Angeles.
NCT04801524 is a NA study that has completed, run by University of California, Los Angeles. The registered enrollment target is 250,000 participants, above the 1,399-participant average among 58,714 other NA trials with a reported enrollment target (17770% higher). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT04801524, a NA study, has completed, sponsored by University of California, Los Angeles.
- COMPLETED
- Registry status
- NA
- Development phase
- 250,000 participants
- Enrollment target
Study Summary
This study investigates whether and which type of text-based reminders affect the take-up of the COVID-19 vaccine.
Primary Outcome
Whether patients schedule their vaccination appointment at UCLA Health within 6 days of receiving the second text message (including the day of text message). Specifically, if t=the date of the second text message (for the holdout arm, this refers to the date they would have received the text message had they not been assigned to the holdout arm), we will track vaccination appointments made by the end of t+5. While most people just make one appointment, a small percentage update their appointmen
Interventions
- BEHAVIORAL Self-benefit
- BEHAVIORAL Prosocial-benefit
- BEHAVIORAL Early access
- BEHAVIORAL Fresh start
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 250,000 participants |
| Start Date | 2021-02-07 |
| Est. Completion | 2022-01-01 |
| Phase | NA |
What the finished NCT04801524 record still lists
NCT04801524 is an interventional study that assigns participants to a tested intervention. Its 250,000 participants enrollment target places it among the larger protocols in the corpus, above the 1,399-participant average among 58,714 other NA trials with a reported enrollment target (17770% higher).
The record links to 0 conditions, and to 4 interventions - of which Self-benefit is the first listed.
NCT04801524 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT04801524 about?
NCT04801524 is a clinical study titled "Text-based Reminders to Promote COVID-19 Vaccinations". This study investigates whether and which type of text-based reminders affect the take-up of the COVID-19 vaccine.
What is the current status of trial NCT04801524?
This trial is currently completed. It is a NA study. The enrollment target is 250,000 participants. The study started on 2021-02-07. Estimated completion is 2022-01-01.
What interventions are being tested in trial NCT04801524?
The interventions under investigation include: Self-benefit (BEHAVIORAL), Prosocial-benefit (BEHAVIORAL), Early access (BEHAVIORAL), Fresh start (BEHAVIORAL).
Who is sponsoring clinical trial NCT04801524?
This trial is sponsored by University of California, Los Angeles, which has 897 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT04801524's enrollment target sits among peer trials
250,000 1st of 2000 higher than 2,000 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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