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NCT05648773 · ClinicalTrials.gov registry record · NA
COVID-19 Booster Incentives
A NA study of Booster Message and Booster Message + Financial Incentive, sponsored by University of Southern California.
- Completed
- Registry status
- NA
- Development phase
- 57,893
- Enrollment target
- 1
- Study location
NCT05648773: Completed NA study of Booster Message and Booster Message + Financial Incentive, sponsored by University of Southern California.
NCT05648773 is a NA study of Booster Message and Booster Message + Financial Incentive that has completed, run by University of Southern California. The registered enrollment target is 57,893 participants, above the 1,403-participant average among 58,714 other NA trials with a reported enrollment target (4026% higher). The trial reports 1 study location across 1 state. According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT05648773, a NA study of Booster Message and Booster Message + Financial Incentive, has completed, sponsored by University of Southern California.
- COMPLETED
- Registry status
- NA
- Development phase
- 57,893 participants
- Enrollment target
- 1
- Study location
Study Summary
The goal of this work is to understand whether small financial incentives and messaging can increase the take-up of COVID-19 boosters among patients empaneled at a county public health system. The motivation for this work is the relatively low take-up of COVID-19 boosters. In California, where our experiment is based, only 59% of the population has been boosted, with only 13% receiving the recommended bivalent booster (State of California, 2022).
Primary Outcome
Received a booster vaccination within 2-weeks of message.
Conditions Studied
Interventions
- OTHER Placebo
- BEHAVIORAL Financial Incentive
- BEHAVIORAL Messaging
Study Locations (1)
California
- Contra Costa Health Plan - Martinez
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 57,893 participants |
| Start Date | 2022-12-08 |
| Est. Completion | 2022-12-23 |
| Phase | NA |
What the finished NCT05648773 record still lists
NCT05648773 is an interventional study that assigns participants to a tested intervention. Its 57,893 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 (4026% higher).
The record links to 2 conditions, with Booster Message appearing as the primary indexed condition, and to 3 interventions - of which Placebo is the first listed.
NCT05648773 reports a single indexed study location in California.
Frequently Asked Questions
What is clinical trial NCT05648773 about?
NCT05648773 is a clinical study titled "COVID-19 Booster Incentives". The goal of this work is to understand whether small financial incentives and messaging can increase the take-up of COVID-19 boosters among patients empaneled at a county public health system. The motivation for this work is the relatively low take-up of COVID-19 boosters. In California, where our e...
What is the current status of trial NCT05648773?
This trial is currently completed. It is a NA study. The enrollment target is 57,893 participants. The study started on 2022-12-08. Estimated completion is 2022-12-23.
What conditions does trial NCT05648773 study?
This clinical trial studies the following conditions: Booster Message, Booster Message + Financial Incentive.
What interventions are being tested in trial NCT05648773?
The interventions under investigation include: Placebo (OTHER), Financial Incentive (BEHAVIORAL), Messaging (BEHAVIORAL).
Who is sponsoring clinical trial NCT05648773?
This trial is sponsored by University of Southern California, which has 617 total clinical trials registered on ClinicalTrials.gov.
Where is trial NCT05648773 being conducted?
This trial has 1 study location across California. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT05648773's enrollment target sits among peer trials
57,893 7th of 2000 higher than 1,994 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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