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NCT04533685 · ClinicalTrials.gov registry record · NA
Patient Portal Reminder/Recall for Influenza Vaccination in a Health System- UCLA Portal R/R Influenza RCT 3
A NA study, sponsored by University of California, Los Angeles.
- Completed
- Registry status
- NA
- Development phase
- 213,773
- Enrollment target
NCT04533685: Completed NA study, sponsored by University of California, Los Angeles.
NCT04533685 is a NA study that has completed, run by University of California, Los Angeles. The registered enrollment target is 213,773 participants, above the 1,400-participant average among 58,714 other NA trials with a reported enrollment target (15170% higher). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT04533685, a NA study, has completed, sponsored by University of California, Los Angeles.
- COMPLETED
- Registry status
- NA
- Development phase
- 213,773 participants
- Enrollment target
Study Summary
This trial is taking place in Los Angeles, CA among patients from primary care practices within the UCLA Health System. The study design is a 2x2x2 factorial design, nested in a parallel 2-arm trial. The parallel arms are control v. reminder letter (reminder messages sent via the patient portal, reminding participants of an overdue influenza vaccine) Nested within the reminder letter arm, we will have 3 additional components: * A direct scheduling link within the reminder letter enabling the patient to schedule an influenza vaccine only visit (direct scheduling link vs. no direct scheduling link). * A pre-commitment prompt (pre-commitment prompt vs. no prompt) asking about a patient's intention to get the influenza vaccination * A pre-appointment reminder, encouraging patients to ask for their influenza vaccine at their upcoming appointment (pre-appointment reminder encouraging influenza vaccination vs. standard pre-appointment reminder not mentioning influenza vaccination)
Primary Outcome
Receipt of the annual influenza vaccination (between 8/1/20 - 4/1/21) among index patients. Outcomes will be assessed via vaccine data extraction from the electronic health record and external claims and pharmacy data. The index patients must also be an active UCLA Health MyChart user (\>= 1 login over the last 12 months from 8/1/20, excluding activity on the user's initial profile activation date). Individuals not affiliated with any primary care practice will be excluded from the primary anal
Interventions
- BEHAVIORAL Portal Reminders for Influenza Vaccination: Direct scheduling link
- BEHAVIORAL Portal Reminders for Influenza Vaccination: No direct scheduling link
- BEHAVIORAL Pre-Commitment Prompt
- BEHAVIORAL Pre-Appointment flu vaccine reminders
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 213,773 participants |
| Start Date | 2020-09-01 |
| Est. Completion | 2021-04-01 |
| Phase | NA |
What the finished NCT04533685 record still lists
NCT04533685 is an interventional study that assigns participants to a tested intervention. Its 213,773 participants enrollment target places it among the larger protocols in the corpus, above the 1,400-participant average among 58,714 other NA trials with a reported enrollment target (15170% higher).
The record links to 0 conditions, and to 4 interventions - of which Portal Reminders for Influenza Vaccination: Direct scheduling link is the first listed.
NCT04533685 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT04533685 about?
NCT04533685 is a clinical study titled "Patient Portal Reminder/Recall for Influenza Vaccination in a Health System- UCLA Portal R/R Influenza RCT 3". This trial is taking place in Los Angeles, CA among patients from primary care practices within the UCLA Health System. The study design is a 2x2x2 factorial design, nested in a parallel 2-arm trial. The parallel arms are control v. reminder letter (reminder messages sent via the patient portal, re...
What is the current status of trial NCT04533685?
This trial is currently completed. It is a NA study. The enrollment target is 213,773 participants. The study started on 2020-09-01. Estimated completion is 2021-04-01.
What interventions are being tested in trial NCT04533685?
The interventions under investigation include: Portal Reminders for Influenza Vaccination: Direct scheduling link (BEHAVIORAL), Portal Reminders for Influenza Vaccination: No direct scheduling link (BEHAVIORAL), Pre-Commitment Prompt (BEHAVIORAL), Pre-Appointment flu vaccine reminders (BEHAVIORAL).
Who is sponsoring clinical trial NCT04533685?
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 NCT04533685's enrollment target sits among peer trials
213,773 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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