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NCT03880838 · ClinicalTrials.gov registry record · NA
Evaluation of a Letter Intervention Promoting a Plant-based Diet
A NA study, sponsored by Geisinger Clinic.
- Completed
- Registry status
- NA
- Development phase
- 11,234
- Enrollment target
NCT03880838: Completed NA study, sponsored by Geisinger Clinic.
NCT03880838 is a NA study that has completed, run by Geisinger Clinic. The registered enrollment target is 11,234 participants, above the 1,403-participant average among 58,714 other NA trials with a reported enrollment target (701% higher). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT03880838, a NA study, has completed, sponsored by Geisinger Clinic.
- COMPLETED
- Registry status
- NA
- Development phase
- 11,234 participants
- Enrollment target
Study Summary
The researchers' mission is to promote healthier eating behavior and to reduce costs associated with healthcare. The purpose of this study is to evaluate the effects of mailing randomly selected participants a letter promoting a plant-based diet. Depending on the experimental condition, participants may additionally receive a free documentary, Forks Over Knives, and they may also get letters which use commitment- or prevention-focused messages to encourage watching the documentary and changing their eating behavior. The researchers hypothesize that receiving the documentary will be associated with lower insurance claims and improved health outcomes one and two years later. The researchers also hypothesize that using either commitment- or prevention-focused messages will also contribute to lower insurance claims and improved health outcomes compared to experimental conditions where materials did not include these messages. This study will help the researchers design evidence-supported programs that can improve people's health.
Primary Outcome
Total annual amount of medical and pharmacy costs (sum) as reported by Geisinger Health Plan. General linear models are used to model change between the data from the year before the intervention and the data from one year after intervention. Lower costs is the desirable outcome.
Interventions
- BEHAVIORAL Personal testimonial
- BEHAVIORAL Forks Over Knives Documentary
- BEHAVIORAL Commitment nudge
- BEHAVIORAL Prevention nudge
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 11,234 participants |
| Start Date | 2019-06-20 |
| Est. Completion | 2022-06-30 |
| Phase | NA |
What the finished NCT03880838 record still lists
NCT03880838 is an interventional study that assigns participants to a tested intervention. Its 11,234 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 (701% higher).
The record links to 0 conditions, and to 4 interventions - of which Personal testimonial is the first listed.
NCT03880838 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT03880838 about?
NCT03880838 is a clinical study titled "Evaluation of a Letter Intervention Promoting a Plant-based Diet". The researchers' mission is to promote healthier eating behavior and to reduce costs associated with healthcare. The purpose of this study is to evaluate the effects of mailing randomly selected participants a letter promoting a plant-based diet. Depending on the experimental condition, participants...
What is the current status of trial NCT03880838?
This trial is currently completed. It is a NA study. The enrollment target is 11,234 participants. The study started on 2019-06-20. Estimated completion is 2022-06-30.
What interventions are being tested in trial NCT03880838?
The interventions under investigation include: Personal testimonial (BEHAVIORAL), Forks Over Knives Documentary (BEHAVIORAL), Commitment nudge (BEHAVIORAL), Prevention nudge (BEHAVIORAL).
Who is sponsoring clinical trial NCT03880838?
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 NCT03880838's enrollment target sits among peer trials
11,234 14th of 2000 higher than 1,987 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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