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NCT04160975 · ClinicalTrials.gov registry record · NA

Persuasion in Medicine: Experimental Evidence on Sender and Signal Effects

A NA study, sponsored by Harvard University.

Completed
Registry status
NA
Development phase
3,245
Enrollment target

NCT04160975: Completed NA study, sponsored by Harvard University.

NCT04160975 is a NA study that has completed, run by Harvard University. The registered enrollment target is 3,245 participants, above the 1,404-participant average among 58,714 other NA trials with a reported enrollment target (131% higher). According to ClinicalTrials.gov, the official US trial registry.

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The verdict

NCT04160975, a NA study, has completed, sponsored by Harvard University.

COMPLETED
Registry status
NA
Development phase
3,245 participants
Enrollment target

Study Summary

The aim of the study is to identify what sender/signal combinations are most persuasive in encouraging low socioeconomic males living in the U.S. to take-up seasonal flu vaccination. The investigators plan to recruit male subjects and randomly assign them to four persuasion treatments: three of which vary dimensions of the sender of a medical recommendation (racial concordance and authority treatments) and one which varies the signal (standard vs. empathetic). Specifically, the investigators will show subjects videos of either Black or white actors/actresses providing scripted information on the flu vaccination. The investigators will randomize the race of the sender and if the subject is Black, also randomize the authority of the sender, with the actor portraying either a doctor or a layperson. In addition, the investigators will vary the script used in the experiment between one that acknowledges past injustices (indicated as an empathetic script hereafter) and one that does not (indicated as a standard script hereafter). The investigators will provide subjects a free flu shot coupon and elicit the price at which subjects would be willing to give up this coupon for a cash reward. Lastly, in light of the relevance of vaccination take-up in combating COVID-19 pandemic, the investigators will assess demand for information about a COVID-19 vaccine, with subjects invited to receive results of a safety and efficacy review from a trusted or standard source. The design requires the collection of baseline and endline surveys combined with administrative data from pharmacies about coupon redemption. The primary outcomes of interest are posterior beliefs about seasonal flu vaccination, demand and willingness-to-pay (WTP) for a free flu shot coupon, redemption of the coupon, and demand for information about a COVID-19 vaccine.

Primary Outcome

This is an inverse-covariance-weighted index comprised of responses to survey questions regarding: 1. whether the respondent was interested in further medical advice from the given sender (measured as a binary outcome); 2. whether the respondent trusted advice from the sender measured on a scale of 1 to 5; 3. and whether the respondent's assessment of the sender's qualification to provide medical advice measured on a scale of 1 to 5. It is standardized to a mean of 0 and standard deviation of

Interventions

  • BEHAVIORAL Video about safety and effectiveness of adult seasonal flu vaccination

Trial Details

FieldValue
Enrollment Target 3,245 participants
Start Date 2019-12-20
Est. Completion 2021-02-19
Phase NA
Harvard University

37 total trials

What the finished NCT04160975 record still lists

NCT04160975 is an interventional study that assigns participants to a tested intervention. Its 3,245 participants enrollment target places it among the larger protocols in the corpus, above the 1,404-participant average among 58,714 other NA trials with a reported enrollment target (131% higher).

The record links to 0 conditions, and to 1 intervention - of which Video about safety and effectiveness of adult seasonal flu vaccination is the first listed.

NCT04160975 does not publish any study locations in the registry export this page uses.

Frequently Asked Questions

What is clinical trial NCT04160975 about?

NCT04160975 is a clinical study titled "Persuasion in Medicine: Experimental Evidence on Sender and Signal Effects". The aim of the study is to identify what sender/signal combinations are most persuasive in encouraging low socioeconomic males living in the U.S. to take-up seasonal flu vaccination. The investigators plan to recruit male subjects and randomly assign them to four persuasion treatments: three of whic...

What is the current status of trial NCT04160975?

This trial is currently completed. It is a NA study. The enrollment target is 3,245 participants. The study started on 2019-12-20. Estimated completion is 2021-02-19.

What interventions are being tested in trial NCT04160975?

The interventions under investigation include: Video about safety and effectiveness of adult seasonal flu vaccination (BEHAVIORAL).

Who is sponsoring clinical trial NCT04160975?

This trial is sponsored by Harvard University, which has 37 total clinical trials registered on ClinicalTrials.gov.

How this trial's enrollment target compares

Where NCT04160975's enrollment target sits among peer trials

3,245 37th of 2000 higher than 1,964 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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Source: ClinicalTrials.gov NCT04160975, the US trial registry maintained by the National Library of Medicine. NCT04160975 (large enrollment · none site footprint · completed) retrieved and formatted by PlainTrial, see methodology.