Clinical trial NCT04160975: Persuasion in Medicine: Experimental Evidence on Sender and Signal Effects
Official title: Persuasion in Medicine: Experimental Evidence on Sender and Signal Effects
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Flu, Human
Influenza, Human
Covid19
Keywords: Belief Updating
Preventive Care
Racial Disparity
Lead sponsor: Harvard University
Sponsor class: OTHER
Collaborators: name: Ludwig-Maximilians - University of Munich
name: Massachusetts Institute of Technology
name: National Institute on Aging (NIA)
First posted: 2019-11-13
Enrollment: 3245
Sex: MALE
Minimum age (years): 18
Maximum age (years): 51
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: HEALTH_SERVICES_RESEARCH

Brief 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.

Detailed description: The investigators will recruit approximately 3350 African-American or Caucasian adult males with a high-school diploma or less. A pilot study, which ran during the 2019-20 flu season, recruited approximately 850 subjects, and a planned scale-up will recruit an additional 2500 subjects during the 2020-21 flu season. The investigators will oversample African American individuals, emphasizing low-income and minority men because these characteristics are correlated with lower relative take-up of flu vaccination. After informed consent is obtained, subjects will be asked about sociodemographic information (age, education, income and marital status), healthcare experience and past medical history, knowledge and beliefs about flu vaccination, and location of the nearest pharmacy. The investigators will then randomly assign the adult male subjects to videos which contain one of Black or white actors playing the role of either a doctor or a layperson as well as different scripts. The content of the infomercial will be the safety and effectiveness of adult seasonal flu vaccination. After the video, the investigators will obtain information on beliefs regarding vaccination, feedback on the video, attention to the video and willingness-to-pay for a flu shot coupon. The final baseline module will consist of a randomly assigned invitation to receive the results of an upcoming review of a COVID-19 vaccine, with subjects assigned to receive information from a trusted or standard source. The investigators will track flu coupon redemption, which is redeemable at most pharmacies nationwide.

Eligibility criteria: Inclusion Criteria:

* Age: See above.
* Education: Less than a college degree.
* Gender: Male.
* Race: Caucasian or African American.
* Miscellaneous: Has not received the flu shot in the current flu season yet.
* Miscellaneous: Has sound on his device turned on.

Exclusion Criteria:

* Fast survey-taking: subjects who are among the 5% fastest in terms of total time spent on survey within race and treatment group.
* Nonsense answers (those that do not have decipherable English) in the open text sections that suggest low effort.
* Inconsistent responses to questions (such as being willing to give up $10 to receive a flu coupon but not $1).
* Repeat survey takers as indicated by duplicate emails or IP addresses in survey data.

Primary outcomes:
measure: Rating of Sender
timeFrame: This outcome was assessed during Baseline survey, which took approximately 20 minutes.
measure: Rating of Signal
timeFrame: This outcome was assessed during Baseline survey, which took approximately 20 minutes.
measure: Signal Content Recall
timeFrame: This outcome will be assessed during Baseline survey, which takes approximately 20 minutes.
measure: Safety Beliefs
timeFrame: This outcome will be assessed during Baseline survey, which takes approximately 20 minutes.
measure: Coupon Interest
timeFrame: This outcome was assessed during Baseline survey, which took approximately 20 minutes.
measure: (Posterior) Flu Vaccine Intent
timeFrame: This outcome was assessed after the video treatment during Baseline survey, which took approximately 20 minutes.
measure: COVID-19 Vaccine Intent
timeFrame: This outcome was assessed after the video treatment during Baseline survey, which took approximately 20 minutes.
measure: Flu Vaccine Take-up
timeFrame: This outcome was assessed during the follow-up survey which was conducted at least two weeks after the initial baseline survey.
Secondary outcomes:
Other outcomes:
Locations:
city: Cambridge
country: United States
facility: Harvard University
state: Massachusetts
Study officials:
References: