Emails Promoting COVID-19 Vaccination Among Healthcare Workers

Evaluation of an Email Intervention Promoting COVID-19 Vaccination Among Healthcare Workers

In this evaluation, two versions of emails will be sent to Geisinger employees who have not been vaccinated against COVID-19. A delayed-contact control group will be emailed after a delay of at least two days. The researchers hypothesize that either of the emails - which use content informed by behavioral nudge theory - will lead to more COVID-19 vaccinations than the delayed-contact control group.

Study Overview

• Status: Completed
• Conditions: Communication; Vaccination Refusal
• Intervention / Treatment: Behavioral: Social Proof; Behavioral: Scarcity Message; Behavioral: Reframing

Detailed Description

The researchers aim to evaluate the effectiveness of email reminders in promoting COVID-19 vaccinations among Geisinger employees. The project will compare two emails, which will vary in the subject line and email content. Both emails will test different approaches that draw from principles in behavioral science: social proof, reframing, and scarcity. Employees receiving these emails will be compared with employees in a delayed-contact group, who will not receive emails. Employees in the control group will later receive one of the emails.The responses to the emails will help determine the communications later sent to the control group.

All emails will ask recipients if they want to receive a COVID-19 vaccination. If they click on a hyperlink indicating yes, they will be forwarded to an online registration and scheduling homepage. If they click on a hyperlink indicating no, they will be forwarded to an online questionnaire surveying people about their main reason for declining the vaccine at this time. The questionnaire will automatically present information intended to assuage the specific concern that people endorse, followed by a hyperlink to the scheduling site.

The data will be analyzed with logistic regression models with the control group as the reference group, to compare the two email conditions versus the control group. This set of analyses will only be conducted for scheduling a vaccination appointment as opposed to email engagement outcomes (e.g., number of emails opened), which will not be applicable for the control group. A second set of logistic regression models predicting scheduling a vaccination appointment and email engagement will also be run, comparing the two email conditions against each other. The data will be examined two days later (to help decide which email to send to the delayed-control group) and four days later (when the policy for employee vaccination will change, making the content of the email irrelevant).

Update: The researchers looked at 3 days of data - as the emails to the delayed contact group were only sent at that time - and 4 days of data when the policy for employee vaccinations changed.

• Study Type: Interventional
• Enrollment (Actual): 9566
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Pennsylvania
    • Danville, Pennsylvania, United States, 17822
      • Geisinger

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Employees at Geisinger Health System who have not gotten a COVID-19 vaccination

Exclusion Criteria:

• None

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
No Intervention: Delayed Contact; This group will not receive an email for at least two days.
Experimental: Social Proof; This group will receive an email that points out that vaccine availability for employees will soon be limited. It also emphasizes how many fellow health care workers have been vaccinated. Seeing the behaviors of other people might encourage recipients to copy that behavior.	Behavioral: Social Proof; Email; Behavioral: Scarcity Message; Email
Experimental: Reframing Side Effects and Adverse Reactions; This group will receive an email that points out that vaccine availability for employees will soon be limited. It also addresses concerns about the side effects and adverse reactions of the vaccine. Due to potentially overblown concerns about the vaccine caused by the salience of side effects in the (social) media, the email attempts to reframe the risks by explicitly noting the small possibility of being affected by serious side effects and by contrasting that to the more severe effects of COVID-19. As a result of this reframing, recipients might recalibrate their perception of risks and benefits and opt for vaccination.	Behavioral: Scarcity Message; Email; Behavioral: Reframing; Email

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of Employees Who Scheduled Vaccination Appointments After 3 Days	Binary variable of a scheduled vaccination appointment 3 days after the emails were sent	3 days

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of Employees Who Opened Emails After 3 Days	Binary variable indicating whether the employee opened the email 3 days after the emails were sent	3 days
Number of Employees Who Clicked Scheduling Links After 3 Days	Binary variable indicating whether the employee clicked the link to schedule a vaccination appointment 3 days after the emails were sent	3 days

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of Employees Who Scheduled Vaccination Appointments Until Policy Change (4 Days)	Binary variable of a scheduled vaccination appointment up to the end of January 19, when new distribution policies were enacted.	4 days
Number of Employees Who Opened Emails Until Policy Change (4 Days)	Binary variable indicating whether the employee opened the email up to the end of January 19, when new distribution policies were enacted.	4 days
Number of Employees Who Clicked the Scheduling Link Until Policy Change (4 Days)	Binary variable indicating whether the employee clicked the link to schedule a vaccination appointment up to the end of January 19, when new distribution policies were enacted.	4 days

Collaborators and Investigators

• Sponsor: Geisinger Clinic
• Investigators: Principal Investigator: Michelle M Meyer, PhD, Geisinger Clinic

Publications and helpful links

General Publications

• Santos HC, Goren A, Chabris CF, Meyer MN. Effect of Targeted Behavioral Science Messages on COVID-19 Vaccination Registration Among Employees of a Large Health System: A Randomized Trial. JAMA Netw Open. 2021 Jul 1;4(7):e2118702. doi: 10.1001/jamanetworkopen.2021.18702.

Study record dates

Study Major Dates

• Study Start (Actual): January 15, 2021
• Primary Completion (Actual): January 17, 2021
• Study Completion (Actual): January 20, 2021

Study Registration Dates

• First Submitted: January 26, 2021
• First Submitted That Met QC Criteria: January 26, 2021
• First Posted (Actual): January 28, 2021

Study Record Updates

• Last Update Posted (Actual): July 26, 2021
• Last Update Submitted That Met QC Criteria: July 22, 2021
• Last Verified: July 1, 2021

More Information

Terms related to this study

• Keywords: Immunization; Psychology; Electronic Mail; Economics, Behavioral; Persuasive Communication
• Other Study ID Numbers: 2021-0128

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Data with no personally identifiable information will be made available to other researchers on the Open Science Framework for transparency. This will include the essential data and code needed to replicate the analysis that yielded reported findings.
• IPD Sharing Time Frame: The data will become available after publication of study results in a scientific journal and will be available as long as the Open Science Framework hosts the data.
• IPD Sharing Access Criteria: The data on the Open Science Framework will be open to anyone requesting that information.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; ANALYTIC_CODE

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No