The Minimal Effects of Public Health Campaigns on Travel During the COVID-19 Pandemic

Last registered on October 05, 2023
View Trial History

Pre-Trial

Trial Information

General Information

Title
The Minimal Effects of Public Health Campaigns on Travel During the COVID-19 Pandemic
RCT ID
AEARCTR-0012148
Initial registration date
September 19, 2023

Initial registration date is when the trial was registered.

It corresponds to when the registration was submitted to the Registry to be reviewed for publication.

First published
October 04, 2023, 12:55 PM EDT

First published corresponds to when the trial was first made public on the Registry after being reviewed.

Last updated
October 05, 2023, 10:50 AM EDT

Last updated is the most recent time when changes to the trial's registration were published.

Locations

Country
United States of America
Region
Cook County, IL

Primary Investigator

Name
Adam Zelizer
Affiliation
University of Chicago
Contact Primary Investigator

Other Primary Investigator(s)

PI Name
Ethan Bueno de Mesquita
PI Affiliation
Harris School of Public Policy
Contact Investigator
PI Name
Mehdi Shadmehr
PI Affiliation
University of North Carolina at Chapel Hill
Contact Investigator
PI Name
Benjamin Shaver
PI Affiliation
Harris School of Public Policy
Contact Investigator

Additional Trial Information

Status
Completed
Start date
2020-12-11
End date
2021-01-01
Keywords
Health
Additional Keywords
COVID-19; public health; social distancing
JEL code(s)
D01; D91; H12; H75; I12; I18
Secondary IDs
Prior work
This trial does not extend or rely on any prior RCTs.
Abstract
Governments and public health experts have used mass media campaigns to limit the spread of COVID-19 by encouraging social distancing. This paper explores the effectiveness of a health campaign via a large-scale field experiment conducted in Cook County, Illinois. In December 2020, approximately 125,000 households were sent mail from the University of Chicago Medicine encouraging social distancing during the holiday season. Within targeted geographies, we varied both the dosage of treatments as well as publicity --- whether recipients were informed that their neighbors also received the messages --- to highlight the strategic considerations underlying social distancing. We find minimal effects of the campaign on travel during the holidays and on other social distancing behavior. We consider our results in light of a similar intervention reported in Breza et al (2021) and conclude that travel was unlikely to be influenced by messages from public health experts prior to the 2020 holiday season.
External Link(s)

Registration Citation

Citation
Zelizer, Adam et al. 2023. "The Minimal Effects of Public Health Campaigns on Travel During the COVID-19 Pandemic." AEA RCT Registry. October 05. https://doi.org/10.1257/rct.12148-1.1
Sponsors & Partners

There is information in this trial unavailable to the public. Use the button below to request access.

Request Information
Experimental Details

Interventions

Intervention(s)
In December 2020, approximately 125,000 households were sent mail from the University of Chicago Medicine encouraging social distancing during the holiday season. Within targeted geographies, we varied both the dosage of treatments as well as publicity --- whether recipients were informed that their neighbors also received the messages --- to highlight the strategic considerations underlying social distancing.
Intervention Start Date
2020-12-11
Intervention End Date
2021-01-01

Primary Outcomes

Primary Outcomes (end points)
Key outcomes include measures of social distancing. We collected two measures: a survey fielded via telephone in January 2021 and cell phone-based mobility data acquired from a commercial vendor.
Primary Outcomes (explanation)
Survey measures of social distancing include questions about congregating over the holidays, going to bars or restaurants; and shopping in-person or online.

Secondary Outcomes

Secondary Outcomes (end points)
Secondary Outcomes (explanation)

Experimental Design

Experimental Design
Mailers were sent to residents of Cook County, Illinois. We obtained contact information for the 4.4 million adults residing in Cook County from a private data vendor. Nearly all residents had valid addresses, while slightly less than half had phone numbers. To avoid sending multiple mailers to the same household, we randomly selected one adult per household to receive the mailer and be called for the survey.

The unit of treatment assignment was the Census Block Group (CBG). Cook County has approximately 4,000 CBGs, which range in size from one household to nearly 3,800. To improve statistical power and optimize our budget, we dropped particularly small and large CBGs from the study. Our population consists of the 3,600 CBGs with between 98 and 799 households. This sample covers nearly 3.6 million people. 100 CBGs were randomly assigned to each of the four treatment arms. We clustered treatment assignment at this level because one of our outcome measures, cell phone tracking data, is aggregated at the CBG-level.
Experimental Design Details
Randomization Method
Randomization done in office by a computer
Randomization Unit
Census block group.
Was the treatment clustered?
Yes

Experiment Characteristics

Sample size: planned number of clusters
3600
Sample size: planned number of observations
3600
Sample size (or number of clusters) by treatment arms
100 block groups to each of the treatment arms: 50% dosage public; 50% dosage private; 100% dosage public; 100% dosage private.
Minimum detectable effect size for main outcomes (accounting for sample design and clustering)
Supporting Documents and Materials
IRB

Institutional Review Boards (IRBs)

IRB Name
University of Chicago SBS-IRB
IRB Approval Date
2020-04-06
IRB Approval Number
IRB20-0575
Analysis Plan

Post-Trial

Post Trial Information

Study Withdrawal

There is information in this trial unavailable to the public. Use the button below to request access.

Request Information

Intervention

Is the intervention completed?
No
Data Collection Complete
Data Publication

Data Publication

Is public data available?
No

Program Files

Program Files
Reports, Papers & Other Materials

Relevant Paper(s)

Reports & Other Materials