Belief Updating, Risk Information, and Urban Flooding: A Field Experiment in Mozambique

Last registered on February 12, 2024
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Pre-Trial

Trial Information

General Information

Title
Belief Updating, Risk Information, and Urban Flooding: A Field Experiment in Mozambique
RCT ID
AEARCTR-0008451
Initial registration date
October 27, 2021

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 28, 2021, 10:45 AM EDT

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

Last updated
February 12, 2024, 10:16 AM EST

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

Locations

Country
Mozambique
Region
Zambezia

Primary Investigator

Name
Stefan Leeffers
Affiliation
University College London
Contact Primary Investigator

Other Primary Investigator(s)

Additional Trial Information

Status
Completed
Start date
2021-07-30
End date
2022-09-30
Keywords
Behavior, Environment & Energy, Gender
Additional Keywords
Risk communication, urban flooding, field experiment, Mozambique
JEL code(s)
C93, D83, D91, O12, Q54
Secondary IDs
Prior work
This trial does not extend or rely on any prior RCTs.
Abstract
This study investigates the impact of a disaster information campaign designed to raise flood risk perceptions and promote mitigation behavior among vulnerable urban households in Mozambique. The information campaign provided community leaders and households with contextualized, actionable information related to flood risk through videos shown during home visits and text messages. The project evaluates the effect of the interventions on perceptions and behavior, as well as how these changes in behavior reduce flooding and the impact of flooding.
External Link(s)

Registration Citation

Citation
Leeffers, Stefan. 2024. "Belief Updating, Risk Information, and Urban Flooding: A Field Experiment in Mozambique." AEA RCT Registry. February 12. https://doi.org/10.1257/rct.8451-5.1
Sponsors & Partners

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Experimental Details

Interventions

Intervention(s)
Videos
I designed two six-minute videos, a public officials video, and a flood victims video. The videos were incorporated into surveys with the target population, which took place from September to November 2021. Both videos contained the same information. The visuals in the videos alternate between the speakers, images, and video recordings that help convey the message. Publicly available images and recordings of local news outlets were used for this purpose. The same visuals were used in both videos. The standard Portuguese versions of the videos were also dubbed in Chuabo, the most common local language, to promote inclusiveness among all ages and education levels. In the public officials video, the information was delivered by local government officials (one man and one woman) responsible for disaster risk management. The flood victims video featured two residents (one man and one woman). These actors drew on their recent flooding experience to deliver the information. Finally, to measure the effectiveness of the interventions, I created a placebo video. This six-minute video contained general information about Quelimane, its history, and its main economic activities. This information was delivered by residents, contained images and video recordings, and was also made available in Chuabo.

Text messages
I designed a set of six text messages summarizing the key points of the videos. The text messages were sent daily to chiefs and households in selected city blocks from November 19 until November 24, 2021.

Please see the pre-analysis plan for more details.
Intervention (Hidden)
Intervention Start Date
2021-09-16
Intervention End Date
2021-11-24

Primary Outcomes

Primary Outcomes (end points)
Measurements include multiple sources of data: two rounds of surveys with households and chiefs and surveys conducted during the scale-up visiting of households, a behavioral experiment, behavioral measures based on SMS technology, pictures along drainage canals and at random locations across city blocks, and SAR satellite images. Please see the pre-analysis plan for more details.
Primary Outcomes (explanation)

Secondary Outcomes

Secondary Outcomes (end points)
Please see the pre-analysis plan for details.
Secondary Outcomes (explanation)

Experimental Design

Experimental Design
The 300 city blocks considered for follow-up data collection can be divided into 6 groups.
T0: The control group in which the chief and two households were shown the placebo video
T1: The text messages treatment in which the chief and about 30 percent of the households were shown the placebo video and received the treatment text messages.
T2: The public officials treatment in which the chief and two households were shown the public officials video
T3: The public officials (scale-up) treatment in which the chief and about 30 percent of the households were shown the public officials video and received the treatment text messages.
T4: The flood victims treatment in which the chief and two households were shown the flood victims video
T5: The flood victims (scale-up) treatment in which the chief and about 30 percent of the households were shown the flood victims video and received the treatment text messages.
Please see the pre-analysis plan for more details.
Experimental Design Details
Randomization Method
Please see the pre-analysis plan for details.
Randomization Unit
City blocks
Was the treatment clustered?
Yes

Experiment Characteristics

Sample size: planned number of clusters
300 city blocks
Sample size: planned number of observations
Please see the pre-analysis plan for details.
Sample size (or number of clusters) by treatment arms
Please see the pre-analysis plan for details.
Minimum detectable effect size for main outcomes (accounting for sample design and clustering)
Please see the pre-analysis plan for details.
Supporting Documents and Materials

Documents

Document Name
Survey with chiefs
Document Type
survey_instrument
Document Description
File
Survey with chiefs

MD5: f04147b667dc913b4045e9b7a93d8e72

SHA1: cc4fdc42bbf6a0de7995f95706903ecb24effc88

Uploaded At: April 27, 2022

Document Name
Survey with households
Document Type
survey_instrument
Document Description
File
Survey with households

MD5: 3aedd7e7eec9738a13ac9604fc5e97d1

SHA1: 9e28cbe2fc9fa11f7d67e69fc08fa1db935ab182

Uploaded At: April 27, 2022

IRB

Institutional Review Boards (IRBs)

IRB Name
The Scientific Council of Nova School of Business and Economics
IRB Approval Date
2021-02-24
IRB Approval Number
N/A
IRB Name
The Scientific Council of Nova School of Business and Economics
IRB Approval Date
2022-01-04
IRB Approval Number
N/A
Analysis Plan

Analysis Plan Documents

Pre-Analysis Plan

MD5: 0a68cf3ded51dba3082a61974e1431f3

SHA1: 9ad7dc66aed295d21896f3195432eaf548684034

Uploaded At: April 27, 2022

Post-Trial

Post Trial Information

Study Withdrawal

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Intervention

Is the intervention completed?
Yes
Intervention Completion Date
November 24, 2021, 12:00 +00:00
Data Collection Complete
Yes
Data Collection Completion Date
June 30, 2022, 12:00 +00:00
Final Sample Size: Number of Clusters (Unit of Randomization)
Was attrition correlated with treatment status?
Final Sample Size: Total Number of Observations
Final Sample Size (or Number of Clusters) by Treatment Arms
Data Publication

Data Publication

Is public data available?
No

Program Files

Program Files
Reports, Papers & Other Materials

Relevant Paper(s)

Reports & Other Materials