Field
Trial Status
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Before
in_development
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After
on_going
|
Field
Trial End Date
|
Before
November 07, 2022
|
After
January 06, 2023
|
Field
Last Published
|
Before
November 04, 2022 05:40 PM
|
After
November 07, 2022 10:18 PM
|
Field
Intervention End Date
|
Before
November 07, 2022
|
After
November 08, 2022
|
Field
Randomization Method
|
Before
Randomization done by Qualtrics. We use a block randomization method which is achieved by the randomizer function embedded in Qualtrics. Among the 1,200 participants recruited, 600 will be randomly assigned to the control group, and the other 600 will be randomly assigned to the treatment group.
|
After
Randomization done by Qualtrics. We use a block randomization method which is achieved by the randomizer function embedded in Qualtrics. Among the 1,600 participants recruited, 800 will be randomly assigned to the control group, and the other 800 will be randomly assigned to the treatment group.
|
Field
Planned Number of Observations
|
Before
1,200 US citizens who are over 18 years old
|
After
1,800 US citizens who are over 18 years old
|
Field
Sample size (or number of clusters) by treatment arms
|
Before
600 participants in the control, 600 participants in the treatment group.
|
After
800 participants in the control, 800 participants in the treatment group.
|
Field
Power calculation: Minimum Detectable Effect Size for Main Outcomes
|
Before
According to our previous experiment data (the experiment was pre-registered on AEA RCT registry, doi: https://doi.org/10.1257/rct.7070), to observe a change of 20% standard deviation (sd = 26), power of 0.8, and alpha of 0.05 (two-sided), we need a minimum detectable effect size of around 400. Assuming a 70% retention rate in our two-stage study, we need the minimum detectable effect size to be 571.
|
After
According to our previous experiment data (the experiment was pre-registered on AEA RCT registry, doi: https://doi.org/10.1257/rct.7070), to observe a change of 20% standard deviation (sd = 26), power of 0.8, and alpha of 0.05 (two-sided), we need a minimum detectable effect size of around 400. Assuming a 50% compliance rate of encouragement in our two-stage study, we need the minimum detectable effect size to be 800 per group.
|
Field
Pi as first author
|
Before
No
|
After
Yes
|