Not sure how to delete this

Last registered on January 23, 2023


Trial Information

General Information

Not sure how to delete this
Initial registration date
November 23, 2022

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
January 23, 2023, 7:58 AM EST

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



Primary Investigator

Universitat de Barcelona

Other Primary Investigator(s)

Additional Trial Information

In development
Start date
End date
Secondary IDs
Prior work
This trial does not extend or rely on any prior RCTs.
Personal relationships have a great effect in many aspects in our life; particularly, during our school years, friendship is a key factor for many individuals. On the other hand, performance during these years, specially the years just previous to entering the university.
We want to identify how the relationship with different classmates can affect performance when working in group, and how best pair these students to improve their knowledge process. We will also study gender differences when setting these groups and differences in their performance.
Finally, we will look at other aspects related both with relationships and performance, such as the effect of bullying or generosity towards your peers.
External Link(s)

Registration Citation

Izquierdo Nofuentes, Àlex. 2023. "Not sure how to delete this." AEA RCT Registry. January 23.
Experimental Details


We make students work in pairs assigned randomly and compare it with their results working individually and taking into account who they are working with.
Intervention Start Date
Intervention End Date

Primary Outcomes

Primary Outcomes (end points)
Performance, relationships, bullying, dictator game.
Primary Outcomes (explanation)

Secondary Outcomes

Secondary Outcomes (end points)
Secondary Outcomes (explanation)

Experimental Design

Experimental Design
We conduct a series of surveys and tests at different students in schools and high schools.
Experimental Design Details
We ask students to classify their peers according to their level of friendship and willingness to work with. Afterwards they solve an individual test, a test in groups and a final individual test. The test in groups is in pairs chosen randomly. Teachers are also asked about which pairs they will form in class and why.
We then compare the group performance and transfer knowledge of several treatments, such as working with your best friend, working with the same partner the teacher would have chosen for you, etc.
Randomization Method
Public lottery, computer
Randomization Unit
Was the treatment clustered?

Experiment Characteristics

Sample size: planned number of clusters
20 schools
Sample size: planned number of observations
1200 pupils
Sample size (or number of clusters) by treatment arms
20 schools
Minimum detectable effect size for main outcomes (accounting for sample design and clustering)

Institutional Review Boards (IRBs)

IRB Name
Comissió de Bioètica de la Universitat de Barcelona
IRB Approval Date
IRB Approval Number


Post Trial Information

Study Withdrawal

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Is the intervention completed?
Data Collection Complete
Data Publication

Data Publication

Is public data available?

Program Files

Program Files
Reports, Papers & Other Materials

Relevant Paper(s)

Reports & Other Materials