'Hablemos entre Patas': A Randomized-Controlled Trial of a WhatsApp Intervention to Reduce Intimate Partner Violence

Last registered on November 29, 2022


Trial Information

General Information

'Hablemos entre Patas': A Randomized-Controlled Trial of a WhatsApp Intervention to Reduce Intimate Partner Violence
Initial registration date
October 17, 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
October 25, 2022, 9:49 AM EDT

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

Last updated
November 29, 2022, 4:30 PM EST

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



Primary Investigator

Duke University

Other Primary Investigator(s)

PI Affiliation
Harvard University
PI Affiliation
Duke University
PI Affiliation
Inter-American Development Bank
PI Affiliation

Additional Trial Information

On going
Start date
End date
Secondary IDs
Prior work
This trial does not extend or rely on any prior RCTs.
Intimate partner violence (IPV) prevention programming worldwide has traditionally centered on providing victim assistance, greater awareness of legal rights, and changing social norms, relying solely on women’s participation and action, while men have largely been excluded from prevention efforts.

'Hablemos entre Patas' (HEP) is a men-focused IPV prevention intervention delivered by trained male hosts to a group of 50 men via WhatsApp, an instant messaging application. Over 30 days, each host facilitates discussion on masculine norms and shares daily behavioral and skill-building challenges to improve relationship dynamics, reduce violence, and change men’s attitudes towards violence against women.

HEP is designed to impact the following outcomes: 1) men's understanding of consensual sex and communication with female partners about sex; 2) men's emotional regulation and communication skills to control violent behaviors, communicate and resolve conflict; and 3) men's knowledge and skills to communicate on finances and shared household management and reduced conflict over finances. Through discrete (virtual) interactions in groups with other men, HEP offers men a community of like-minded men who are also seeking to improve their relationships. The group offers space and social support for men to challenge each other to change attitudes, confront patriarchal norms, and ultimately change their behavior.

The main analyses of the experiment take place at the couple level; therefore, only partnered men are eligible to participate. We will conduct phone surveys (baseline and endline) to men participants and their female partners. IPV and other IPV-related outcomes will be measure from female partners' reponses.
External Link(s)

Registration Citation

Boyer, Christopher et al. 2022. "'Hablemos entre Patas': A Randomized-Controlled Trial of a WhatsApp Intervention to Reduce Intimate Partner Violence." AEA RCT Registry. November 29. https://doi.org/10.1257/rct.10043-1.1
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Experimental Details


HEP is a digital challenge-based program designed by the International Rescue Committee (IRC) that is delivered by a male host to groups
of 50 Peruvian men through WhatsApp. Over a 30-day period, the host shares daily behavioral and skill-building challenges on relationships
and household management intended to improve relationship dynamics and reduce violence. In the group chat, the host provides specific behaviors men can practice with their partners to achieve their relationship and identity goals. These behaviors focus on improving communication,
emotional regulation, shared household responsibilities and sexual consent.

RMC promotes gender-equitable, violence-free relationships by directly linking men to guidance on shared household management, sex-positive
communication skills, joint financial planning, and emotional regulation skills to manage anger impulses. RMC’s methods incorporate human-centered design, field-wide “best practices”, and research on effective behavior change across a range of outputs.
Intervention Start Date
Intervention End Date

Primary Outcomes

Primary Outcomes (end points)
Main Analysis focuses on:

1. Intimate Partner Violence
2. Control and Decision Making
3. Sexual Consent
4. Communication at home
5. Conflict Resolution
Primary Outcomes (explanation)

Secondary Outcomes

Secondary Outcomes (end points)
Secondary Outcomes (explanation)

Experimental Design

Experimental Design
This study measures the effects of the RMC program through a (staggered) randomized control trial.

There are two survey waves. A baseline survey is conducted before randomization and an endline survey approximately 6 months after the intervention. Data from men and women are collected via phone surveys.

There are three sources of recruitment: (i) Social media advertising (SM), (ii) government referrals (GOV), and (iii) random digit dialing (RDD).

Individuals from SM register using an online form and then are invited by phone to participate in the study. The team also received a database of potential participants from the Peruvian Ministry of Women. Participants were also contacted and were invited to participate in the study. Finally, the third group of participants was contacted by phone following a random digit dialing approach and were also invited to receive the program.

Experimental Design Details
Randomization Method
Randomization is done within recruitment batches. As men are recruited, we form batches of 500 couples with complete baseline surveys. 250 men are assigned to receive the RMC program and 250 to the control group. Randomization is conducted within strata defined by level of physical intimate partner violence in the last 6 months as reported by the female partner at baseline. The 250 participants in the treatment group are then randomized into 5 groups of 50 to form a WhatsApp group chat and receive the program.

We repeat this algorithm 5 times forming 5 batches as recruitment progress.
Randomization Unit
Randomization is at the couple level.
Main analyses are conducted at that level, with additional analysis conducted at the individual level.
Was the treatment clustered?

Experiment Characteristics

Sample size: planned number of clusters
2,500 couples
Sample size: planned number of observations
5,000 individuals
Sample size (or number of clusters) by treatment arms
1,250 couples RMC program, 1,250 control.
Minimum detectable effect size for main outcomes (accounting for sample design and clustering)

Institutional Review Boards (IRBs)

IRB Name
Innovations for Poverty Action IRB
IRB Approval Date
IRB Approval Number
Analysis Plan

Analysis Plan Documents


MD5: 5f2b0fa3fdc6704009b857b8ec860418

SHA1: 4e75447ebc0304ac09e5f4da90842199d81f7d13

Uploaded At: October 17, 2022


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