Growing Together: A cluster randomised evaluation of digital agroecology advice and collective action for vegetable value chain transformation in Vietnam"

Last registered on August 10, 2026

Pre-Trial

General Information

Title

RCT ID

AEARCTR-0019299

Initial registration date

August 05, 2026

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

August 10, 2026, 3:07 PM EDT

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

Locations

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Primary Investigator

Name

Christian Grovermann

Affiliation

FiBL

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Other Primary Investigator(s)

PI Name

Hoi Pham Van

PI Affiliation

VNUA

Contact Investigator

PI Name

Dzung Dong Dao

PI Affiliation

Hanoi School of Business

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Additional Trial Information

Status

On going

Start date

2026-05-01

End date

2028-06-30

Keywords

Agriculture, Behavior, Environment & Energy, Labor, Welfare

Additional Keywords

Value Chain Development

JEL code(s)

Secondary IDs

Prior work

This trial does not extend or rely on any prior RCTs.

Abstract

This clustered randomised control trial tests the effectiveness of production system and value chain development for safe and agroecologically produced vegetables in the peri-urban zone of Hanoi, Vietnam. The intervention is planned to be rolled out between November 2026 and August 2027 and and will be carried out jointly by extension specialists from Vietnam National University of Agriculture (VNUA) and experts from selected retailers in close collaboration with 46 lead farmers from 23 villages, who will receive in-depth coaching. Contents will be shared by the lead farmers in each intervention village through a demo plot as well as videos and posters with practical advice on agroecological practices, cooperative organisation, and marketing opportunities. The impact will be evaluated jointly by researchers from VNUA and FiBL under the Vietnam-Swiss funded Agroeconfirm project. The primary outcomes for evaluation are the adoption of agroecological practices (e.g. legume and straw mulching, reduced tillage, biochar application) and farmers' attitudes towards cooperative membership and certification. Secondary outcomes include agroecology performance measured though FAO's Tool for Agroecology Performance Evaluation (TAPE), labour inputs, and marketing channels. The trial is powered to detect adoption effects of at least 10 percentage points for the selected practices, which have current adoption levels below 15%. Baseline data was collected in June 2026 and endline data will be collected in December 2027 from 46 villages (15-16 farmers per village). The study area includes Ha Noi, Hung Yen and Ninh Binh provinces. We sampled from a list of villages with at least 50 farm households that practice all-year vegetable production.

External Link(s)

Registration Citation

Citation

Dong Dao, Dzung, Christian Grovermann and Hoi Pham Van. 2026. "Growing Together: A cluster randomised evaluation of digital agroecology advice and collective action for vegetable value chain transformation in Vietnam"." AEA RCT Registry. August 10. https://doi.org/10.1257/rct.19299-1.0

Sponsors & Partners

Experimental Details

Interventions

Intervention(s)

The intervention is planned to be rolled out between November 2026 and August 2027 and and will be carried out jointly by extension specialists from Vietnam National University of Agriculture (VNUA) and experts from selected retailers in close collaboration with 46 lead farmers from 23 villages, who will receive in-depth coaching. Contents will be shared by the lead farmers in each intervention village through a demo plot as well as videos and posters with practical advice on agroecological practices, cooperative organisation, and marketing opportunities. The practices include legume and straw mulching, reduced tillage and biochar application. Potential buyers from shops for safe and organic vegetables will engage for information on value chain partnerships between retailers and farmers, including details on cooperative formation, post-harvest vegetable storage and transport, traceability requirements and market channels.

Intervention Start Date

2026-11-01

Intervention End Date

2027-08-31

Primary Outcomes

Primary Outcomes (end points)

Adoption of agroecological practices (e.g. legume and straw mulching, reduced tillage, biochar application) and farmers' attitudes towards cooperative membership and certification.

Primary Outcomes (explanation)

Secondary Outcomes

Secondary Outcomes (end points)

Agroecology performance measured though FAO's Tool for Agroecology Performance Evaluation (TAPE), labour inputs, and marketing channels.

Secondary Outcomes (explanation)

Information on TAPE: https://www.fao.org/agroecology/database/en/

Experimental Design

The experiment is carried out in the peri-urban zone of Hanoi, Vietnam covering three provinces. It is clustered at the village level, with 23 villages randomly assigned to the control group and 23 villages randomly assigned to the treatment group. The focus on villages with a sufficient amount of producers who engage in year-round vegetable production led to a concentration of eligible villages in some parts of the study area. Therefore, we implemented a 1000m distance rule in our randomisation. Balance checks confirmed appropriate balance among 27 selected variables at baseline.

Experimental Design Details

Not available

Randomization Method

Randomisation was performed using Stata software, including a 1000m distance rule between villages

Randomization Unit

Village-level randomisation

Was the treatment clustered?

Yes

Experiment Characteristics

Sample size: planned number of clusters

23 villages with each village having at least 50 farmers practising year-round vegetable production

Sample size: planned number of observations

724 farmers representing 724 farms with year-round vegetable production (15-17 farms per village)

Sample size (or number of clusters) by treatment arms

23 villages in the treatment group and 23 villages in the control group

Minimum detectable effect size for main outcomes (accounting for sample design and clustering)

The minimum detectable effect size is a 10 percentage point increase in adoption for the agroecological practices that serve as primary outcome variables

Supporting Documents and Materials

IRB

Institutional Review Boards (IRBs)

IRB Name

FiBL Ethics Committee

IRB Approval Date

2026-04-15

IRB Approval Number

FSS-2026-005

Analysis Plan