Farmer soils information for decision making
Last registered on February 18, 2020

Pre-Trial

Trial Information
General Information
Title
Farmer soils information for decision making
RCT ID
AEARCTR-0005470
Initial registration date
February 18, 2020
Last updated
February 18, 2020 2:22 PM EST
Location(s)
Primary Investigator
Affiliation
McGill University
Other Primary Investigator(s)
PI Affiliation
University of Florida
PI Affiliation
Columbia University
PI Affiliation
University of Illinois at Urbana-Champaign
Additional Trial Information
Status
Completed
Start date
2014-08-01
End date
2019-09-30
Secondary IDs
Abstract
Low fertilizer use in sub-Saharan Africa contributes to low crop yields and poverty. Extension services advise the use of fertilizers but may not recommend fertilizer types that address prevailing soil deficiencies, potentially resulting in the perception that fertilizer is not profitable. This randomized control trial tests how fertilizer recommendations based on farm-level soil tests interact with the ability to finance fertilizer to influence fertilizer application and crop yields.
External Link(s)
Registration Citation
Citation
Harou, Aurelie et al. 2020. "Farmer soils information for decision making." AEA RCT Registry. February 18. https://doi.org/10.1257/rct.5470-1.0.
Experimental Details
Interventions
Intervention(s)
Intervention Start Date
2015-12-01
Intervention End Date
2016-02-29
Primary Outcomes
Primary Outcomes (end points)
Fertilizer use (kg/acre) (farmer reported), fertilizer purchases (kg) (agro-input dealer reported), and maize yields (kg/acre) (farmer reported).
Primary Outcomes (explanation)
Secondary Outcomes
Secondary Outcomes (end points)
Secondary Outcomes (explanation)
Experimental Design
Experimental Design
We test how fertilizer recommendations based on farm-level soil tests interact with the ability to finance fertilizer to influence fertilizer application and crop yields. We randomly select 50 villages in Morogoro Rural and we assign 20 randomly chosen villages to the treatment group and 30 to the control group. In each of the 20 treatment villages, we randomly select 40 farmers to participate in the study, and we assign 10 farmers randomly selected from these 40 to each of the three treatment arms and to the control group. In each of the 30 control villages, we randomly select 10 farmers. The treatment group includes 600 farmers in 20 treatment villages. The control group includes 500 farmers: 200 control farmers in treatment villages and 300 farmers in control villages. The treatments include 3 arms: plot-specific recommendations, an agricultural input voucher, plot-specific recommendations and an agricultural input voucher.
Experimental Design Details
Randomization Method
Randomization done in office by a random number generator on computer.
Randomization Unit
Farming household
Was the treatment clustered?
Yes
Experiment Characteristics
Sample size: planned number of clusters
50 villages
Sample size: planned number of observations
1,100 farming households
Sample size (or number of clusters) by treatment arms
Recommendation treatment: 20 villages, 200 farmers
Voucher treatment: 20 villages, 200 farmers
Recommendation and voucher treatment: 20 villages, 200 farmers
Control: 50 villages, 500 farmers
Minimum detectable effect size for main outcomes (accounting for sample design and clustering)
IRB
INSTITUTIONAL REVIEW BOARDS (IRBs)
IRB Name
IRB Approval Date
IRB Approval Number
Post-Trial
Post Trial Information
Study Withdrawal
Intervention
Is the intervention completed?
No
Is data collection complete?
Data Publication
Data Publication
Is public data available?
No
Program Files
Program Files
Reports and Papers
Preliminary Reports
Relevant Papers