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Pricing Experiment - Intervention to fight anemia and improve well-being in a very low income setting
Last registered on May 15, 2013


Trial Information
General Information
Pricing Experiment - Intervention to fight anemia and improve well-being in a very low income setting
Initial registration date
Not yet registered
Last updated
May 15, 2013 12:06 PM EDT
Primary Investigator
CESS Nuffield - FLAME University
Other Primary Investigator(s)
PI Affiliation
PI Affiliation
Additional Trial Information
Start date
End date
Secondary IDs
Iron deficiency anemia (IDA) has been linked to low productivity in adults, slowing of cognitive and physical growth among children and, in the elderly, increased risk of cognitive impairment and physical disability, as well as decreased muscle strength.

Distributing iron supplements appears to be an impractical policy in resource-poor settings where the public health systems do not have the capacity to maintain a large-scale distribution system. Iron supplementation of foods is therefore an attractive alternative: it requires no additional effort on the part of the consumer, and can be done relatively cheaply in centralized locations. While NIN's Iron (and Iodine) Fortified Salt (DFS) has been studied extensively by the National Institute of Nutrition (Hyderabad) and others for safety and efficacy in humans, willingness to pay for this new technology has not been established.

In this experiment, we randomly assign discounts for Double (iron and iodine) Fortified Salt at the household level in order to estimate demand at various prices among low-income rural households in India (Bihar). We also assign three types of information campaign delivery at the village level to understand their relative effects on take-up.
External Link(s)
Registration Citation
Banerjee, Abhijit, Sharon Barnhardt and Esther Duflo. 2013. "Pricing Experiment - Intervention to fight anemia and improve well-being in a very low income setting." AEA RCT Registry. May 15. https://doi.org/10.1257/rct.11-1.0.
Experimental Details
We made Double Fortified Salt available for sale in 43 villages by approaching local stores to sell it. We created 11 types of vouchers with showing prices net of discount, which varied in privates stores and/or government shops (the Public Distribution System). These vouchers were randomly assigned to households that could use them to purchase DFS at a discount during a 4-week period.

Each village was randomly assigned to one of three types of communications delivery which informed people about the role of Double Fortified Salt in preventing anemia:
- posters and other written promotional materials hung at shops
- the above plus a street play conducted by actors
- all of the above plus a household visit from a government health worker
Intervention Start Date
Intervention End Date
Primary Outcomes
Primary Outcomes (end points)
Purchase of DFS by the household, Product knowledge
Primary Outcomes (explanation)
Product knowledge was measured with a short set of questions about DFS and anemia designed to find out if the respondent had ever heard of them (separately) and what was known about each one (separately).
Secondary Outcomes
Secondary Outcomes (end points)
Secondary Outcomes (explanation)
Experimental Design
Experimental Design
We proceed in this order:
1. Random selection of 43 villages from one block within Bhojpur District.
2. Random selection of 99 households from District Rural Development Authority census lists.
3. Random assignment of 9 households per village to each voucher type.
4. Random assignment of 14 or 15 villages to each information campaign type.
5. Salt stocking and information campaign delivery.
6. Baseline survey on demographics, anemia knowledge, DFS knowledge. Voucher delivery.
7. After 4 weeks, redeemed voucher collection from stores.
8. Endline household survey on knowledge of DFS, anemia, use of voucher, experience with product.
Experimental Design Details
Randomization Method
Computer generated randomization in office outside study area.
Randomization Unit
Villages and households
Was the treatment clustered?
Experiment Characteristics
Sample size: planned number of clusters
43 villages
Sample size: planned number of observations
4257 households
Sample size (or number of clusters) by treatment arms
14 or 15 villages in each info campaign. 387 households per voucher type.
Minimum detectable effect size for main outcomes (accounting for sample design and clustering)
Supporting Documents and Materials

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Request Information
IRB Name
IFMR (Chennai)
IRB Approval Date
IRB Approval Number
IRB00007107; FWA00014616; IORG0005894
IRB Name
IRB Approval Date
IRB Approval Number
Post Trial Information
Study Withdrawal
Is the intervention completed?
Is data collection complete?
Data Publication
Data Publication
Is public data available?
Program Files
Program Files
Reports, Papers & Other Materials
Relevant Paper(s)