Abstract
Vitamin A deficiency (VAD) is a widespread health problem among young children and pregnant women in the developing world. This problem is most serious in Sub-Saharan Africa, where according to the World Health Organization, 26% of preschool children are estimated to be deficient. One effective and low cost solution to fight VAD is to introduce a biofortified staple food crop that is rich in vitamin A, such as the beta-carotene-rich orange fleshed sweet potato (OFSP). Although, sweet potato is one of the major staple food crops for many African countries, its production is dominated by white, yellow or cream colored sweet potato varieties that have very low vitamin A content. Clearly, greater effort is needed to scale up the adoption of OFSP and achieve the potential nutritional benefits of this technology. Scaling Up Sweet Potato Through Agriculture and Nutrition (SUSTAIN) is a project led by the International Potato Center (CIP) with support from the U.K. Department for International Development designed to achieve precisely this goal. It builds on recent advances in the biofortification of sweet potato and proof-of-concept research to deliver the benefits of OFSP to millions of farming households and thousands of urban and rural consumers in Kenya, Malawi, Mozambique, and Rwanda.
Achieving “impact at scale” is at the heart of the SUSTAIN project. Concomitant to the goal of achieving ‘impact at scale,’ is the SUSTAIN project’s desire to deliver the production and nutrition benefits to millions of people effectively and efficiently. This randomized controlled trial (RCT) is designed to provide an objective and independent evaluation of the effectiveness and cost-effectiveness of the SUSTAIN project’s scaling up approach so as to support and facilitate the innovation process within the project, and to learn from it for future expansion. The RCT focuses on one SUSTAIN country -- Rwanda, where the project has set a goal of reaching 60,000 direct beneficiaries and 250,000 indirect beneficiaries by taking an integrated agriculture-nutrition-marketing approach. This integrated approach consists of implementing following components/strategies of promoting OFSP production, sale, and consumption in eight target districts across the Northern, Southern and Eastern Provinces in Rwanda:
1. Agriculture: The agriculture component includes two sub-components—vine distribution and agronomic training. The project plans to distribute vines of improved OFSP varieties to households with children less than 5 years old or with pregnant women. About 100 vines each of two selected improved varieties will be distributed free of cost to eligible households, followed by a second round of vine dissemination in the third season to the same households, but at a subsidized cost which will be a fraction of the normal cost. These beneficiary households will be targeted through farmer organizations or farmer field schools (FFS). Under the agronomic training sub-component, all the members (men or women) of the farmer organization or the farmer field school that will be targeted by the project for vine distribution will receive agronomic training on growing OFSP at the time of vine distribution and during the growing season.
2. Nutrition: This component encompasses two strategic elements or sub-components—messaging and counseling. All the members of the farmer organization or the farmer field school (men and women), and pregnant women and lactating mothers who visit the local health facilities will receive nutritional ‘messages’ on the importance of OFSP as a source of vitamin A, which is essential for good health, and how OFSP as part of a balanced diet contributes to vitamin A intake. The nutrition ‘counseling’ sub-component will include incorporating the promotion of OFSP consumption in the on-going nutrition education curriculum of the community health worker and health center. In this counseling component, the emphasis will be on 'doing', 'demonstrating' and 'showing' rather than simply telling/informing about OFSP. All the women and caregivers in the village with children less than 5 years and pregnant women will be targeted for the counseling sub-component of the nutrition intervention. The SUSTAIN project will link the nutrition component with the planned and ongoing health and nutrition activities implemented by the Rwanda Ministry of Health through the health centers and community health workers (CHWs).
3. Marketing: The marketing interventions will include two sub-components—training and market linkage. All the members of the farmer groups and FFS that received vines will also receive in-depth (but context specific) training (delivered several times during the project phase) on how to process OFSP, market it, meet the demand for roots quality, and organize finances. Under the market linkage sub-component, the SUSTAIN project will actively promote the linkage between OSFP growers and processors and other actors in the value chain. This sub-component will focus on a proactive action by the project to find processors willing to work with farmers and then equipping the farmers with knowledge, tools and skills to ensure they meet the processors’ requirements in terms of roots quality and delivery schedules. CIP / SUSTAIN project implementers will work with groups/cooperatives and FFS in this component, but marketing is expected to take place at the household level.
This evaluation study in Rwanda uses a randomized-controlled trial (RCT) field experiment to test the effectiveness of different combinations of this integrated agriculture-nutrition-market approach of promoting the adoption and consumption of OFSP at scale. The research design consists of randomly assigning project villages to one of the following six treatment arms:
1. Base model: All the components of the integrated Agriculture, Nutrition and Marketing approach
2. Base model less nutrition counseling
3. Base model less marketing
4. Base model less nutrition counseling and marketing
5. Base model, but only one season
6. Base model with the second time vine distribution at a higher price
These treatment arms are designed to include or exclude project components and sub-components that substantially differ in projected cost and benefits. Costs include both financial resources and human/institutional capacity to reach the target number of beneficiaries. Given SUSTAIN’s resource constraints, the goal is to maximize the number of beneficiaries (direct + indirect) per unit of cost. The benefits of the project are measured on two dimensions – a) by the total number of beneficiaries reached/impacted (i.e., the extensity dimension); and b) the average effect per beneficiary as measured by the adoption and consumption of OFSP by children, women and men three years after the project intervention (i.e., the intensity and sustainability dimension).
This RCT is designed to address the following research questions:
1. Which combinations of market promotion and nutrition information dissemination are most cost effective for promoting production and consumption of OFSP by a large number of beneficiaries (scale) to meet their nutritional needs (intensity) over time (sustainability)?
2. Which factors are important in determining OFSP adoption by farmers, and their consumption among children and women? Do the different promotion strategies influence them differently?
3. How do the effects of various project components involving training and knowledge dissemination (e.g., nutritional information, market information) differ across different recipient and household characteristics (e.g., gender, age, education of recipient of training and of household head)?
The plan is to collect baseline and end-line data from a sample of project beneficiaries across all six treatment arms. In order to capture potential spillover effects (e.g., farmer to farmer sharing of vines and adoption of OFSP by households who were not directly targeted by the project), researchers will also collect some basic information for all households in selected treatment villages for this RCT in listing (or census) exercises both at baseline and end-line. This beneficiary level data in combination with cost tracking data to be collected by the project monitoring and evaluation team will be the bases for addressing the research questions identified for this evaluation.
The survey data will contribute to conducting a rigorous evaluation of SUSTAIN project interventions across a range of outcome indicators. These indicators include: adoption of OFSP, consumption of OFSP by children less than 5 and women of child bearing age (especially, pregnant and lactating women), frequency of foods rich in vitamin A, dietary diversity and history, infant and young child feeding practices, sweet potato production and productivity, market penetration, cost-effectiveness of scaling-up mechanisms and not least, gender outcomes and impacts. By measuring these indicators before and after project intervention, we will be able to assess how effective SUSTAIN strategies are in: improving the consumption of foods rich in vitamin A by children under age 5 and women of child bearing age; improving dietary diversity; encouraging planting of OFSP; encouraging consumption of OFSP; increasing incomes of farmers who sell OFSP in markets; and increasing agricultural production.