Displaced people and communities who have fled conflict depend heavily on external aid to meet their basic needs, but too little empirical evidence exists on the effectiveness of humanitarian assistance. To date, most humanitarian assistance has been provided in kind, but there has been a trend in the past 10 to 20 years towards the use of cash-based modalities such as vouchers, e-transfers, and direct cash transfers. In partnership with the United Nations in the Democratic Republic of Congo (DRC), researchers evaluated the impact of vouchers for essential household items on the health and well-being of recently displaced individuals and their host communities. The program improved the mental health of participants in the shorter- and longer-run, but did not affect children’s physical health, household resilience, or social cohesion.

Policy Issue 

Conflict and disasters worldwide leave millions of people in urgent need of life-saving assistance such as shelter, food, water, and healthcare. In 2018 alone, 206 million people needed humanitarian aid, and governments and private institutions donated US$ 29 billion to humanitarian response. This amount represents a growth of almost a third since 2014;1 however, contributions are still insufficient to meet current needs. With pressing needs and limited resources, implementing effective interventions becomes critical. To date, most humanitarian assistance has been provided in kind, but there has been a trend in the past 10 to 20 years towards the use of cash-based modalities such as vouchers, e-transfers, and direct cash transfers. Some studies have examined their impact on a limited number of outcomes, especially food security, economic, and livelihood recovery. However, difficulties in collecting information in fragile environments, and ethical concerns about conducting research in these environments, make evidence on the subject limited.

Context of the Evaluation 

The Democratic Republic of the Congo (DRC) has experienced a long period of violence that encompasses the First and Second Congolese Wars (1996-1997 and 1998-2003). Despite the formal end to the Second Congolese War in July 2003, sporadic waves of violence have continued. As of December 2019, more than five and a half million Congolese people have been internally displaced due to armed conflict and natural disasters.2

In response to the large-scale displacement, the United Nations Children's Fund (UNICEF) and the United Nations Office for the Coordination of Humanitarian Affairs (OCHA) operate the Rapid Response to Movements of Population program (RRMP). This program assists populations made vulnerable by displacement, disease, and natural disasters in eastern DRC, in part through the provision of cash-based assistance to the displaced and their host communities.

Details of the Intervention 

Researchers conducted a randomized evaluation to measure the impact of a voucher program on children’s physical health, adults’ mental health, social cohesion, and resilience. Additionally, the researchers assessed whether the receipt of humanitarian assistance influenced the decision to migrate.

The program was implemented between 2017 and 2018 and provided vouchers for essential household items (EHIs) to internally displaced people (IDPs) across 25 villages in the North Kivu province. The vouchers were redeemable at an NGO-organized fair for EHIs. Researchers identified the households in each village who were the most vulnerable, among those not vulnerable enough to qualify for RRMP’s assistance, and randomly assigned half to receive vouchers. All households that would receive assistance from RRMP continued to receive assistance; the evaluation resulted in additional beneficiary households. In total, 976 households were enrolled in the study.

The research team collected data at three points in time: shortly before the voucher fair, about six weeks after the fair, and about one year after the fair.3  In addition to survey-based measures, local nurses measured children’s weight, height, and mid-upper arm circumference (to assess malnutrition) and conducted tests for malaria and anemia.

Results and Policy Lessons 

The intervention had a positive significant effect on the participants’ mental health. Before receiving assistance, 33 percent of respondents had an anxiety or depression disorder. Six weeks after, people that received the voucher had a 0.32 standard deviation units (SDU) higher (better) mental health index. This effect persisted for the long term, as the index remained 0.19 SDU higher after one year. There were no effects on the child's health, social cohesion, or resilience indices.4

Considering the low cost and the positive effects on mental health, these findings suggest that asset transfer programs could be attractive to policymakers and humanitarian organizations working with populations that have been forcibly displaced and are living with host communities. Results also prove randomized evaluations can be used to investigate the impact of interventions in humanitarian settings where challenges related to logistics, fragility, security, and ethics often loom large.


1 Development Initiatives, “Global Humanitarian Assistance Report.”  

2 Internal Displacement Monitoring Centre (IDMC), “Country Information: Democratic Republic of the Congo.”

3 This last round of data collection was funded by IPA’s Peace and Recovery program. The earlier rounds were funded by the International Initiative for Impact Evaluation (3ie).

4  Quattrochi et al 2020a; Quattrochi et al 2020b.

Development Initiatives. “Global Humanitarian Assistance Report,” 2019. http://devinit.org/wp-content/uploads/2019/09/GHA-report-2019.pdf.

Internal Displacement Monitoring Centre (IDMC). "Country Information: Democratic Republic of the Congo." IDMC, 2019. https://www.internal-displacement.org/countries/democratic-republic-of-the-congo

John Quattrochi, Ghislain Bisimwa, Tyler Thompson, Peter van der Windt, and Maarten Voors. 2020a. “Assessing the Effects of Humanitarian Assistance on Internally Displaced Households: Experimental Evidence from a Voucher Program in the Congo.” 3ie Impact Evaluation Report, 107. https://www.3ieimpact.org/sites/default/files/2020-03/IE107-TW6.1043-Humanitarian-DRC.pdf

John Quattrochi, Ghislain Bisimwa, Peter van der Windt, and Maarten Voors. 2020b. “Effect of an Economic Transfer Program on Mental Health of Displaced Persons and Host Populations in Democratic Republic of Congo: A Randomised Controlled Trial” SSRN Working Paper: https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3706054

John Quattrochi, Jenny Aker, Peter van der Windt, and Maarten Voors. 2020c. “Contributions of experimental approaches to development and poverty alleviation: Field experiments and humanitarian assistance. World Development, 127, 1-3.