Latest blogs

New evidence on humanitarian aid: Cash transfers improve outcomes for Venezuelan migrants in Colombia

A recently-completed impact evaluation conducted by 3ie in the context of the Venezuelan crisis contributes to filling this void. Our study shows that a multipurpose cash transfer program for Venezuelan migrants in Colombia yielded positive effects on migrants' incomes, food security, savings, and labor force participation rates.

Insights from the Development Evidence Portal: Where is the evidence (like, on a map)?

As we mark 3ie’s 15 years, it’s an opportune time to take stock of the “state of the evidence”, using one of our major contributions to the field of evidence use: the Development Evidence Portal (DEP). The Portal makes evidence about the effectiveness of development interventions accessible to a large constituency of evidence users, funders, and decision-makers across the globe.

Wrapping up USAID's Evidence Month: Panelists discuss pathways to build an evidence culture

As we've discussed on this blog before, the development community has made tremendous strides in producing and using rigorous evidence, and it also still has a long way to go to build a strong evidence culture. The closing plenary for USAID's Agency Learning and Evidence Month on 27 April reflected recent years' progress and the remaining challenges.

Effective interventions for putting child immunization back on track in L&MICs

Despite being highly effective in preventing avoidable disease and death among children, routine child immunization remains well below targets. Child immunization has been especially hit hard by the COVID-19 pandemic, reversing years of gains. In 2021, 25 million children missed essential vaccines, a high not seen since 2009. Putting immunization back on track, especially in low- and middle-income countries (L&MICs), is an urgent priority.

15 years of 3ie: Reflecting on our contributions and the work ahead

As a mission-driven non-profit international organization, this mission remains the north star that motivates our staff, board of directors, fellows, and partners. Occasionally it is important to pause, reflect on where we are, and celebrate what we have achieved as a community. What better occasion to do so than for our 15th anniversary!

Five lessons from our Transparent, Reproducible, and Ethical Evidence (TREE) reviews

We have been consolidating our efforts to develop stronger systems for producing transparent, reproducible, and ethical evidence (TREE). We have emphasized asking ourselves the right questions at the right times, even when there are no easy answers. We’ve examined very specific questions such as: Does a state of scarcity or equipoise make it ethical to withhold an intervention from a control group?

Martin Ravallion, poverty researcher and impact evaluation pioneer: 1952-2022

Martin, regularly ranked amongst the world’s leading development economists, played a central role in the mainstreaming of poverty in the development agenda. In these days of the SDGs, younger people may not be aware that there was a time when poverty was at best a marginal concern in most development discourse. Modernization and growth held sway.

3ie Living Evidence Gap Map: New food systems evaluations focus on the big picture

Food systems transformation is a global problem, and increasingly evaluations of food systems interventions are considering national and transnational solutions. The world's food system is under threat from the “three Cs” – COVID, climate, and conflict. As the Food and Agriculture Organization notes, the war in Ukraine brought these threats into sharp focus in 2022, pushing the already high global food prices even higher. To mitigate the effects of, and eventually recover from, these shocks, we need to know what interventions are effective at improving food security and nutrition, who they work for, and what they cost. In our newest update to our living Evidence Gap Map we've added 72 new studies, some of which show positive effects of nation-wide plans to shift land ownership policies.

One small step for Norway, one giant leap for evidence-informed decision-making in Norwegian aid

If economists are the ‘dismal scientists’ always harping on about limited resources, evaluators are often considered the ‘pessimist scientists’ who only see the half-empty glass, rather than the half-full one. The end of the year is, however, a perfect time to break with that tradition. It is a time to reflect and appreciate progress, promising initiatives, and flickers of hope. Evidence suggests that positive reinforcement can be effective in ensuring that positive developments or behaviors are maintained.

Best practices for working with survey partners and monitoring data quality

Collecting primary data for impact evaluations can be both costly and time-intensive, especially in terms of planning, designing survey instruments, setting up field protocols, training enumerators, data collection, supervision, quality assurance, and handling field-level challenges. Evaluators and researchers often partner with survey firms to implement and manage field operations for data collection.


Evidence Matters is 3ie’s blog. It primarily features contributions from staff and board members. Guest blogs are by invitation.

3ie publishes blogs in the form received from the authors. Any errors or omissions are the sole responsibility of the authors. Views expressed are their own and do not represent the opinions of 3ie, its board of commissioners or supporters.