Randomized controlled trials provide rigorous tests of the effectiveness of social interventions.

• Credit and Larger Version

September 26, 2022

Countless lives have been helped or saved with the scientific evidence provided by an experimental approach three economists unleashed more than 20 years ago. Their innovation gave rise to a scientific movement that is clearly illuminating causality — how one thing directly causes another — within the intricate chaos of human behavior and society.

What are the most efficient ways to change the world for the better? What actions will effectively reduce poverty and illness, minimize violent crime or strengthen community resilience to extreme weather? Many governments and philanthropic organizations in the U.S. and abroad grapple with those tough questions when deciding how best to use the limited resources entrusted to them by taxpayers or donors.

Answering such complex questions requires clearly seeing something that is all too often hidden or murky: causality. Did a particular policy or initiative actually cause the desired effect? Or was it just a coincidence?

In the 1990s, a small group of researchers developed a scientifically rigorous way to design complex social experiments that can clearly distinguish those all-important causes from mere correlations and coincidences. Their method recast a statistical technique traditionally used in clinical medical trials, giving rise to a new movement in social science research and winning them a Nobel Prize.

Continue reading in Science Matters.

The U.S. National Science Foundation propels the nation forward by advancing fundamental research in all fields of science and engineering. NSF supports research and people by providing facilities, instruments and funding to support their ingenuity and sustain the U.S. as a global leader in research and innovation. With a fiscal year 2023 budget of $9.5 billion, NSF funds reach all 50 states through grants to nearly 2,000 colleges, universities and institutions. Each year, NSF receives more than 40,000 competitive proposals and makes about 11,000 new awards. Those awards include support for cooperative research with industry, Arctic and Antarctic research and operations, and U.S. participation in international scientific efforts.

 Get News Updates by Email 

Connect with us online
NSF website: nsf.gov
NSF News: nsf.gov/news
For News Media: nsf.gov/news/newsroom
Statistics: nsf.gov/statistics/
Awards database: nsf.gov/awardsearch/

Follow us on social
Twitter: twitter.com/NSF
Facebook: facebook.com/US.NSF
Instagram: instagram.com/nsfgov