Researchers began to use rigorous experiments more than 20 years ago to test policies that would improve the lives and well-being of the poorest people in the world. This movement grew and now randomized controlled trials (RCTs), which were once only available for medical interventions, are part of the mainstream research community studying global development.
People around the globe have benefitted from the knowledge gained through RCTs of every kind. It has helped to develop better drugs and other health interventions as well as education opportunities, improved agricultural technologies, and programs to distribute cash that are much needed. These benefits have not always flowed equally or been available to those most in need.
Nature this week reports on the pernicious and widespread effects of inequality in all forms. This special collection includes articles that examine the ways that COVID-19 has contributed to inequality, factors that contribute to gender inequalities in science, and analysis of interventions to reduce poverty.
Researchers are trying to find the root causes and the symptoms of social inequalities. They are also facing their own roles in complex socio-economic systems in which many benefits, such as wealth, often flow to those already enjoying these advantages.
Researchers can ensure that their research is not contributing to social injustices. Unfortunately, public-health research often results in uneven distribution of the benefits. The benefits of health interventions, including COVID-19 vaccines and drugs, can improve overall public safety. However, if they reach rich people or people who have high-quality care before the less fortunate, it will lead to inequality.
Even though the interventions are intended to alleviate poverty, they may not have that effect. Numerous studies have shown that cash transfer RCTs are most beneficial to the most economically disadvantaged and poorest people. Economists are concerned that not all RCTs will benefit the poorest. Their concern stems from the fact that not enough data is available to allow researchers to accurately assess whether poverty reduction efforts are being made. An RCT may show that an educational program helps children stay in school longer. However, that does not mean that poverty (and inequality!) are being reduced. We don't know if scientists report on socio-economic statuses of participants before and after trials.
Researchers are looking at ways to improve RCT design to account for equity, inclusion and diversity from the beginning. Researchers must ensure that they capture relevant factors like ethnicity, culture, and socio-economic background.
Real life is complicated. It is hard to run large enough trials to make statistically valid observations about sub-populations. Scientists must include people from under-served and poor populations as equal partners in their studies. This includes taking their views into consideration from the design phase. Researchers should also report data in a way that allows them to be aggregated in systematic literature reviews.
Modern society has extreme wealth and severe poverty. This is morally unacceptable. As one of the United Nations Sustainable Development Goals, 2015 saw world leaders commit to ending poverty in all forms by 2030. The world had made steady progress, though too slow, on this front before the COVID-19 epidemic. The pandemic changed the trend and drove millions of people back into poverty. The World Bank estimates that 657 million people, or 8% of the world's population, live on less than US$1.90 a day. This is 36 million more than the projections of where we would be in 2020 if there hadn't been the pandemic, and 76 millions more than those for 2022.
The world needs new technologies and policies that reduce poverty and inequality while also protecting the environment. Social scientists and economists need all the tools they can use to assist policymakers in solving these great challenges. This will include RCTs, but trials must be fair in order to succeed.