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A pioneering study discovered that giving schoolchildren in poor countries a pill that costs as little as 50 cents and protects them from parasitic infections has dramatic effects. This research over 20 years reveals the benefits carry over into adulthood. NPR's Nurith Aizenman reports.
NURITH AIZENMAN, BYLINE: In the mid-1990s, economist Michael Kremer was visiting Kenya.
MICHAEL KREMER: I mean, I was on vacation. I wasn't there for a research trip or something.
AIZENMAN: A friend there mentioned he was starting an aid program to help elementary school kids, including by giving them deworming pills against all sorts of nasty intestinal parasites that can cause kids to miss school.
KREMER: I suggested that if he chose twice as many schools and then they initially started working in half of them and then later, you know, expanded, then they could measure the impact of what they were doing.
AIZENMAN: By comparing what happened to the kids who got the pills first versus those who got them in the expansion up to three years later, you could see if it made a difference. This kind of experiment is called a randomized controlled trial, and it's long been the way that scientists like, say, biologists determine whether a new medication works. But at the time, randomized controlled trials were just starting to gain ground as a tool for economists to check if programs to alleviate poverty worked.
KREMER: This was the first one I was involved in (laughter), and this changed the nature of my research a lot.
AIZENMAN: Not just Kremer's research - his Kenya experiment helped pave the way for an explosion in these kinds of randomized controlled trials. Last year, Kremer shared the Nobel Prize in Economics for pioneering this approach. The experiment also turned deworming into a very popular form of aid because the first set of results released in 2004 by Kremer and a collaborator, Edward Miguel of University of California, Berkeley, showed that giving the kids the pills reduced absenteeism and dropouts by 25%. Since then, Kremer and his collaborators have continued to follow thousands of kids in the original experiment as they grew up, entered the workforce.
KREMER: We have data 20 years out.
AIZENMAN: Now they've released those results. Giving out deworming pills to the kids at a cost of about 50 cents a year per kid has boosted their household income as adults by 13%.
KREMER: I thought that there'd be some impact, but I had no idea that there would be an impact of this magnitude. What this shows is that if people are given a chance to be healthy, to get education, then they can benefit from that.
AIZENMAN: Some caveats - the income boost was limited to the men. Also, a few years ago, a team from the London School of Hygiene and Tropical Medicine did a reanalysis of Kremer and his colleagues' original data, slicing and dicing it using different statistical approaches. Co-author Alexander Aiken says he's not convinced school attendance went up. His reanalysis of the data...
ALEXANDER AIKEN: ...Raised major question marks over many of the findings.
AIZENMAN: And because Aiken doesn't think the original research proves that the deworming caused kids to spend more time in school, he doesn't see how it could have led them to earn higher incomes so many years later.
AIKEN: I'm not sure I really believe it.
AIZENMAN: So should funders back deworming programs? A lot of them are saying yes. Deworming is so cheap, even if the potential benefits are much smaller than Kremer and his collaborators' research suggests, it's worth it.
Nurith Aizenman, NPR News.
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