Rosenkranz Prize winner uses statistics to assess rape-prevention efforts in Kenya

A Stanford Medicine statistician and his team are conducting a large, randomized trial to gather quantitative evidence about the effectiveness of a rape-prevention program in Africa.

- By Beth Duff-Brown

Rosenkranz Prize winner Mike Baiocchi and colleague Clea Sarnquist conduct research on the ground in Nairobi, Kenya, to determine whether a rape prevention program is truly making a difference.
Nichole Sobecki

In the slums of Nairobi, where sexual assault is as commonplace as it is taboo to discuss, a team of Kenyan counselors is teaching kids that no means no.

The girls learn to shout “Hands off my body!” and throw an elbow jab or a kick to the groin. The boys are encouraged to stand up for the girls and fight against the social traditions that have normalized rape. Through a series of role-playing exercises, the children also learn how to talk themselves out of precarious situations, use diversions and speak loudly when faced with potential attackers.

The behavioral intervention appears to be working. Observational studies have inferred that the incidence of rape has dropped dramatically — perhaps even by half.

But how do those who are devoted to protecting these girls from sexual violence prove to themselves and their donors that their efforts and dollars are making a difference?

This is where Mike Baiocchi comes in. His innovative approach to applying math to a real-world problem has earned him the 2017 Rosenkranz Prize for Health Care Research in Developing Countries.

Baiocchi, PhD, assistant professor of medicine at the Stanford Prevention Research Center, and his team are conducting a large, randomized trial to gather quantitative evidence about the effectiveness of the rape-prevention program No Means No Worldwide. Baiocchi plans to use the $100,000 prize to help fund the work.

Kenyan girls take a survey conducted by Baiocchi.
Nichole Sobecki

“That’s what I specialize in: messy, real-world data where you try to prove the cause-and-effect relationship,” he saids

Baiocchi and his team have designed a closed-cohort study that will track the behavior of about 5,000 girls and 1,000 boys in Kenya who are enrolled in No Means No Worldwide, which is training 300,000 girls and boys in Africa to prevent rape and teen pregnancy.

“The entire Rosenkranz selection committee was highly impressed both with the rigor of Mike’s work — which he publishes in top journals in the field of statistics — as well as his unconventional and potentially very impactful work on the prevention of gender-based violence in illegal settlements around Nairobi,” said Grant Miller, PhD, associate professor of medicine and a core faculty member at Stanford Health Policy.

Miller chairs the committee that selects the winners of the annual prize, which goes to promising young Stanford researchers who are investigating ways to improve health care and health policy in developing countries. The award’s namesake, George Rosenkranz, who holds a doctorate in chemistry, first synthesized cortisone in 1951, and later progestin, the active ingredient in birth control pills. He went on to establish the Mexican National Institute for Genomic Medicine. His family created the Rosenkranz Prize in 2009.

Overwhelming prevalence of sexual violence

The World Health Organization estimates that globally, one in three women experience sexual or physical violence. In Kenya, national surveys reveal that as many as 46 percent of Kenyan women experience sexual assault as children.

“In the roughest part of the Nairobi slums, 20 to 25 percent of high school girls will be raped this year,” said Baiocchi. “This program, however, looks like it is having the ability to cut that in about half. Our job is to tease out the evidence through careful measurement and design of experiment.”

To do this, Baiocchi and other members of the Stanford Gender-Based Violence Collaborative have traveled to Nairobi to collect baseline data. His partner on the project is Clea Sarnquist, DrPH, senior research scholar for the Global Child Health Program in the Department of Pediatrics.

An evaluation of the program, published in 2014 in Pediatrics, found that more than half of 2,000 high school girls who had completed the self-defense course had used their newfound skills to fend off sexual harassment or rape.

They’re play-acting and just being kids, but you are also watching them evolving and creating new ways to deal with these situations.

But Lee Paiva, the San Francisco-based founder of No Means No Worldwide, wanted more definitive proof. In a 2016 interview with Stanford Medicine magazine, she said that since establishing training in 2010 she often wondered about the true effectiveness of the program.

“A little voice inside me said, ‘What did you teach them?’” she said. “What did those kids actually get? What is that money really going to do?”

She determined that she wasn’t going to move forward on the program until she could answer those questions. That is when she turned to Stanford.

Baiocchi and Sarnquist spent several months last year working with their Kenyan partners, Ujamaa-Africa and the African Institute for Health and Development, in 90 schools in the poorest parts of Nairobi to establish the largest randomized trial of its kind.

They interviewed the girls who have taken part in the six-week empowerment and self-defense program taught by Kenyans who grew up in the same neighborhoods and are familiar with the local culture.

“It’s hard not to be extraordinarily excited when you watch these girls; they’re play-acting and just being kids, but you are also watching them evolving and creating new ways to deal with these situations,” said Baiocchi. The team is now tracking a fixed group of 5,000 girls and 1,000 boys, ages 10 to 16, over two years. This will give the researchers a better understanding of just how the girls are adopting the training and readapting to societal demands.

“Doing a randomized trial is slow, expensive and — if I’m being totally honest — anxiety-inducing because everything is laid so bare and you put things in motion today that won’t be resolved for another two years,” Baiocchi said. “But the reward is extraordinarily high-quality data that helps you understand what’s really going on. We need this level of evidence if we’re going to take on such a difficult problem.”

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2023 ISSUE 3

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