– One afternoon last month, a young woman with a tablet computer sat next to Alphonsine Umurerwa on the living room couch, asking questions, listening carefully.

She learned that the woman’s 23-year-old daughter, Sandrine Umwungeri, had been very sick for about a year, gradually becoming so weak she stopped leaving their tin-roofed home. The family thought she had malaria.

Medicines didn’t help. In March, she died.

The interviewer asked: When did Sandrine begin to feel weak? Did she have a fever? Did her skin take on a yellow hue? Each typed answer determined the next question to pose.

This was a “verbal autopsy,” an interview in which a trained health worker asks a close relative or caretaker about a recently deceased person. Increasingly, health officials are using these tools and their computer algorithms to learn more about the global course of human disease.

About 50 countries have attempted such projects, and the list is growing. Bloomberg Philanthropies — a major funder of international health data initiatives — recently announced it will devote $120 million over the next four years to continue projects in 20 previously funded countries, and add five more.

That includes money for verbal autopsies, as well as cancer registries and other programs to gather accurate data.

“With more and better data on causes of death, more countries can save more lives,” said Michael Bloomberg, the philanthropy’s founder. The work is badly needed, experts say.

An estimated 60 million people in the world will die this year, and half will have no death certificates or other records describing what killed them. That means the common understanding of overall disease and mortality trends in the developing world often relies upon estimates and guesswork. So do the decisions many countries make about which health problems to prioritize.

“The scale of the problem is really quite staggering,” said Lucia D’Ambruoso, a University of Aberdeen researcher. “There’s a moral imperative, as well as analytical one, to be able to shine a light on those otherwise invisible deaths.”

To be sure, knowing what’s killing people can be tricky even in developed countries. For example, though the United States requires doctors to sign death certificates, recent studies suggest some doctors put down certain conditions as a default, which is one reason why some experts believe heart disease has been overreported as a cause of death in the U.S.

But it’s far more problematic to collect accurate data in countries where only a fraction of deaths occur in hospitals, or with doctors present. In Rwanda, an estimated 20% of deaths occur in hospitals, and there is just one licensed doctor for every 8,000 people, said data from the Rwanda Medical and Dental Council.

The verbal autopsy campaign was pioneered more than 50 years ago, in small physician-led research projects.

Clearly, verbal autopsies have drawbacks. They rely on grief-stricken people to recall details and the results may vary on what questions are asked and how responses are interpreted.

Some health advocates — including philanthropists Bill and Melinda Gates — have pushed for other methods like minimally invasive tissue sampling. But that requires trained technicians, and samples have to be taken and shipped within 24 hours of death.

About 2,700 verbal autopsies have been done in nine small pockets of Rwanda. At first, neighbors perceived the questions as intrusive. But over time, most people have come to accept them.

“When we explain to them why we do this, in the end they will understand and answer our questions,” said Janvier Ngabonziza, who conducts the interviews in a rural area called Rwamagana.

The verbal autopsy of Sandrine Umwungeri was conducted by Leonie Mfitumukiza, who paused often to offer comfort and consolation. Afterward, she said she believes Umwungeri died of diabetes, not malaria. But she noted that she was gathering information, not drawing any conclusion.