Its authors said that despite important gaps in data, the overall picture was clear: sex attacks on women are a big and widely overlooked problem.
Reporting in The Lancet, researchers carried out an overview of investigations in 56 countries.
Their data was trawled from scientific journals as well as "grey" literature, meaning reports in publications that may not be peer-reviewed, an acknowledged benchmark of research.
They identified 77 usable studies, providing 412 estimates of violence.
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"Our findings indicate a pressing health and human rights concern," the investigators said.
The highest rates were in sub-Saharan Africa -- 21 per cent in the centre (Democratic Republic of Congo) and 17.4 per cent in the south (Namibia, South Africa and Zimbabwe) -- followed by 16.4 per cent in Australia and New Zealand.
The lowest reported prevalence was in South Asia (India and Bangladesh) at 3.3 per cent and north Africa and the Middle East with 4.5 per cent.
"We found that sexual violence is a common experience for women worldwide and in some regions is endemic, reaching more than 15 per cent in four regions," said lead investigator Naeemah Abrahams of the South African Medical Research Council in Cape Town.
The true tally of sexual violence may be far higher in some regions, she said, pointing to South Asia in particular.
In an email exchange with AFP, Abrahams acknowledged the study's limitations.
Data were good from most of Europe, Oceania, Australasia, North America and Southeast Asia, but sketchy or lacking in parts of South Asia, north and central Africa and the Middle East. Some countries had no data at all.