Vinegar test could prevent cervical cancer deaths worldwide each year, say researchers.
Wealthy countries have managed to reduce cervical cancer deaths by 80 percent thanks to the widespread use of regular Pap smears.
But cervical cancer remains the leading cause of cancer death among women in India and many other developing countries lacking the money, doctors, nurses or laboratories for widespread screening.
A primary health care worker swabs the woman's cervix with vinegar, which causes pre-cancerous tumors to turn white. The results are known a minute later when a bright light is used to visually inspect the cervix.
Aside from the cost savings, the instantaneous results are a major advantage for women in rural areas who might otherwise have to travel for hours to see a doctor.
The randomized study of 150,000 women over 15 years found that the vinegar test was able to reduce cervical cancer deaths by 31 percent.
The incidence of cervical cancer was essentially the same among the women who were screened every other year and those who were simply taught how to watch for warning signs.
Early detection is critical in successfully treating the disease.
"We hope our results will have a profound effect in reducing the burden of cervical cancer in India and around the world," said lead study author Surendra Srinivas Shastri, a professor of preventive oncology at Tata Memorial Hospital in Mumbai.
"This is the first trial to identify a cervical cancer screening strategy that reduces mortality and is feasible to implement on a broad scale throughout India and in other developing countries."
Health officials in the state of Maharashtra, where the study was conducted, are preparing to train primary health care workers to provide the vinegar screening to all women aged 35 to 64 in the state.
The researchers are also working with national health officials to make the screening available throughout the country.
The Indian government also plans to reach out to other low to moderate income countries to share the results and offer training resources.
If the program is fully implemented, it could prevent 22,000 cervical cancer deaths in India every year. That number would rise to 73,000 if it is implemented in resource-poor countries worldwide.
The use of primary health care workers -- who provide basic services in remote and rural areas where doctors and nurses are unavailable -- is a critical component of the strategy, Shastri said.
The workers who performed the screenings were local women with at least a 10th grade education and good communication skills who received four weeks of intensive training at the beginning and one-week refresher courses every year.
The study was released at the American Society of Clinical Oncology's annual meeting in Chicago.