London ? A cheap method to detect cervical cancer using vinegar, cotton gauze and a bright light could save millions of women in the developing world, experts reported today.

The study, published in The Lancet medical journal, found a simple visual screening test to look for the early signs of cervical cancer reduced the numbers of cases by a quarter.

Cervical cancer is largely preventable. It causes about 250,000 deaths every year and is the second-most common cancer in women. Nearly 80 percent of those women are in the developing world.

The visual screening test is done by a nurse or trained health care worker who washes a woman’s cervix with vinegar and gauze using a speculum to hold it open. After one minute, any pre-cancerous lesions turn very white and can be seen with the naked eye under a halogen lamp.