WASHINGTON (Reuters) - New estimates of war deaths in 13 nations including Vietnam, Ethiopia and Bangladesh show that previous counts vastly understated the lives lost to war in the past half century, researchers said on Thursday.
The new estimates relied on data from nationally representative population surveys done by the U.N. World Health Organization in these countries earlier this decade to calculate death tolls in wars waged from 1955 to 2002.
In most of the countries, this method pointed to much higher loss of life than broadly cited media estimates of the various war death counts had shown, the researchers said.
For example, the method indicated 3.8 million Vietnamese died in the protracted fighting in Vietnam, mostly from 1955 to 1975, compared to previous estimates cited by the researchers of 2.1 million.
Christopher Murray of the University of Washington said the findings, published in the British Medical Journal, suggest standard ways of tracking war deaths using media, eyewitness and combatant accounts tend to underestimate deaths, particularly in smaller wars.
Murray, who heads the university's Institute for Health Metrics and Evaluation, and colleagues designed a method of figuring violent war-related deaths using data on siblings of respondents in large household surveys conducted later in peacetime.
Random samples of people in the 13 countries were asked about their brothers and sisters, including whether they had died of wartime injuries. The researchers then extrapolated the data to come up with national death toll estimates.
In Ethiopia, the method indicated there have been 579,000 wartime deaths, higher than the previous estimate cited in the study of 275,000. In Bangladesh, the toll was put at 269,000, up from the previous estimate of 58,000.
Country by country, on average, the old estimates were about three times lower than the new ones.
In the 13 countries combined, the new method figured there were 5.4 million deaths from 1955 to 2002, topping the previous combined estimates of 2.8 million, the researchers said.
In Bosnia, the researchers figured 176,000 war deaths, up from the 55,000 previous estimate. In Sri Lanka, the new estimate was 215,000 deaths, compared the previous estimate of 61,000.
In Zimbabwe, the new estimate was 141,000 war deaths, compared to the previous estimate they cited of 28,000.
Other countries examined in the study were Myanmar (Burma), Georgia, Guatemala, Laos, Namibia, the Philippines and the Democratic Republic of Congo.
The study did not look at war dead in Iraq or Afghanistan.
Ziad Obermeyer of Brigham and Women's Hospital and Massachusetts General Hospital in Boston, another of the researchers, said accurate estimates of death tolls during wartime are extremely difficult to make.
He also said the findings undercut the idea that the advent of modern weapons like "smart bombs" had made war less lethal.
(Editing by Todd Eastham)