In the October 2006 NY Times, we read:

BAGHDAD, Oct. 10 — A team of American and Iraqi public health researchers has estimated that 600,000 civilians have died in violence across Iraq since the 2003 American invasion, the highest estimate ever for the toll of the war here.

The figure breaks down to about 15,000 violent deaths a month, a number that is quadruple the one for July given by Iraqi government hospitals and the morgue in Baghdad and published last month in a United Nations report in Iraq. That month was the highest for Iraqi civilian deaths since the American invasion…

It is the second study by researchers from the Johns Hopkins Bloomberg School of Public Health. It uses samples of casualties from Iraqi households to extrapolate an overall figure of 601,027 Iraqis dead from violence between March 2003 and July 2006.

But today, the study is now in doubt:

A Johns Hopkins professor who co-authored a study suggesting that huge numbers of civilians have died during the U.S. war in Iraq was accused of ethics violations yesterday by a prominent group of polling researchers, and university officials announced that they are conducting their own review.

The rebuke, by the American Association for Public Opinion Research, came after an investigation into how Dr. Gilbert Burnham of the Bloomberg School of Public Health determined that nearly 655,000 Iraqis had died as a result of the U.S.-led invasion and its bloody aftermath. The results – which estimated hundreds of thousands more deaths than the Bush administration had reported – were published in 2006 in The Lancet, a leading British medical journal.

Officials of the association, of which Burnham is not a member, said Burnham refused to disclose the wording of his questions and basic methodological details of his research, a violation of the group’s code of ethics and practices. That makes it impossible for other researchers to verify the work, said Mary E. Losch, chairwoman of the AAPOR’s Standards Committee.

This isn’t good. Burnham’s actions have delivered a huge blow for the credibility of scientific research. And since the study involves a contentious issue like the Iraq War, he opens himself up to accusations of ideologically driven bias.