By Gwynne Dyer, Contributor

The final indignity, if you are an Iraqi who was shot for accidentally turning into the path of a U.S. military convoy (they thought you might be a terrorist), or blown apart by a car bomb or an air strike, or tortured and murdered by kidnappers, or just for being a Sunni or a Shia, is that President George W. Bush and Prime Minister Tony Blair will deny that your death happened. The script they are working from says (in Mr. Bush's words last December) that only "30,000, more or less" have been killed in Iraq during and since the invasion in March, 2003.

So they have a huge incentive to discredit the report in the British medical journal The Lancet last week that an extra 655,000 Iraqis have died since the invasion in excess of the natural death rate: 2.5 per cent of the population. "I don't consider it a credible report," said Mr. Bush, without giving any reason why he didn't. "It is a fairly small sample they have taken and they have extrapolated it across the country," said a spokesman of the British Foreign Office, as if that were an invalid methodology. But it's not.

Before the invasion

The study, led by Dr. Les Roberts and a team of epidemiologists from the Bloomberg School of Public Health at Johns Hopkins University in Baltimore, was based on a survey of 1,849 households, containing 12,801 people, at 47 different locations chosen at random in Iraq. Teams of four Iraqi doctors - two men and two women - went from house to house and asked the residents if anybody had died in their family since January, 2002 (fifteen months before the invasion).

The most striking thing in the study, in terms of credibility, is that the pre-war death rate in Iraq for the period January 2002-March 2003, as calculated from their evidence, was 5.5 per thousand per year. That is virtually identical to the U.S. government estimate of the death rate in Iraq for the same period. Then, from the same evidence, they calculate that the death rate since the invasion has been 13.3 per thousand per year. The difference between the pre-war and post-war death rates over a period of forty months is 655,000 deaths.

The study, which was largely financed by the Massachusetts Institute of Technology's Center for International Studies, has been reviewed by four independent experts. One of them, Paul Bolton of Boston University, called the methodology "excellent" and said it was standard procedure in a wide range of studies he has worked on: "You can't be sure of the exact number, but you can be quite sure that you are in the right ballpark."

The numbers are real

This is not a political smear job. Johns Hopkins University, Boston University and MIT are not fly-by-night institutions, and people who work there have academic reputations to protect. The Lancet,founded 182 years ago, is one of the oldest and most respected medical journals in the world. These numbers are real.

The most disturbing thing is the breakdown of the causes of death.

Over half the deaths - 56 per cent - are due to gunshot wounds, but 13 per cent are due to air strikes. No terrorists do air strikes. No Iraqi government forces do air strikes, either, because they don't have combat aircraft. Air strikes are done by 'coalition forces' (i.e. American and British), and air strikes in Iraq have killed over 75,000 people since the invasion.

Gwynne Dyer is a London-based independent journalist whose articles are published in 45 countries.