... Violent deaths were mainly attributed to coalition forces - and most individuals reportedly killed were women and children.
Dr Les Roberts, who led the study, said: "Making conservative assumptions we think that about 100,000 excess deaths, or more, have happened since the 2003 invasion of Iraq.
"Violence accounted for most of the excess deaths and air strikes from coalition forces accounted for most of the violent deaths."
He said his team's work proved it was possible to compile data on public health "even during periods of extreme violence".
The sample included randomly selected households in Baghdad, Basra, Arbil, Najaf and Karbala, as well as Falluja.
Lancet editor Richard Horton said: "With the admitted benefit of hindsight and from a purely public health perspective, it is clear that whatever planning did take place was grievously in error."
He went on: "Democratic imperialism has led to more deaths not fewer. This political and military failure continues to cause scores of casualties among non-combatants."
He urges the coalition forces to rethink their strategy to "prevent further unnecessary human casualties".
"For the sake of a country in crisis and for a people under daily threat of violence, the evidence we publish today must change heads as well as pierce hearts," he said.
I wouldn't bet on piercing hearts. I suspect many soldiers already have pain in their hearts at the civilian deaths, but for most Americans it's an annoying astraction.
100,000. That's a city. It's much more than all the people I know. If the average victim weighed 60 lbs, than's 6 million pounds of person.
If the average victim was 12 years old, that's at least 5,000,000 lost years of life. Five million years ago we didn't even have Homo Erectus.
By the standards of the Iran-Iraq war, Rwanda, and the Congo, of course, it's a small number. It may yet be dwarfed by the deaths of a future Iraqi civil war.
By the standards of a civilized society ...
There are times when I would say war is unavoidable. (I might be wrong.) If it must be done, then do it with maximum care and the least harm possible. Treat children, at the least, as we would treat our own children.
We did not have the forces to invade Iraq "responsibly". We did not have the support of the world needed to find a way to get out of Iraq quickly. Rumsfeld was either delusional about the consequences of his choices, or he made an evil choice for evil ends. Bush did not fire Rumsfeld, evidently he approved.
If this were a just world they would be tried for crimes against humanity. Any educated adult, capable of reading and thinking, who votes for Bush November 2nd is also indicating they approve as well.