They actually are on the ground and do hospital and morgue counts. From Iraq Body Count the coalition forces were responsible for approximately 350 deaths in 2005, 550 deaths in 2006, and some 700 deaths in 2007. The remaining deaths of some 80K are from the insurgency and al-Qaeda.
Problem is that (recently it changed I think) the Ministry of Health in Iraq, was since the elections under the rule of the Sadrists. Their stated goal is the withdrawal of all coalition troops. There is reason to be very wary of the informations coming from the Iraqi Health ministry 2004-2007.