In October 2013 a new study was released in the PLOS Medicine journal estimating the number of deaths following the 2003 invasion of Iraq. It attempted to avoid and make up for some of the criticism of previous surveys that looked at fatalities in the country. These included the 2004 and 2006 Lancet papers, the 2004 Iraq Living Conditions Survey, the 2007 Opinion Business Research (ORB) poll, and the 2008 Iraq Family Health Survey. The new report estimated 460,000 excess deaths occurred after the fall of Saddam Hussein. It didn’t give a figure for all violent deaths, but did say that for adults aged 15-60 132,000 died because of violence from 2003-2011, which is very similar to Iraq Body Count and figures recorded by the U.S. military. The Iraqi Family Health Survey and the Iraq Living Conditions were both within the range of the new one as well, while the two Lancet reports and the ORB questionnaire were far outside of it. While no survey can be authoritative the new PLOS one at least confirms that a few of the earlier estimates were capturing some of the death and destruction released by the Iraq War, while largely repudiating the Lancet articles.
The PLOS paper set out to avoid some of the criticism laid at previous Iraq death surveys on Iraq, and wanted a new up to date estimate since the last one was done in 2007. The new report questioned 2,000 randomly selected households in 100 clusters across the country. It used a random selection process to generate which clusters were to be surveyed. It then picked one house as the starting point, and then interviewed that one plus 19 adjacent ones. It wanted to use double the number of clusters as the 2004 and 2006 Lancet studies and a more sophisticated random selection process to reduce the chance of missing high and low conflict related death areas. This was due to one critique leveled at the two Lancet articles called the “main street bias.” That argued that pollsters went to main streets and then polled the cross streets, which had the highest chance of violence occurring, and thus led to high death estimates. The Lancet papers were questioned about how exactly they went about deciding what areas were to be surveyed as well.
To prepare for the survey the team met in Kurdistan in March 2011 to go over procedures, then trained the survey teams, which were made up of Iraqi medical doctors with experience in polling. The groups set out across the country from May to July, and then everyone reconvened in September to go over the preliminary findings. Households were questioned about all the births and deaths they experienced since 2001. When a passing was reported a death certificate was requested. Those were produced 74% of the time, and a certificate was reported but not seen 17% of the time. For war related fatalities specific causes and who was responsible were asked for. Adults were then queried about their siblings’ experiences. That resulted in data for another 24,759 people. A supervisor then went to one randomly selected household in each cluster to repeat the survey as a quality check. In the end there was a 98.55% response rate among the 2,000 households. Training and supervision are important facets to conducting a scientific survey. The fact that violence had decreased considerably by 2011 when the poll was conducted also meant that there was access to almost every part of the country. Only five out of the 2,000 households for example could not be questioned because of threatening or hostile behavior. Raising questions about siblings also greatly increased the available data that could be analyzed.
Another part of the study was an attempt to account for Iraq’s displaced and refugee population. The group consulted secondary sources to estimate how many refugees there were. A number of calculations were then made with that figure to come up with a number of deaths amongst refugees. The authors knew that they missed many possible excess deaths amongst this group, which was one shortcoming they acknowledged in their findings. At the same time a large number of Iraqis have returned to their homes or have settled in new parts of the country since violence subsided in 2008, so the poll might have captured more of this group then they believed.
To come up with their findings they broke up their data by time periods. They estimated a crude death rate by counting the number of deaths in all households in each time period, and then divided that by the number of persons and years they lived within those eras. The baseline crude death rate was set for the period before the war from 2001 to March 2003. To calculate the war time deaths they used the differences between the crude death rate for each time period and the crude death rate for the pre-war era. For the siblings data they knew there were biases and tried to adjust for that. Another issue was that households might not have been able to remember everything accurately since they had to recall events from several years ago.
The final results found almost half a million deaths since 2003. The pre-war crude death rate from 2001 to 2003 was 2.89 per 1,000. The wartime rate was 4.55 per 1,000 from March 1 2003 to June 30, 2011. By multiplying those rates by the estimated population they came up with approximately 405,000 excess deaths with a range of 48,000 to 751,000 after 2003. Another 55,000 fatalities were estimated for the refugees for a total of 460,000 deaths in the post-invasion period. A total number for violent deaths was not given, but a rate for adults aged 15-60 was estimated at 132,000 during the war. Overall, the author’s believed that 60% of the excess deaths were a direct result of the war. The other 40% came from the collapse of infrastructure and services that occurred after the invasion. Like previous surveys a major problem with calculating crude death rates was that Iraq lacks up to date census data. That means those figures could go up and down depending upon how many people tne report believed the country had.
The survey found a range of causes for the deaths. Amongst violent ones gunshots not bombs was the most common at 63%, followed by car bombs, 12%, other explosions, 9%, other war injuries, 9%, and airstrikes, 7%. Those most responsible were Coalition Forces, 35%, militias and insurgents, 32%, others/unknown, 21%, criminals, 11%, and Iraqi forces, 1%. For nonviolent deaths cardiovascular conditions were at 47%, then infant or childhood deaths/injuries, 12%, and chronic illness and non-war injuries were both at 11%. The prevalence of shootings showed how bloody the civil war period was. The deadliest period for Iraqis was from 2005-2007 when Baghdad and its environs were the center of the fighting. There, militias and insurgents were fighting for control of communities block by block. Bombings might have grabbed the headlines, but the sectarian war was at the street level involving assault rifles, pistols, and machine guns. That was also shown in the fact that the militias and insurgents were responsible for almost as many deaths as the Coalition, which fought pitched battles such as the two for Fallujah, the three against the Mahdi Army, as well as various other major campaigns. The non-violent deaths were blamed on the war as well by the authors. They wrote that the collapse of infrastructure and essential services like electricity and clean water were a result of the invasion and its aftermath.
There have been five previous surveys in Iraq trying to estimate the number of deaths since 2003. Only two dealt with violent casualties, while the other three looked at all possible fatalities. The reports found wide differences in mortality rates, and all came in for some sort of criticism such as potential bias in sampling, wide ranges of uncertainty intervals, small sample sizes, disputes over statistical methods, choice of population figures, incomplete questioning, and plausibility of results. The new PLOS Medicine paper did a comparison of crude death rates per 1,000 with some of the previous reports. The 2004 and 2006 Lancet polls were in the upper range of the PLOS pre-war rates, and far above it for the wartime period. The 2004 Lancet had a pre-war mortality rate of 5.0 per 1,000 from 2002-2003 and 12.3 per 1,000 from 2003-2004, while the 2006 one recorded 5.5 per 1,000 from 2002-2003 going up to 13.3 from 2003-2006. That compared to the PLOS’s 2.89 per 1,000 from 2001-2003 and 4.5 per 1,000 from 2003-2011. Another outlier was the 2007 Opinion Research Business poll that estimated a violent death rate of 10.3 per 1,000 in 15 of 18 provinces from 2003-2006. The Iraq Living Conditions Survey and the Iraq Family Health Survey on the other hand were both within the range of the new survey’s pre and post invasion rates. The Iraq Family Health Survey for instance reported 5.31 deaths per 1,000 from 2003-2006. Those similarities and differences were even starker when comparing estimated death counts. The 2004 Iraq Living Conditions survey estimated 24,000 deaths from 2003-2004. The first Lancet covered the same time period, and was four times higher at 98,000 killed from 2003-2004. That did not include Anbar, so the authors believed the total figure was much larger. The Iraq Family Health Survey released in 2008 calculated 151,000 deaths from 2003-2006. The second Lancet paper was for the same years and was more than four times that at 654,965. Even farther apart from all the rest was the Opinion Reach Business survey that estimated 1,033,000 deaths from 2003-2007. The PLOS report calculated figures for eight years, and found 460,000 fatalities. Its authors came up with three hypotheses for why their numbers were different than the others. Those were sampling differences, recall bias, and non-sampling errors. PLOS used different sampling methods from the two Lancet and Iraqi Family Health surveys. The Iraq Family Health Survey also skipped 115 of its clusters for security reasons and consulted Iraq Body Count to calculate how any deaths might have occurred in those areas. Finally, households were asked to recall events about themselves going back ten years, but also for their siblings in the newest poll, which probably led to underreporting of deaths as some were missed. The PLOS team also believed they missed many deaths from the refugee and displaced populations. Although the new report compared itself to the five previous ones, it seemed like it was going out of its way to avoid many of the criticisms laid at the Lancet articles. Although still widely accepted, the Lancet estimates for deaths have faced intense criticism by academics. Many thought the 2004 and 2006 papers came up with far too high estimates. The new survey is just one more piece of evidence that those two polls were off the mark. In comparison, the Iraq Living Conditions and Iraq Family Health Survey appear to be more on point.
Comparison Of Pre-Iraq War Crude Death Rates
PLOS Medicine 2.89 per 1,000 2001-2003
2004 Lancet 5.0 per 1,000 2002-2003
2006 Lancet 5.5 per 1,000 2002-2003
Comparison Of Post-Invasion Crude Death Rates
PLOS Medicine 4.5 per 1,000 2003-2011
Iraq Family Health Survey 5.31 per 1,000 2003-2006
Opinion Research Business 10.3 per 1,000 2003-2006
2004 Lancet 12.3 per 1,000 2003-2004
2006 Lancet 13.3 per 1,000 2003-2006
Comparison Of Estimated Deaths
Iraq Living Conditions 24,000 2003-2004
2004 Lancet 98,000 2003-2004
Iraq Family Health Survey 151,000 2003-2006
2006 Lancet 654,965 2003-2006
Opinion Research Business 1,033,000 2003-2007
PLOS Medicine 460,000 2003-2011
The new survey has received a large amount of press as well as received critiques and gained supporters. John Tirman who commissioned the Lancet study wrote that people that criticized that report were doing a disservice by trying to play down the number of people killed by the Iraq War. He pointed to the PLOS paper as more evidence of the high cost of the U.S. invasion. Tom Paulson in Humanosphere claimed that the new survey verified the 2006 Lancet paper. Those two ignored the fact that both the Lancet crude death rate estimates were outside the range of the new survey, and that 460,000 killed over eight years is not close to the second Lancet’s 654,000 over just three. Josh Dougherty an analyst for Iraq Body Count and University of London Economics Professor Michael Spagat both pointed that out. Dougherty noted that the PLOS survey only found 76 violent deaths from 2003-2006 compared to 300 by the 2006 Lancet. He also estimated that if the new report was limited to just the 2nd Lancet period it would come up with less than 200,000 deaths, more than three times lower. Spagat critiqued the wide confidence interval in the new survey of 48,000-751,000 stating that probably made their estimated 460,000 killed too high rather than too low as the authors have repeatedly said to the media. Joshua Keating in Slate and John Rentoul in the Independent each argued that the PLOS report is roughly congruent to Iraq Body Count and the U.S. military’s figures released by Wikileaks of 100,000-126,000 killed. Finally Dr. Prabhat Jha of the Center for Global Health Research in Toronto was quoted in the Los Angeles Times pointing out that the lack of an accurate census for Iraq could mean that the estimated number of deaths could be lower if the population was higher than the 32 million used in the survey’s calculations. With one of the fastest growing populaces in the Middle East and North Africa there’s a good chance of that. Overall, those that have used the PLOS paper to support Lancet have not read the new report. It is more of a refutation of the 2004 and 2006 Lancets than a confirmation. There’s a chance that the estimated deaths from the new report are actually lower, which would make it even farther away from the two Lancets.
The PLOS Medicine article adds another important piece to the argument over how many Iraqis died after the 2003 invasion. First, it is another paper that shows that the two Lancet reports were far too high in their estimates for deaths following the fall of Saddam Hussein. That was previously shown with the Iraq Living Conditions, the Iraq Family Health Survey, and various academic criticisms. Second, it shows that Iraq Body Count’s method of recording deaths using media reports while not perfect does a very good job as its estimate for violent deaths is very close to the PLOS one for adults. Finally, it highlights just how deadly the sectarian war was in Iraq. Today bombings by Al Qaeda in Iraq are causing the majority of fatalities in the country’s deteriorating security situation. If shootings were to suddenly increase that would be a good sign that a civil war is breaking out again as insurgents, militias, and the security forces battle for control. In a war, especially like the one in Iraq where the government broke down for a few years a definitive number for fatalities will never be determined. It’s only through various surveys and studies that a rough estimate can be made. The PLOS report adds to this very important debate on the human cost of the Iraq invasion.
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