thumb|right|White and red flags, representing Iraqi and American deaths, sit in the grass quad of [[The Valley Library on the Corvallis, Oregon campus of Oregon State University. As part of the travelling Iraq Body Count exhibit (not related to the Iraq Body Count project) the flags aim to "raise awareness of the human cost of the Iraq War." The exhibit uses The Lancet as its primary source.]]

The Lancet, one of the oldest scientific medical journals in the world, published two peer-reviewed studies on the effect of the 2003 invasion of Iraq and subsequent occupation on the Iraqi mortality rate. The first was published in 2004; the second (by many of the same authors) in 2006. The studies estimate the number of excess deaths caused by the occupation, both direct (combatants plus non-combatants) and indirect (due to increased lawlessness, degraded infrastructure, poor healthcare, etc.).

The first survey published on 29 October 2004, estimated 98,000 excess Iraqi deaths (with a range of 8,000 to 194,000, using a 95% confidence interval (CI)) from the 2003 invasion and subsequent occupation of Iraq to that time, or about 50% higher than the death rate prior to the invasion. The authors described this as a conservative estimate, because it excluded the extreme statistical outlier data from Fallujah. If the Fallujah cluster were included, the mortality estimate would increase to 150% over pre-invasion rates (95% CI: 1.6 to 4.2).

The second survey published on 11 October 2006, estimated 654,965 excess deaths related to the war, or 2.5% of the population, through the end of June 2006. The new study applied similar methods and involved surveys between 20 May and 10 July 2006. The Lancet surveys have been supported by some journalists, governments, epidemiologists and statisticians, and been met by criticism and disbelief from other journalists, governments, epidemiologists and statisticians. which not only met with widespread acceptance and no challenge when published in 2000, but resulted and was cited in a U.N. Security Council resolution that all foreign armies must leave Congo, a United Nations request for $140 million in aid, and the US State Department pledging an additional $10 million in aid. Similar studies have been accepted uncritically as estimates of wartime mortality in Darfur and Bosnia.

Roberts' regular technique is to estimate mortality by personal surveys of a sample of the households in the area under study; this method being chosen in order to avoid the under-counting inherent in using only reported deaths in areas so chaotic that many deaths are unreported, and to include those deaths not directly attributable to violence but nevertheless the result of the conflict through indirect means, such as contamination of water supply or unavailability of medical care. The baseline mortality rate calculated from the interviewees' reports for the period prior to the conflict is subtracted from that reported during the conflict, to estimate the excess mortality which may be attributed to the presence of the conflict, directly or indirectly. This technique has been accepted uncritically in the previous mortality surveys discussed above.

Because of the impracticality of carrying out an evenly distributed survey, particularly during a war, Roberts' surveys use "cluster sampling", dividing the area into a number of randomly selected, approximately equally populated regions; a random point is chosen within each region, and a fixed number of the households closest to that point are surveyed as a "cluster". While not as accurate as an evenly distributed survey of the same number of households, this technique is more accurate than merely surveying one household for each selected point.

In his study of Iraq, Roberts divided the country into 36 regions, attempting to sample 30 households for each cluster, and selecting 988 households, with 7868 residents. In September 2004, each surveyed household was interviewed about household composition, births, and deaths since January 2002. Of 78 households where members were asked to show documentation to confirm their claims after the interview was finished, 63 were able to present death certificates. According to the authors, 5 (0.5%) of the 988 households that were randomly chosen to be surveyed refused to be interviewed.

The relative risk of death due to the 2003 invasion and occupation was estimated by comparing mortality in the 17.8 months after the invasion with the 14.6 months preceding it. The authors stated, "Making conservative assumptions, we think that about 100,000 excess deaths, or more have happened since the 2003 invasion of Iraq." Among such "conservative assumptions" is the exclusion of data from Fallujah in many of its findings. Since interpreting the results of the study would be complicated by the inclusion of an outlier cluster in Fallujah, where heavy fighting caused far more casualties than elsewhere in Iraq, the study focused mainly on the results that excluded the Fallujah cluster. While the authors argued that the Fallujah cluster's inclusion could be justified as a normal part of the sampling strategy (the authors noted that other "hotspots" like Najaf had not ended up being surveyed), and the authors presented two sets of results in some cases (one set including the Fallujah data and one not), the article, and most press coverage of the article, stresses the data that excluded the Fallujah cluster.

The main debate in the media in the U.S. and UK focused on whether 98,000 (95% CI 8000–194,000) more Iraqis died as a result of coalition intervention, calculated from their estimate of an increased mortality of 1.5 times (95% CI 1.1–2.3) the prewar rate (excluding the Fallujah data). Had the Fallujah sample been included, the survey's estimate that mortality rates had increased about 2.5 times since the invasion (with a 95% CI 1.6–4.2) including the Fallujah data would have resulted in an excess of about 298,000 deaths (95% CI ?–?), with 200,000 concentrated in the 3% of Iraq around Fallujah (Roberts et al. p. 5).

According to the article, violence was responsible for most of the extra deaths whether or not the Fallujah data was excluded. Coalition airstrikes would be the main cause of these violent deaths if Fallujah data were included. The study concluded that: "Violent deaths were widespread, reported in 15 of 33 clusters, and were mainly attributed to coalition forces." and "Violence accounted for most of the excess deaths and air strikes from coalition forces accounted for most violent deaths."

The study estimates that the risk of death specifically from violence in Iraq during the period after the invasion was approximately 58 times higher than in the period before the war, with the CI95 being 8.1–419, meaning that there is a 97.5% chance that the risk of death from violence after the invasion is at least 8.1 times higher than it was before.

Newsday reported:

<blockquote>The most common causes of death before the invasion of Iraq were heart attacks, strokes and other chronic diseases. However, after the invasion, violence was recorded as the primary cause of death and was mainly attributed to coalition forces—with about 95 percent of those deaths caused by bombs or fire from helicopter gunships.</blockquote>

Criticisms and countercriticisms

Some criticisms have focused on the relatively broad 95% confidence intervals (CI95), resulting from the difficulty and scarcity of reliable sources.

Lila Guterman, after writing a long article in January 2005 in The Chronicle of Higher Education, wrote a short article in the Columbia Journalism Review that stated: "I called about ten biostatisticians and mortality experts. Not one of them took issue with the study's methods or its conclusions. If anything, the scientists told me, the authors had been cautious in their estimates. With a quick call to a statistician, reporters would have found that the probability forms a bell curve—the likelihood is very small that the number of deaths fell at either extreme of the range. It was very likely to fall near the middle."

A Ministerial Statement written 17 November 2004, by the UK government stated "the Government does not accept its [the study's] central conclusion", because they were apparently inconsistent with figures published by the Iraq Ministry of Health, based on figures collected by hospitals, which said that "between 5 April 2004 and 5 October 2004, 3,853 civilians were killed and 15,517 were injured".

Some critics have said that The Lancet study authors were unable to visit certain randomly selected sample areas. In an interview on the radio program "This American Life" however, the authors of the study say that they never substituted different, more accessible, areas, and that every place that was randomly selected at the beginning of the study was surveyed in full, despite the risk of death to the surveyors.

Critics of the Lancet study have pointed out other difficulties in obtaining accurate statistics in a war zone. The authors of the study readily acknowledge this point and note the problems in the paper; for example they state that "there can be a dramatic clustering of deaths in wars where many die from bombings". They also said that the data their projections were based on were of "limited precision" because the quality of the information depended on the accuracy of the household interviews used for the study.

The results of the study were politically sensitive, since a heavy death toll could raise questions regarding the humanitarian justifications on the eve of a contested US presidential election. Critics objected to the timing of the report, claiming it was hastily prepared and published despite what they perceived as its poor quality in order to sway the U.S. electorate. On this topic, Les Roberts stated "I emailed it in on Sept. 30 under the condition that it came out before the election. My motive in doing that was not to skew the election. My motive was that if this came out during the campaign, both candidates would be forced to pledge to protect civilian lives in Iraq. I was opposed to the war and I still think that the war was a bad idea, but I think that our science has transcended our perspectives."

  • 26 March 2005. Criticism by Stephen Apfelroth, Department of Pathology, Albert Einstein College of Medicine. Criticizes "several questionable sampling techniques that should have been more thoroughly examined before publication" and lists several flaws, including a "fatal" one, that "In such a situation, multiple random sample points are required within each geographic region, not one per 739,000 individuals."
  • 26 March 2005. Response by Les Roberts et al. to Apfelroth. Acknowledges flaws, but says "the key public-health findings of this study are robust despite this imprecision. These findings include: a higher death rate after the invasion; a 58-fold increase in death from violence, making it the main cause of death; and most violent deaths being caused by air-strikes from Coalition Forces. Whether the true death toll is 90,000 or 150,000, these three findings give ample guidance towards understanding what must happen to reduce civilian deaths.&nbsp;... Before publication, the article was critically reviewed by many leading authorities in statistics and public health and their suggestions were incorporated into the paper. The death toll estimated by our study is indeed imprecise, and those interested in international law and historical records should not be content with our study. We encourage Apfelroth and others to improve on our efforts. In the interim, we feel this study, as well as the only other published sample survey we know of on the subject, point to violence from the Coalition Forces as the main cause of death and remind us that the number of Iraqi deaths is certainly many times higher than reported by passive surveillance methods or in press accounts."

Other responses to criticism

The Chronicle of Higher Education also wrote an article discussing the differences in the survey's reception in the popular press over how it was received in the scientific community. "The government rejected this survey and its estimates as unreliable; in part absurdly because statistical extrapolation from samples was thought invalid. Imprecise they are, but to a known extent. These are unique estimates from a dispassionate survey conducted in the most dangerous of epidemiological conditions. Hence the estimates, as far as they can go, are unlikely to be biased, even allowing for the reinstatement of Falluja. To confuse imprecision with bias is unjustified."

Second study (2006)

A second study by some of the same authors was published in October 2006, in The Lancet.

<blockquote>We estimate that between March 18, 2003, and June, 2006, an additional 654,965 (392,979–942,636) Iraqis have died above what would have been expected on the basis of the pre-invasion crude mortality rate as a consequence of the coalition invasion. Of these deaths, we estimate that 601,027 (426,369–793,663) were due to violence.

An 11 October 2006 Washington Post article

Criticisms

The Iraq Body Count project (IBC), who compiles a database of reported civilian deaths, has criticised the Lancet's estimate of 601,000 violent deaths out of the Lancet estimate of 654,965 total excess deaths related to the war. An October 2006 article by IBC argues that the Lancet estimate is suspect "because of a very different conclusion reached by another random household survey, the Iraq Living Conditions Survey 2004 (ILCS), using a comparable method but a considerably better-distributed and much larger sample." IBC also enumerates several "shocking implications" that would be true if the Lancet report were accurate, e.g. "Half a million death certificates were received by families which were never officially recorded as having been issued" and claims that these "extreme and improbable implications" and "utter failure of local or external agencies to notice and respond to a decimation of the adult male population in key urban areas" are some of several reasons why they doubt the study's estimates. IBC states that these consequences would constitute "extreme notions". Later statements in a 2010 article by IBC say that the "hugely exaggerated death toll figures" from the 2006 Lancet report have "been comprehensively discredited" by recently published research.

Jon Pedersen of the Fafo Institute and research director for the ILCS survey, which estimated approximately 24,000 (95% CI 18,000–29,000) war-related deaths in Iraq up to April 2004, expressed reservations about the low pre-war mortality rate used in the Lancet study and about the ability of its authors to oversee the interviews properly as they were conducted throughout Iraq. Pedersen has been quoted saying he thinks the Lancet numbers are "high, and probably way too high. I would accept something in the vicinity of 100,000 but 600,000 is too much." However, another interviewer a week later painted a more measured picture of her criticisms: "She has some methodological concerns about the paper, including the use of local people—who might have opposed the occupation—as interviewers. She also points out that the result does not fit with any she has recorded in 15 years of studying conflict zones. Even in Darfur, where armed groups have wiped out whole villages, she says that researchers have not recorded the 500 violent deaths per day that the Johns Hopkins team estimates are occurring in Iraq. But overall Guha-Sapir says the paper contains the best data yet on the mortality rate in Iraq." A subsequent article co-authored by Guha-Sapir and Olivier Degomme for CRED reviewed the Lancet data in detail. It concluded that The Lancet overestimated deaths and that the war-related death toll was most likely to be around 125,000 for the period covered by the Lancet study, reaching its conclusions by correcting errors in the 2006 Lancet estimate and triangulating with data from IBC and ILCS.

Beth Osborne Daponte, a demographer known for producing death estimates for the first Gulf War, evaluated the Lancet survey and other sources in a paper for the International Review of the Red Cross. Among other criticisms, Daponte questioned the reliability of pre-war estimates used in the Lancet study to derive its "excess deaths" estimate, and the ethical approval for the survey. She concluded that the most reliable information then available was provided by the Iraq Family Health Survey, the Iraq Living Conditions Survey and Iraq Body Count.

Borzou Daragahi Iraq correspondent for the Los Angeles Times, in an interview with PBS, questioned the study based on their earlier research in Iraq, saying, "Well, we think—the Los Angeles Times thinks these numbers are too large, depending on the extensive research we've done. Earlier this year, around June, the report was published at least in June, but the reporting was done over weeks earlier. We went to morgues, cemeteries, hospitals, health officials, and we gathered as many statistics as we could on the actual dead bodies, and the number we came up with around June was about at least 50,000. And that kind of jibed with some of the news report that were out there, the accumulation of news reports, in terms of the numbers killed. The U.N. says that there's about 3,000 a month being killed; that also fits in with our numbers and with morgue numbers. This number of 600,000 or more killed since the beginning of the war, it's way off our charts."

The October 2006 Lancet estimate also drew criticism from the Iraqi government. Government spokesman Ali Debbagh said, "This figure, which in reality has no basis, is exaggerated". Iraq's Health Minister Ali al-Shemari gave a similar view in November 2006: "Since three and a half years, since the change of the Saddam regime, some people say we have 600,000 are killed. This is an exaggerated number. I think 150 is OK."

A 2010 paper by Professor Michael Spagat entitled "Ethical and Data-Integrity Problems in the Second Lancet Survey of Mortality in Iraq" was published in the peer reviewed journal Defense & Peace Economics. The paper argued that there were several "ethical violations to the survey's respondents", faults the study authors for "non-disclosure of the survey's questionnaire, data-entry form, data matching anonymised interviewer identifications with households and sample design", and presented "evidence relating to data fabrication and falsification, which falls into nine broad categories." The paper concluded that the Lancet survey, "cannot be considered a reliable or valid contribution towards knowledge about the extent of mortality in Iraq since 2003."

AAPOR investigation of the 2nd Lancet survey

On 3 February 2009, the Executive Council of the American Association for Public Opinion Research (AAPOR) announced that an 8-month investigation found the author of the 2006 Lancet survey, Dr. Gilbert Burnham, had violated the Association's Code of Professional Ethics & Practices by repeatedly refusing to disclose essential facts about his research. "Dr. Burnham provided only partial information and explicitly refused to provide complete information about the basic elements of his research," said Mary Losch, chair of the association's Standards Committee.

AAPOR's President, Richard A. Kulka, added:

<blockquote>When researchers draw important conclusions and make public statements and arguments based on survey research data, then subsequently refuse to answer even basic questions about how their research was conducted, this violates the fundamental standards of science, seriously undermines open public debate on critical issues, and undermines the credibility of all survey and public opinion research. These concerns have been at the foundation of AAPOR's standards and professional code throughout our history, and when these principles have clearly been violated, making the public aware of these violations is in integral part of our mission and values as a professional organization.</blockquote>

AAPOR subsequently released a more detailed list of eight specific pieces of information Burnham failed to disclose after repeated requests. These include a copy of the survey questionnaire in all languages into which it was translated, the consent statement, information of sample selection methodology and a summary of the disposition of all sample cases.

Neither Dr. Burnham nor the Johns Hopkins Bloomberg School of Public Health are members of AAPOR. Tim Parsons, public affairs director of the Bloomberg School wrote in an official statement that the school was "not in a position to comment" on AAPOR's findings because the school is not a member of the organisation and "does not know what procedures or standards were followed in reaching the decision regarding this study." Parsons also noted that the school was nearing completion of its own investigation into the study.

At least one article has been written critical of AAPOR's decision to censure Burnham. Debora MacKenzie, writing in New Scientist, said "There is no direct evidence that the latest attack on Burnham is politically motivated," but the APPOR's stated purpose, "to ensure survey-based research meets high standards," has itself "been questioned by experts." which MacKnenzie does not name.

<blockquote>According to New Scientist investigation... Burnham has sent his data and methods to other researchers, who found it sufficient. A spokesman for the Bloomberg School of Public Health at Johns Hopkins, where Burnham works, says the school advised him not to send his data to AAPOR, as the group has no authority to judge the research. The "correct forum", it says, is the scientific literature.</blockquote>

According to MacKenzie, "Burnham's complete data, including details of households, is available to bona fide researchers on request." She further noted that the AAPOR's own journal, Public Opinion Quarterly, "published an analysis of Burnham's Iraq survey by David Marker of Westat, a consultancy in Maryland that designs surveys."</blockquote>

On 1 February 2010, The Bloomberg School and Dr. Burnham were named for the

<blockquote>STONEWALLING/COVERUP" award in iMediaEthics' 2010 Top Ten "Dubious Polling" Awards, based largely on the AAPOR censure. The authors David W. Moore and George F. Bishop, write that Bloomberg and Burnham received the award, "for stonewalling in the face of serious questions about a flawed survey project, which reported more than 600,000 Iraqi deaths from 2003 to 2006," saying, "AAPOR asked for the kind of information that any scientist doing this type of work should release ... The Bloomberg School will not attempt to evaluate what experts believe is almost certainly a faulty methodology, saying the scientific community should make the evaluation. But then the school advises Burnham not to release details about his methods, so the scientific community can't have the information it needs for a definitive assessment. Sounds like a cop-out and a Catch 22, all rolled into one!</blockquote>

Johns Hopkins Investigation of the 2nd Lancet survey

In February 2009 Johns Hopkins Bloomberg School of Public Health published the results of an internal review of the study. The review found that researchers in the field used data collection forms that were different from those approved in the original protocol. The forms used in the field contained spaces for names of respondents or householders and many such names were collected, in violation of the protocol. The press release said the review did not find evidence that any individual was harmed as a result of these violations, and that no identifiable info was ever out of the possession of the researchers. As a result of their investigation, Hopkins suspended Dr. Burnham's privileges to serve as a principal investigator on projects involving human subjects research.

The press release also discussed an examination of all the original data collection forms:

<blockquote>An examination was conducted of all the original data collection forms, numbering over 1,800 forms, which included review by a translator. The original forms have the appearance of authenticity in variation of handwriting, language and manner of completion. The information contained on the forms was validated against the two numerical databases used in the study analyses. These numerical databases have been available to outside researchers and provided to them upon request since April 2007. Some minor, ordinary errors in transcription were detected, but they were not of variables that affected the study's primary mortality analysis or causes of death. The review concluded that the data files used in the study accurately reflect the information collected on the original field surveys.</blockquote>

Number of clusters

Steven E. Moore, who conducted survey research in Iraq for the Coalition Provisional Authority and was an advisor to Paul Bremer for the International Republican Institute, ridiculed the Lancet study in an 18 October 2006 editorial in the Wall Street Journal. In a piece entitled, "655,000 War Dead? A bogus study on Iraq casualties", Moore wrote, "I wouldn't survey a junior high school, no less an entire country, using only 47 cluster points. Neither would anyone else..."

Gilbert Burnham replied on 20 October 2006:

<blockquote>Mr. Moore did not question our methodology, but rather the number of clusters we used to develop a representative sample. Our study used 47 randomly selected clusters of 40 households each. In his critique, Mr. Moore did not note that our survey sample included 12,801 people living in 47 clusters, which is the equivalent to a survey of 3,700 randomly selected individuals. As a comparison, a 3,700-person survey is nearly 3 times larger than the average U.S. political survey that reports a margin of error of ±3%.

</blockquote>

Pre-invasion death rate

Fred Kaplan, writing for Slate, has criticised the pre-invasion death rate used in both the 2004 and 2006 Lancet surveys.

In an 29 October 2004 article in Slate he wrote:

<blockquote>But there are two problems with this calculation. First, Daponte (who has studied Iraqi population figures for many years) questions the finding that prewar mortality was 5 deaths per 1,000. According to quite comprehensive data collected by the United Nations, Iraq's mortality rate from 1980–85 was 8.1 per 1,000. From 1985–90, the years leading up to the 1991 Gulf War, the rate declined to 6.8 per 1,000. After '91, the numbers are murkier, but clearly they went up. Whatever they were in 2002, they were almost certainly higher than 5 per 1,000.

In an 20 October 2006 Slate article Fred Kaplan wrote that the pre-invasion death rate calculated by the 2006 Lancet report authors was also too low. This he said would cause the Lancet estimate of excess deaths since the invasion to be too high. Fred Kaplan wrote:

<blockquote>Based on the household surveys, the report estimates that, just before the war, Iraq's mortality rate was 5.5 per 1,000. (That is, for every 1,000 people, 5.5 die each year.) The results also show that, in the three and a half years since the war began, this rate has shot up to 13.3 per 1,000. So, the 'excess deaths' amount to 7.8 (13.3 minus 5.5) per 1,000. They extrapolate from this figure to reach their estimate of 655,000 deaths. However, according to data from the United Nations, based on surveys taken at the time, Iraq's preinvasion mortality rate was 10 per 1,000.</blockquote>

In a 20 November 2006 Slate article, 2 of the Lancet study authors, Gilbert Burnham and Les Roberts, write:

<blockquote>Kaplan claims that the rate was really 10, according to U.N. figures. He wrote, '[I]f Iraq's pre-invasion rate really was 5.5 per 1,000, it was lower than almost every country in the Middle East, and many countries in Europe.' This is just wrong! If Kaplan had checked the U.N. death-rate figures, most Middle Eastern nations really do have lower death rates than most European countries, and in fact have lower death rates than 5.5. Jordan's death rate is 4.2, Iran's 5.3, and Syria's 3.5. The reason for the lower rate is simple: Most Middle Eastern nations have much younger populations compared to most Western nations.</blockquote>

From a 19 October 2006 Washington Post article in The Times, economist Michael Spagat says there is a perplexing finding in the 2006 Lancet report that child deaths have fallen.

A 25 May 2000 BBC article reported that before Iraq sanctions were imposed by the UN in 1990, infant mortality had "fallen to 47 per 1,000 live births between 1984 and 1989. This compares to approximately 7 per 1,000 in the UK." The BBC article was reporting from a study of the London School of Hygiene & Tropical Medicine, titled "Sanctions and childhood mortality in Iraq", that was published in the May 2000 Lancet medical journal.

The 2000 BBC article reported that after the UN sanctions were imposed after Iraq's 1990 invasion of Kuwait, "They found that in south and central Iraq, infant mortality had risen to 108 per 1,000 between 1994 and 1999, while child mortality—covering those between one and five years—rocketed from 56 to 131 per 1,000."

The 2000 BBC article also reported, "However, it found that infant and child mortality in the autonomous, mainly Kurd region in the North of the country, has actually fallen, perhaps reflecting the more favourable distribution of aid in that area."

UN-sponsored studies taken after 2003 revealed that the previous childhood mortality figures for South/Central Iraq (supplied by Saddam's government) were inflated by more than a factor of two and that the childhood mortality rate in those regions was even lower than the rate in northern Iraq.

The UN sanctions ended on 22 May 2003 (with certain arms-related exceptions).

40 houses surveyed per day

Madelyn Hicks, a psychiatrist and public health researcher at King's College London in the UK, says she "simply cannot believe" the paper's claim that 40 consecutive houses were surveyed in a single day. "There is simply not enough time in the day," she says, "so I have to conclude that something else is going on for at least some of these interviews." Households may have been "prepared by someone, made ready for rapid reporting," she says, which "raises the issue of bias being introduced."

An 24 October 2006 The Guardian article reports this response from Lancet study author Gilbert Burnham:

<blockquote>Others had suggested that it was impossible for 40 households to be surveyed in one day—but in fact the researchers were split into two teams and conducted 20 household interviews each, he said.</blockquote>

Death certificates

Of the 1849 households that completed the survey there were reports of 629 deaths during the study period from 1 January 2002 through June 2006.

The Iraq Body Count project questioned the Lancet study's death certificate findings saying the Lancet study authors "would imply that officials in Iraq have issued approximately 550,000 death certificates for violent deaths (92% of 601,000). Yet in June 2006, the total figure of post-war violent deaths known to the Iraqi Ministry of Health (MoH), combined with the Baghdad morgue, was approximately 50,000."

The August 2006 Basrah Governorate Assessment Report of the United Nations High Commissioner for Refugees described death certificate procedures of the Ministry of Health (MoH) as follows:

<blockquote>Death certificates, which are needed in order to obtain retirement benefits for a person's surviving spouse or children, as well as for inheritance purposes, are issued by the MoH Births/Deaths Administrative Offices which are located in Public Hospitals. Death certificates are usually issued the same day. The following documents are required:

:*Medical report;

:*Civil ID card of the deceased person;

:*Food ration card of the deceased person.

:The issuance of death certificates is free.</blockquote>

In a 20 November 2006 Slate article, 2 of the Lancet study authors, Gilbert Burnham and Les Roberts, write:

<blockquote>In July [2006], for example, the Ministry of Health reported exactly zero violent deaths in Anbar Province, in spite of the contradictory evidence we saw on our televisions. Is that a surveillance network on which our understanding of what is going on in Iraq can depend?</blockquote>

In a peer-reviewed paper on the Lancet survey, economist Michael Spagat examined the death certificate data. He noted that the very high reported rate of death certificates by the survey "implies that the official death certificate system has issued, but failed to record the issuance of, about 500,000 death certificates", and notes that the rate of confirmations claimed by the second survey is substantially higher than the rate found in the first survey, despite covering a longer period, and calculates the odds against this to be very high. Spagat further notes several "unlikely patterns in the confirmations of violent deaths through the viewing of death certificates and in the patterns of when death certificates were requested and when they were not requested." His analysis concludes that "there is likely fabrication in the death-certificate data" and that "these data do not give reliable support to [the Lancet survey's] very high estimated death rate."

These professors have published a detailed paper discussing this bias and the Lancet study called "Conflict Mortality Surveys".

An 24 October 2006 The Guardian article reported this response from a Lancet study author:

<blockquote>But Prof Burnham said the researchers penetrated much further into residential areas than was clear from the Lancet paper. The notion 'that we avoided back alleys was totally untrue'. He added that 28% of households were in rural areas—which matches the population spread.

Bohannon defended his comments as accurate, citing Burnham saying, in response to questions about why details of selecting "residential streets that did not cross the main avenues", that "in trying to shorten the paper from its original very large size, this bit got chopped, unfortunately." In addition, the details which were destroyed refer to the "scraps" of paper on which streets and addresses were written to "randomly" choose households.

The authors of the main street bias critique published a formal paper on this idea in the Journal of Peace Research. This paper subsequently won the journal's 2008 Article of the Year award. The jury states that the article "provides an important advance in the methodology for estimating the number of casualties in civil wars," and that, "the authors show convincingly that previous studies which are based on a cross-street cluster-sampling algorithm (CSSA) have significantly overestimated the number of casualties in Iraq."

The authors have also published a follow-up paper in Europhysics Letters which provides a generic framework than can be used to assess sampling bias in certain social and biological systems. A special case of the framework can be used to derive the results presented in their Journal of Peace Research paper. The authors also investigate the sensitivity of their results to the underlying model parameter values. They reiterate their view that a more precise determination of the model parameters and, hence, the extent of sampling bias, is possible only if the actual micro-level data of the Lancet study are released.

Criticism of graph

thumb|500px|right|Figure 4 from the second The Lancet survey of Iraqi mortality, showing a comparison with two other mortality estimates. Two letters subsequently published in the Lancet journal challenged this graph as erroneous and misleading, and the authors of the study conceded these problems, saying that they intended to illustrate their similar escalation.

Figure 4 from the October 2006 Lancet survey of Iraq War mortality, showing a comparison of 3 mortality estimates. Two letters subsequently published in the Lancet journal challenged this graph.

The article's authors defended their research, stating that their work was the only active study of the death toll, and that this is more accurate than passively counting reported deaths.

A Reuters article reported on other researchers, epidemiologists, professors, and physicians who had defended the study. For example, the article stated:

<blockquote>"Over the last 25 years, this sort of methodology has been used more and more often, especially by relief agencies in times of emergency," said Dr. David Rush, a professor and epidemiologist at Tufts University in Boston.</blockquote>

Sir Richard Peto, Professor of Medical Statistics and Epidemiology in the University of Oxford, described the 2006 report as "statistically valid" in an interview on BBC television.

Dr. Ben Coghlan, an epidemiologist in Melbourne Australia, wrote:

<blockquote>The US Congress should agree: in June this year [2006] they unanimously passed a bill outlining financial and political measures to promote relief, security and democracy in the Democratic Republic of Congo. The bill was based in part on the veracity of a survey conducted by the Burnet Institute (Melbourne) and the International Rescue Committee (New York) that found 3.9 million Congolese had perished because of the conflict. This survey used the same methodology as Burnham and his associates. It also passed the scrutiny of a UK parliamentary delegation and the European Union.</blockquote>

Burnham is one of the authors of both of the Lancet studies.

A 19 October 2006 Washington Post article reported:

<blockquote>A review of a variety of mortality estimates for Iraq was made by a group of scientists and published in 2008 in Conflict and Health, a peer-reviewed journal; their conclusion is that the Lancet "studies provided the most rigorous methodology as their primary outcome was mortality.</blockquote>

UNDP ILCS study compared to Lancet studies

UNDP ILCS stands for the 2004 United Nations Development Programme Iraq Living Conditions Survey

The Iraq Body Count project (IBC) records civilian deaths reported by English-language media, including all civilian deaths due to coalition military action, the insurgency or increased criminal violence. The IBC site states: "many deaths will likely go unreported or unrecorded by officials and media."

The IBC death count at the time of the October 2006 Lancet study was released was between 43,546 and 48,343, or roughly 7% of the estimate in the Lancet study. Besides the admitted IBC undercount due to its media reliance, some of the difference between the Lancet and IBC estimates is explained by the fact that the Lancet study was estimating all "excess" deaths from any and all violent and nonviolent causes, and includes combatants and civilians alike.

However, IBC believes some of it may also be explained by the Lancet having overestimated, citing the lower estimate from the UNDP's 2004 Iraq Living Conditions Survey (ILCS).

IBC illustrated several of what it calls "the main data that are relevant to a comparative assessment of" the ILCS study and the 2004 Lancet study. It points to, for example, a much larger number of clusters (2,200 for ILCS vs. 33 for Lancet), and a more accurate sampling rate (1 in 200 for ILCS vs. 1 in 3,000 for Lancet). The 2006 Lancet study is somewhat larger than the first (it used 47 clusters instead of 33, and had a lower sampling rate). The 2004 Lancet study surveyed 988 households, and the 2006 Lancet study surveyed 1849 households. The ILCS study surveyed 22,000 households.

Lancet authors draw a different kind of comparison. From Appendix C of the 2006 Lancet study supplement It states:

<blockquote>The ILCS data has been derived from a question posed to households concerning missing and dead persons during the two years prior to the survey. Although the date was not asked for, it is reasonable to suppose that the vast majority of deaths due to warfare occurred after the beginning of 2003.</blockquote>

Iraq Body Count project compared to Lancet studies

Besides the comparisons made in various publications,

On 28 January 2008, ORB published an update based on additional work carried out in rural areas of Iraq. Some 600 additional interviews were undertaken and as a result of this the death estimate was revised to 1,033,000 with a given range of 946,000 to 1,120,000.

This ORB poll estimate came under criticism in a peer reviewed paper called "Conflict Deaths in Iraq: A Methodological Critique of the ORB Survey Estimate" by Michael Spagat and Josh Dougherty, [from the IBC], published in the journal Survey Research Methods. This paper "finds fundamental flaws in the data underpinning ORB's estimate", and concludes that the ORB data "are not suitable for deriving any credible estimate but, given proper scrutiny, it is clear that ORB has overestimated by a wide margin."

Iraq Family Health Survey compared with Lancet studies

The "Iraq Family Health Survey" published in the New England Journal of Medicine surveyed 9,345 households across Iraq and estimated 151,000 deaths due to violence (95% uncertainty range, 104,000 to 223,000) over the same period covered in the second Lancet survey by Burnham et al. The NEJM article stated that the second Lancet survey "considerably overestimated the number of violent deaths" and said the Lancet results were, "highly improbable, given the internal and external consistency of the data and the much larger sample size and quality-control measures taken in the implementation of the IFHS."

Roberts says the discrepancy between the two studies arise with Lancet attributing most of the post-war excess deaths to violence, while only one-third of the excess deaths would be due to violence in the IFHS.

The authors of the IFHS report have disputed this conclusion, saying, "The excess deaths reported by Burnham et al. included only 8.2% of deaths from nonviolent causes, so inclusion of these deaths will not increase the agreement between the estimates from the IFHS and Burnham et al." They defended the results of their survey saying, "It is unlikely that a small survey with only 47 clusters has provided a more accurate estimate of violence-related mortality than a much larger survey sampling of 971 clusters."

See also

  • Casualties of the Iraq War. An overview of many casualty estimates.
  • ORB survey of Iraq War casualties
  • Iraq Family Health Survey

References

;First study

  • Elisabeth Rosenthal, "Study Puts Iraqi Deaths of Civilians at 100,000", International Herald Tribune via the New York Times, 29 October 2004.
  • Sarah Boseley, "100,000 Iraqi civilians dead, says study", The Guardian, 29 October 2004.
  • Stephen Soldz, "100,000 Iraqis Dead: Should We Believe It?", ZNet, 3 November 2004.
  • Jamie Doward, "The Lancet and the bodies in question", column in The Guardian, 7 November 2004.
  • Joseph Choonara, "Counting the dead in Iraq", interview of Les Roberts, Socialist Worker, 23 April 2005.
  • Les Roberts, "100,000 deaths in Iraq: A year later", American Friends Service Committee, 26 October 2005.
  • Les Roberts seminar at the London School of Hygiene & Tropical Medicine, on 13 April 2005; uploaded in https://www.youtube.com/watch?v=o5vD_Ub2K_c on 25 October 2006.

;Second study

  • "Co-Author of Medical Study Estimating 650,000 Iraqi Deaths Defends Research in the Face of White House Dismissal" (contains link to audio), interview with Les Roberts, Democracy Now, 12 October 2006.
  • "War on Iraq: Is the United States Killing 10,000 Iraqis Every Month? Or Is It More?". By Michael Schwartz. AlterNet. 6 July 2007.
  • "Data Bomb". By Neil Munro, National Journal, 4 January 2008.
  • Researchers Respond to National Journal Article. By Gilbert Burnham, MD, PhD, Professor and Director, Center for Refugee and Disaster Response, Johns Hopkins Bloomberg School of Public Health. And by Les Roberts, PhD, Associate Professor, Mailman School of Public Health, Columbia University.
  • "Right-Wingers Can't Cover Up Iraq's Death Toll Catastrophe". By John Tirman. 21 January 2008. AlterNet.
  • Answers to Questions About Iraq Mortality Surveys. The Center for Refugee and Disaster Response, of the Johns Hopkins Bloomberg School of Public Health.