A study based on the Iraq Family Health Survey (IFHS) and recently published in the New England Journal of Medicine sheds new light on violent deaths in Iraq. It estimates that violent deaths are 2-4 times higher than the tally of civilian deaths collected from media reports by Iraq Body Count (IBC). This disparity is unsurprising, since that tally attempts to screen out combatant deaths, and media reports will miss some deaths. The study period ended in June of 2006: applying the same ratio to the current IBC tally would give a death toll in the 150,000-300,000 range.
This fits with the earlier ILCS survey, which estimated violent deaths 2-3 times the contemporary IBC count. This estimate based on cemetery traffic suggests a ratio in the 2.5-4.5 times range.
The study by Burnham et al published in The Lancet estimated violent deaths 10-20 times higher than IBC. There’s an obvious conflict between Burnham et al and IFHS. IFHS had a larger sample size, more resources and better supervision. Both studies failed to survey some of the planned clusters: 11% in IFHS, 6% in Burnham et al. IFHS made an effort to compensate for the missed clusters, Burnham et al did not. IFHS also made an effort to reflect regional population changes from migration during the study period. Burnham et al did not.
Some supporters of Burnham et al are still defending that study. One argument they make is that IFHS isn’t so different if you measure “excess death,” that is the increase in death rates, including nonviolent deaths, over pre-war conditions. I don’t think this works: the IFHS authors didn’t try to calculate that and argued, I think correctly, that recall was worse for the pre-war period. Certainly the recalled death rate for that period was low compared to neighboring countries. Subtracting the pre-invasion death-rate from the post invasion rate could give a spurious increase because of recall issues.
Supporters of Burham et al also complain that the IFHS annual death rate does not show the strong increase from 2003 to 2006 recorded in other sources. However, the range of sampling error is substantial for the annual figures, and the difference in the IFHS trendline and that shown by IBC is not statistically significant.
One of the strengths of the IFHS data is that it also looked at other demographic data, and the large sample size narrowed the margin of error. If Burnham et al was closer to the truth about violent deaths than IFHS, the result should be visible in the IFHS demographic data. If 2.5% of the population is being killed in an armed conflict, (as Burnham et al claim) and most of those deaths are military-age males (one of the few points on which Burnham et al and IBC agree), then the result should be a strong male/female imbalance in adult Iraqi demographics.
The predicted imbalance does not occur in the IFHS data, except for the cohort that was unfortunate enough to reach fighting age back when Saddam Hussein was invading his neighbors.