Measuring deaths from conflict
Authors: Richard Garfield
Journal: BMJ (2008)

In the linked study, Obermeyer and colleagues challenge conventional thinking about deaths related to war and force us to re-evaluate some well established assumptions about these deaths.1 Deaths in combatants and non-combatants are always underestimated during conflicts between armed groups in poor countries that are not national armies.2 Even in middle income developing countries, counts that are purported to be precise fail to include most of those killed.3 4

Obermeyer and colleagues used demographic data from world health surveys collected before and after conflicts in 13 countries over the past 50 years. The surveys collect information from one respondent for each household about sibling deaths, including whether the deaths were related to war. The data are then compared with those obtained through passive reports (mainly from eyewitnesses and the media). This method eliminates some of the ambiguity rampant in this highly politicised field.

Obermeyer and colleagues estimate that 5.4 million (95% confidence interval 3.0 to 8.7) deaths occurred as a result of war in 13 countries from 1955 to 2002; the numbers ranged from 7000 in the Republic of Congo to 3.8 million in Vietnam. The estimates were about three times higher than those obtained from passive reports.

Limitations of the analysis include the relatively small number of surveys analysed (13) and the fact that five of them were based on relatively small national samples. Also, because undercounting varies greatly between conflicts, the confidence intervals are wide. The pattern of undercounting was not consistent—some countries even overcounted the number of deaths.

Good quality data on the epidemiology of violence often become available only years after the killing has ended. Real time surveillance systems that can count most deaths as they occur are needed to solve this problem. In poor and unstable countries, where almost all wars now occur, such systems are rare.

Despite rigorous efforts to correct for under-reporting, Obermeyer and colleagues could not correct for household members who chose not to report deaths. How the relevant questions were asked in face to face interviews can greatly influence the results obtained. Similarly, the total number of deaths in war may be grossly underestimated by multiyear demographic modelling. Half a million deaths can occur unnoticed when demographic models do not count actual deaths but depend on projections from count data that are decades old.

Finally, the study only includes violent deaths. In the poorest countries, where most conflicts now occur, a rise in deaths from infectious diseases often dwarfs the number of violent deaths during a conflict. For all these reasons, Obermeyer and colleagues’ study is likely to underestimate the importance of conflict as a cause of death.

To reduce casualties from violence or disease we need current data, as well as assessments of their inadequacies. A lack of such assessments has fuelled controversies over estimates of deaths in non-combatants that are based on data from field epidemiological studies in Iraq, Darfur Sudan, and the Democratic Republic of Congo. But we should not despair. A generation ago little controversy existed over such figures because epidemiological studies like these did not even exist.

The news about war related deaths in the world these days is both good and bad. The good news is that fewer combatants die today than at any time in the past 100 years, and the number and intensity of military conflicts have declined considerably since 1994.5 The bad news is that most excess deaths in areas of conflict in developing countries occur in non-combatants, and these deaths are often not counted, so we cannot be sure that the total number of war related deaths has also dropped.

The method pioneered by Obermeyer and colleagues is promising, however. When stability returns to current or recent hotspots where epidemiological study is difficult—such as Somalia, southern Sudan, and Iraq—we may yet be able to count the lives and deaths of these people. As the authors state in their introduction, the importance of war as a public health problem and a social problem makes this imperative.