The paper found that most deaths during the period were, "inflicted by unknown perpetrators, primarily through extrajudicial executions." The paper also utilized what the authors refer to as the "Dirty War Index" which evaluates the behavior of different perpetrators or weapon types in terms of the proportion of women and children killed, with higher DWI ratios suggesting tactics or weapons that are more indiscriminate toward civilians. The study found that unknown perpetrators firing mortars had the highest DWI ratio, followed by Coalition Forces air attacks, leading the authors to advise that such weapons should not be used in populated areas.[16]