The research was based on the previously established database of victims of World War II and the time immediately after it, created on the basis of a systematic review of the relevant literature and archive sources. By means of verification of data from this database on the basis of systematic reviews of death registers and partly also birth registers, the previously collected pieces of information were confirmed, amended, corrected or refuted. In many cases new victims were discovered; persons were excluded from the list of victims that turned out, on the basis of the review of the registers, to have actually survived the war; and the so-called double entries were also excluded. Around 60 % of persons from the current list of victims were verifiable, while the deaths of others had not been entered into the death registers or were not identifiable (for example, in the cases where the cause of death was not apparent). The verification of data proved to be an important research procedure in the efforts to establish as exact and realistic a number of victims as possible as well as their precise identification. Important new information was acquired about certain categories of victims, for which very deficient data had previously been collected.

The realisation of the project largely depended on field work; that is, on the reviews of registers in registry offices as well as local offices. In various areas of Slovenia, throughout the duration of the project, the project group reviewed civil registers at 31 administrative units, thus concluding the review of civil registers of all 58 administrative units of the RS. 381 days were invested in field work, and the rest of the time was spent in order to input entries into the computer database entitled Casualties among the population in the territory of the Republic of Slovenia during World War II and immediately after it. The information about the persons checked in the civil registers is gradually published at the www.sistory.si website. This list currently includes information about 50,870 victims of World War II.

The analysis of the data gathered proves that in comparison with other European countries Slovenia belongs among the regions severely affected by the war, while in the former Yugoslav context Slovenia is average in terms of damage. The list of victims currently includes 97,697 persons, whose deaths were related to wartime and post-war violence, which represents a loss of 6.5 % of the whole population. From the viewpoint of the loss of human lives, the historical processes were most radical in the Ljubljana Province, as the loss of population there amounted to 9.5 %, while this percentage was the lowest in the Prekmurje region, where 1.9 % of the population was killed. Most deaths were caused by the German occupiers, followed by the partisan and revolutionary camp. The largest number of deaths was suffered by the members of the partisan units and the civil population.