1.2 Methodology for the Calculation of Estimated Homicide
In Brazil, there are two main sources that provide data on homicides: the reports or records of police occurrences and the death certificates compiled by the Ministry of Health that are provided by the SIM (Mortality Information System). This information is not necessarily coincidental, even though they have high correlation with each other. In addition, both sources have certain problems of validity and reliability.
For many reasons, the data from the Ministry of Health are considered more consistent and reliable, often being used more, especially in places where the police don’t have conditions to maintain systematic and controlled processes for recording and processing of information.
In the case of information from the Municipal Health Departments, the major problem for working with homicide is related to deaths that are due to external causes with intentionality unknown. That is, deaths in which it is not known whether they were caused accidentally (accidents) or intentionally (homicide and suicides). The proportion of these cases varies greatly among states and municipalities. It is therefore important to work with estimations that consider other categories in addition to deaths classified directly as a result of aggression.
Many authors call attention to the need to apply a kind of correction to the records of homicides reported by the Health System. These corrections are intended to reduce a possible underestimation of deaths from unknown cause, since in the details of the underlying cause of death, many homicides can be mistakenly allocated in this category (Lait, 1992; Cruz, 1996; Lozano, 1997; Cruz e Souza, 1998; Cano and Santos, 2001).
In this research, the proposal elaborated by Cano and Santos (2001) was adopted. They considered all deaths from firearms or sharp instruments, both accidental as the ones with intent unknown, as intentional, and then distributed these deaths into homicides and suicides respecting the ratio of these two causes between the cases with known intent. In Latin America, this ratio is approximately 95% for homicides and only 5% for suicides. In addition, 10% of deaths with intent unknown committed by other means were considered homicides.
In short, the table below shows the CID-10 codes that were considered for calculating the estimated number of homicides:
