[Underlying cause of death from external causes: validation of official data in Recife, Pernambuco, Brazil].

OBJECTIVE: To validate the underlying cause of death recorded on the death certificates for individuals under 20 years of age who died from external causes in 1995 in Recife, Pernambuco, Brazil.
METHODS: We divided the study into two stages, coding and validation. In both stages we compared the official data concerning causes of death to the data we obtained during our study. We grouped the death certificates into 5 broad categories according to the cause of death; we later subdivided them into 14 categories. We also individually compared the death certificates applying the four-digit system of the International Classification of Diseases, Ninth Revision (ICD-9). We assessed the agreement between the official data and our data in terms of sensitivity and the kappa coefficient. We took as the standard the categorization of the cause of death that we had made during our investigation.
RESULTS: In the coding stage, considering all the external causes of death, the overall agreement between the official data and our study data was 94% for the 5 categories, 92% for the 14 categories, and 81% for the four-digit ICD-9 system. In the validation stage the overall agreement was 94% for the 5 categories, 91% for the 14 categories, and 73% for the four-digit ICD-9 system.
CONCLUSIONS: Our results suggest that for the death certificates to be reliable, the Institute of Legal Medicine must fill them out following recommended standards. In addition, hospitals and police departments must use greater care in completing the transfer slips that accompany the bodies that are sent to the Institute. More accurate data need to be generated and disseminated for a society to better understand its patterns of violence.