The value of autopsies for determining the cause of death.

BACKGROUND Death certificates are the only source of information on the underlying cause of death in more than 90 % of cases. Supplementary information is available for only a small proportion of them, as a rule from a medical or forensic autopsy. We wished to investigate how frequently the findings of medical autopsies influence determination of the underlying cause of death. MATERIAL AND METHOD Using the Norwegian Cause of Death Register as our basis, we determined from the death certificate the underlying cause of death for deaths for which a medical autopsy was carried out in 2005. Then we investigated whether the underlying cause of death was changed when we took account of the autopsy findings. RESULTS There were 41,152 deaths in Norway in 2005. The Cause of Death Registry received the results of medical autopsies for 1 773 persons who died at the age of 2 or older. Autopsy findings led to changes in the underlying cause of death in 1,077 cases (61 %). In 567 cases (32 %), the change was a major one, resulting in a change in the ICD 10 chapter for cause of death. The percentage of changed causes of death was greatest for the youngest and oldest age groups and for women. INTERPRETATION Medical autopsies provide an important corrective to the determination of underlying cause of death.