The Extent of Misclassification of Accidents and Deaths of Undetermined Intention on the Suicide Rate, Sweden 1950-2000

Julianne K. Ohlander, University of California, Irvine

It is widely accepted in mortality research that there exists some misclassification of causes of death. Misclassification is a longstanding concern in suicide research. External cause-of-death data from 1950-2000 are examined to determine the impact of the 1969 introduction of deaths of "undetermined intention" to the International Classification of Diseases on the suicide rates in Sweden. The current practice in Sweden is to include all deaths of undetermined intent in the suicide rate, which is not without faults. Using official mortality data from 1950 to 2000, this paper seeks to answer (1) Were suicides over- or under-estimated before the introduction of the uncertain intention death category? (2) From which external cause-of-death categories are the undetermined deaths from 1969 and onward being drawn? (3) To what extent, if any, is the suicide rate erroneously inflated by this practice? Results are presented for the total population and separately for males and females.