Changing trends in the diagnosis of sudden infant death.

A study of 114 consecutive cases of unexpected infant death that occurred in South Australia over a 5-year period from January 1994 to December 1998 was undertaken. There were 45 deaths attributed to sudden infant death syndrome (SIDS), 19 to natural causes, 21 to accidents. and 5 to homicides; 24 cases were listed as "undetermined." Although there has been a genuine and continued decline in SIDS numbers in this population, there has also been an increase in the diagnosis of cases of accidental asphyxia due to unsafe sleeping environments and of cases in which the family background and autopsy findings suggested more complex mechanisms. The change in diagnostic profile has followed the introduction of more rigorous clinical history review, death scene examination, and autopsy testing. Thus, although diagnostic outcomes have altered in this population, it is more likely the result of more careful interpretation of the extensive investigations that are now undertaken rather than arbitrary reclassification.