They compared the preautopsy cause of death, as determined by a thorough review of the clinical data and circumstances, to the autopsy-derived cause of death. In the majority (91/100), the preautopsy and postautopsy proximate causes of death were in agreement. In 9 percent, the autopsy provided information that resulted in a proximate cause of death different than anticipated. In four instances, the manner of death also was incorrect and was determined to be an accident rather than the originally presumed natural. No homicide or suicide would have been misclassified. In another nine instances, where the premortem and postmortem proximate causes of death were in agreement, the autopsy provided a specific mechanism of death. With a quality initial medicolegal death investigation, a subset of sudden deaths in adults may be reliably certified without an autopsy. 2 tables and 30 references (Published abstract)