Accuracy of death certification of stroke: the Framingham Study

The validity of death certification of stroke was studied in the general population cohort at Framingham, MA. During the last 30 years, 5106 people aged 30 to 62 and free of CHD and stroke at entry have been followed for the development of cardiovascular disease including stroke. Of the 280 decedents with certified stroke 113 (40% false negative rate) had no mention of stroke on the death certificate. THe false negative rate increased significantly with increasing age at death and increasing interval from last stroke to death. Among the 216 certificates listing stroke there were 46 false positives (21%). Analysis by type of stroke disclosed marked over-reporting of cerebral hemorrhage and under-reporting of cerebral embolus. This comparison of prospectively collected data to death certificates should raise questions about the accuracy of studies dependent on ths source of information.