Effect of measurement on sex difference in stroke mortality.

The 1994 to 1997 administrative data on 40 450 elderly Medicare beneficiaries and general population of 2 states were used to measure "case mortality" (deaths attributable to any cause among cases of acute stroke), "case fatality" (deaths caused by cerebrovascular diseases among cases of acute stroke), and "population mortality" (deaths caused by stroke in the elderly general population). Mortality was higher in men than in women according to all measures except population mortality caused by subarachnoid hemorrhage. There was no sex difference in 1-year case fatality. One-year all-cause mortality among cases of nonhemorrhagic stroke or all types of stroke was higher in men than in women. Similar sex differences were found in 4-year population mortality caused by nonhemorrhagic stroke or all types of stroke combined. The 3 measures differed with respect to sex difference in stroke mortality. How stroke is defined and how mortality is measured does affect sex difference.