Objective To evaluate the influence of the tenth revision of the International Statistical Classification of Diseases (ICD-10) on tendencies of annual mortality rates, corrected and uncorrected to the ICD-9.
Methods Starting with the causes with a significant comparability ratio, we calculated the annual ageadjusted rates from 1980 to 2004. The comparability ratio was applied to the rates for 1999�2004, obtaining the corrected series for the whole period. This series was then compared with the uncorrected series using joinpoint regression.
Results Mortality decreased between 1999 and 2004. Differences were found in blood diseases, hypertensive diseases, cancer of illdefined sites, respiratory insufficiency, and myelodysplastic syndrome.
Conclusions The tendency of the main causes of mortality has been largely unaffected by the revisions in the ICD-10, except in infrequent or less specific diseases.