The coding of medical causes of death is the primary mission of Inserm’s CépiDc. This coding system underwent significant changes beginning with deaths recorded in the year 2000. First, the tenth revision of the International Classification of Diseases (ICD-10) replaced the ninth revision (ICD-9), which had been in use since 1979. The objective of this study is to analyze the impact of changes in the coding process since 2000 on trends in cause-specific mortality. Given the significant changes in the coding process starting with deaths in the year 2000, it is essential to document their impact on trends in recorded causes of death. This type of information is indispensable for all users of mortality data analyzing temporal trends in cause-specific death rates. These trend changes may be due to the change in classification (transition from ICD-9 to ICD-10) or to the change in coding method (transition from manual to automated coding).