Building on the existing body of evidence, Salomon and Murray (2002), further add nuances to the traditional theory of epidemiological transition by disintegrating it based on disease categories and different age-sex groups, positing that the epidemiological transition entails a real transition in the cause composition of age-specific mortality, as opposed to just a transition in the age structure. Using Global Burden of Disease data from 1990, they disintegrate the transition across three cause groups: communicable diseases, non-communicable diseases and injuries, seeking to explain the variation in all-cause mortality as a function of cause-specific mortality in 58 countries from 1950 to 1998. This analysis validates the underlying premise of the classic epidemiological transition theory: as total mortality declines and income rises, communicable diseases cause less and less mortality compared to non-communicable diseases and injuries. Decomposing this overall impact by age-sex groups, they find that for males, when overall mortality decreases, the importance of non-communicable diseases (NCDs) increases relative to the other causes with an age-specific impact on the role of injuries, whereas for women, both NCDs and injuries gain a more significant share with mortality decreases. For children over one year, they find that there is a gradual transition from communicable to non-communicable diseases, with injuries remaining significant in males. For young adults, the epidemiological transition is particularly different: for males, there is a shift from injuries to NCDs in lower income settings, and the opposite in higher-income settings; for females, rising income also signifies a shift from NCDs to injuries, but the role of injuries becomes more significant over time compared to males. Finally, for both males and females over 50, there is no epidemiological transition impact on the cause composition of mortality.