Mortality is a traditional health indicator, actually better understood as a measure of “non-health”. Although quantifying irreversible events, mortality statistics are an important pillar of health information systems, providing unique information for public health guidance, such as :

• the importance of severe health problems,
• their evolution over time,
• disparities in groups of population, pointing out health inequalities,
• threat detection,
• the efficiency of public health actions.

Mortality statistics address various aspects of mortality. They include two main areas:

• All-cause/general mortality indicators such as life expectancy, excess mortality, crude or adjusted mortality rates
• Monitoring of the causes of death

The study of causes of death is crucial to support health policy by identifying and ranking the most life-threatening conditions. In particular, focusing on the causes of death that could be prevented through the health system or health-related policies helps to identify which problems should be prioritized, and therefore facilitates planning of interventions. Other indicators, such as the probability of dying from a specific diseases (Case Fatality Ratio or lethality ratio) or the burden of disease can therefore being estimated, as can the relationship between mortality for certain causes and environmental or meteorological risk factors.