Basic Health Indicators

Cases
Before understanding any of the following terms, it’s important to define what a case of a disease is, otherwise it is impossible to compare data. A case could be hospitalized patients or deaths. It can be either discrete (present or absent) or continuous (BP, serum cholesterol, intensity of infection)

Survival rate
Survival rate is the proportion of survivors in a specified group, usually patients with a disease, who survived in a specified period of time.

Lethality rate
Lethality = number of deaths / over number of sick with a specific disease (x100) It is also known as Case fatality rate. It is the proportion of cases in a designated population of a particular disease, which die in a specified period of time.

Note: lethality is a better measure of clinical significance of the disease than mortality. For example: Naegleria fowleri has a much higher lethality (it will surely kill you once you get it), than heart attacks who have a higher mortality, that is, more people die from heart attacks (due to much higher prevalence of cardiac disease) rather than from N. fowleri infection (very low prevalence).

Related articles

 * Descriptive Studies
 * Analytical Studies
 * Experimental Studies