Prevalence
Prevalence, sometimes referred to as prevalence rate, is the proportion of persons in a population who have a particular disease or attribute at a specified point in time or over a specified period of time
“Point prevalence” is the proportion of a population that has the condition at a specific point in time. “Period prevalence” is the proportion of a population that has the condition at some time during a given period (“12-month prevalence”, etc.), and includes people who already have the condition at the start of the study period as well as those who acquire it during that period. “Lifetime prevalence” (LTP) is the proportion of a population that at some point in their life (up to the time of assessment) have experienced the condition.
Prevalence estimates are used by epidemiologists, health care providers, government agencies, and insurers.
Prevalence is contrasted with incidence, which is a measure of new cases arising in a population over a given period (month, year, etc.). The difference between prevalence and incidence can be summarized thus: prevalence answers “How many people have this disease right now?” and incidence answers “How many people per year newly acquire this disease?”.
Low back pain is one of the most common ailments faced by the general adult population at a prevalence rate of 84 % 1).