Measure of Disease Occurrence Flashcards
Measures of health status convey information about
the occurrence of disease
Measures of Health Status includes
Counts
Proportions
Ratios
Rates
Simplest/most frequently performed measure in epidemiology & refers to the number of cases of a disease
Counts
Counts are useful for
allocation of health resources
Counts have Limited usefulness for epidemiologic purposes without
Knowing size of the source population
Proportions rule:
Persons included in the numerator are always
included in the denominator
In epidemiology proportions tells us
The fraction of the
population that is affected
Numerical value of a proportion
0 to 1.0
Like a proportion, a ratio is
a fraction, BUT without a specified
relationship between the numerator and denominator
Epidemiologic rates contain the following elements
Disease frequency (in the numerator)
Unit size of population
Time period during which an event occurs
Rate is identified as
A ratio in which TIME forms part of the denominator
The development of new cases of a
disease that occur during a specified
period of time
Incidence
Incidence quantifies the
development of disease
What is the Most fundamental measure of disease frequency and leads to the development of the concept of risk
Incidence
What are the two type of incidence
Cumulative incidence (Cl) - Incidence proportion
Incidence Rate (IR) - Incidence density
PROPORTION of individuals who become diseased during a specified period of time
Cumulative incidence
Cumulative incidence is also refered to as the
Incidence proportion
Cumulative incidence is represented as
Number of new cases of disease during a given period/ Total population at risk during given period
To accurately calculate cumulative incidence
follow the entire population
Cumulative incidence provides an estimate of
probability (risk) that an individual will develop a disease during a specified period of time.
