Epidemiologic Risk Measures Flashcards
Epidemiology
study of distribution and determinants of disease, injury or dysfunction
Public health problems or events Epidemiologists investigate
Environmental exposures Infectious diseases Injuries Non-infectious diseases Natural disasters Terrorism
Descriptive epidemiologic study
Used when little is known about occurrence or determinant of health conditions
presented as case reports, correlational studies, or survey studies
Descriptive epidemiologic studies purposed to answer:
who experiences the disorder?
where is frequency highest or lowest?
When does the disorder occur most or least frequently?
Prevalence / Incidence
Prevalence
(# existing cases of a disease at a given point in time) / (total population at risk)
estimate of probability that an individual will have a particular disorder at that time
Point Prevalence
reflects cross sectional status of the population
Period prevalence
combines existing cases with new cases during the period of ONE YEAR
Incidence
Proportion reflecting # of new cases of a disorder relative to total population at a given time
estimate of risk of developing disease at that time
Cumulative Incidence
(# new cases at period of time) / (total population at risk)
Incidence Rate
(# new cases at period of time) / (total person - time)
considered a more efficient measure to allow inclusion of all subjects
Incidence rate
only accounts for subjects available for entire study period
Cumulative Incidence
Exploratory epidemiologic study
assess relationship between exposure and disease status
establishes if association exists and its strength
Exploratory epidemiologic studies presented as:
case control studies
cohort studies
Relative risk
incidence of disease amongst exposed
/
incidence of disease among unexposed
