Epidemiological Terms and Measures Flashcards
Lecture Objectives
discuss the practical importance of epidemiology, define descriptive and analytic epidemiology, identify the measures of disease frequency and measures of association, review the distributions of key forms of visual impairment in the US, differentiate between levels of disease in a population
T/F disease is evenly distributed in the population
false
Epidemiology
the study of the distribution of health-related states or events in specified populations and the application of this study to control health problems
What does epidemiology help us figure out?
who is at risk and why
Study
observing, recording, experimenting
Distribution
who, when, where
Determinants
why, how
health-related states
moves beyond the study of diseases
What is descriptive epidemiology?
pattern recognition; who, when, where
What does descriptive epidemiology generate?
measures of disease frequency
Rate
counting health events over time
Risk
likelihood of developing a disease
T/F descriptive epidemiology can be used to test hypotheses
false; can only generate hypotheses not test because there is no comparison group
What are general measures of disease frequency?
incidence rate, cumulative incidence aka cumulative risk, prevalence rate
What is the most fundamental measure of disease incidence?
incidence rate
What is incidence rate?
number of new cases per person-time of observation
What is person-time?
the amount of at-risk time each person contributes to the rate
What is the incidence rate equation?
new cases/ (person-time at risk)
What is cumulative incidence/risk?
risk of acquiring the disease within a defined period of time
What is the cumulative incidence/risk equation?
new cases/ total population at risk
T/F the longer the time period, the higher the cumulative incidence
true
T/F cumulative incidence/risk is given as a percentage
true
What is prevalence rate?
proportion of total cases in a population at one point in time
What is the prevalence rate equation?
P= incidence rate x average duration of disease
What is prevalence rate used for?
can be used for administration, planning, some research
If incidence rate goes up or survival time is long, prevalence is
high