Study Guide Questions Exam 1 Flashcards
Definition of epidemiology
The study of the occurrence and distribution of health-related events, states, and processes in specified populations, including the study of the determinants influencing such processes and the application of this knowledge to control of relevant health problems
Definition of count
Refers to the number of cases of a disease or other health phenomenon being studied.
Definition of ratio
The value obtained by dividing one quantity by another. Rates and proportions are ratios.
Definition of proportion
A type of ratio in which the numerator is part of the denominator.
Rate definition
A type of ratio where the denominator involves a measure of time. The numerator consists of the frequency of a disease over a specified period, and the denominator is a unit size of the population.
Why are prevalence studies useful?
They describe the health burden of a population and in allocation of health resources.
Can be used by epidemiologists to estimate the frequency of an exposure in a population.
Population at risk definition
Those members of a population who are at risk for contracting a specific disease or adverse health outcome.
How does prevalence usually get reduced?
Death or cure
What can increase the prevalence?
New cases, or incidence
Prolongation of life with treatment, which does not completely cure the disease.
What are the two main branches of epidemiology?
Descriptive and analytic
Descriptive epidemiology definition
The study of the distribution of health states in populations by characteristics of person, place, and time.
What is the main purpose of descriptive epiemiology?
Looks for patterns between groups of people, over time or across geographical areas.
What is the main concern of analytic epidemiology?
The study of determinants
Definition of analytic epidemiology
The multi-disciplinary study of the determinants of health states in populations, on all levels from the molecular to the entire ecosystem, and including both the biological sphere and the broader social environment.
What are the four main purposes of epidemiology?
- Public health assessment
- Evaluating a health program, policy, or clinical service.
- Finding causes of a disease.
- Completing the clinical picture of a dz
Definition of duration
The average length of time that people are ill with a dz
Begins at illness and ends at recovery or death
Limitations of counts
Gives very limited information
You cannot compare two populations using counts.
What can decrease the prevalence?
Decreased incidence
Improved cure rate
Increased death rate
What increases incidence?
Increased risk
What decreases incidence?
Decreased risk
How is incidence useful?
Helps in research of etiology/causality of dz
Estimates the risk of developing a dz
Used to estimate the effects of exposure to a hypothesized factor of interest
How are prevalence and incidence related to each other?
Prevalence = incidence x duration
Definition of crude rates
Summary rates based on the actual number of events in a population over a given time period.
Specific rates definition
A type of rate based on a particular subgroup of population defined, for example, in terms of race, age, or sex, or they may refer to the entire population but be specific for some single cause of death or illness.
Cause-specific rate definition
A rate that specifies events, such as deaths according to their cause.
What is a disadvantage of specific rates?
The difficulty of visualizing the big picture of these situations.
Definition of adjusted rates
Summary measures of the rate of morbidity or mortality in a population in which statistical procedures have been applied to remove the effect of differences in composition of the various populations.