Exam 02 Flashcards
need to add vaccine info but otherwise complete
Three factors in the epidemiological triangle
Agent, Host, Environment
Agent types
Infectious agents
Chemical agents
Physical agents
Host characteristics
genetic susceptibility
immutable characteristics (age, sex)
acquired characteristics
lifestyle factors
Environment characteristics
Climate
Plant and animal life
Human population distribution
Socioeconomic factors
Working conditions
The 5 Ws of Epidemiology, separated into descriptive and analytic
DESCRIPTIVE:
- what is the outcome?
- who is affected
- where are they
- when do events occur
ANALYTIC:
- how does it occur
- why are some affected more than others
What is the difference between descriptive and analytic epidemiology
descriptive looks at the distribution of health outcomes
analytic looks at the determinants of outcomes
epidemic
occurrence of disease in a community or region in excess of normal expectancy
two key historical figures of epidemiology
Hippocrates: ecological model
John Snow: father of epidemiology
Proportion
type of ratio in which denominator includes the numerator. e.g. x amount of sick people / x total people
rates
measure of frequency of a health event in a defined population, in a specific period of time. rates usually expressed per 100k population per year
risk
probability that an event will occur within a specified period of time
prevalence
number of existing cases, expressed in a percent; proportion!
e.g. deaths d/t heart disease over total number of deaths
incidence
number of new cases over number of people at risk; usually expressed as x cases/100k pop at risk annually; RATE!
attack rate
proportion of people who are exposed to an agent and develop the disease
e.g. ill people after exposure/total exposed
mortality rate limitations
can provide info about fatal diseases or events, but not info about level of existing disease in population.
Mortality vs Morbidity
Mortality: rate of deaths
Morbidity: disease prevalence, can be harder to attain
Primary sources of epidemiology data
collected directly through interaction with community members, + OG info for specific epidemiologic studies; NCHS, NHDS
Secondary sources of epidemiology data
Collected through existing reports on the community, including routinely collected data. Includes census, vital statistics/records, CDC data, data collected for other purposes, etc
Annual population estimate number
estimate of population at midyear as the denominator for annual rates, since pop. changes during the course of a year
Reliability
repeatability or consistency of a measure
Validity
accuracy measuring what is intended.
Includes sensitivity and specificity
Sensitivity
test ID those with the condition (true positive)
Specificity
test ID those w/o condition (true negative)
Bioterrorism
intentional release/dissemination of biological agents
common agents: anthrax, smallpox, plague