Ch9 Flashcards
proportion
a type of ratio in which the denominator includes the numerator
incident rate
reflects the number of NEW cases developing in a population at risk during a specified time. It estimates the risk for developing the disease in the observed population within a specified time.
incident proportion
reflects the cumulative effect of the incidence rate over the time period.
prevalance proportion
The prevalence proportion measures existing disease in a population at a particular time; that is, the number of existing cases divided by the current population.
risk
risk is the probability that an event will occur within a specified period. It is distinguished from a HIGH-RISK POPULATION, those persons for whom a greater probability exists of the event occurring.
epidemic
rate of disease exceeds typical rate of spread
attack rate
The attack rate is a measure of morbidity, defined as the proportion of persons exposed to an agent who develop the disease. Attack rates are often specific to an exposure.
mortality
Mortality rates provide information about deaths and fatal diseases. Commonly used mortality rates include the crude mortality rate, age-specific rate, case-fatality rate, and the infant mortality rate
web of causality
The web of causality illustrates the complex interrelationships of numerous factors interacting to increase (or decrease) the risk of disease.
Recognizes the complex interrelationships of many factors interacting, sometimes in subtle ways, to increase or decrease the risk for disease
Relationships are sometimes mutual, with lines of causality going in both directions
sensistivity
Sensitivity: quantifies how accurately the test identifies those with the condition or trait; true positives
specificity
Specificity: indicates how accurately the test identifies those without the condition or trait ; true negatives
Define epidemiology
Epidemiology: the study of the distribution and factors that determine health-related states or events in a population, and the use of this information to control health problems
Discuss the steps in the epidemiologic process
Step 1 – Answer the “what” question – ex: what disease – cancer
Step 2 – Answer the “who, where, when” – the distribution
Example – men in Bryan, Texas in 2012
Step 3 – Answer the “why and how” question
Explain how nurses use epidemiology in community health practice
nurses look at health and at disease causation and investigate how to both prevent and treat illness
Nurses are involved in the surveillance and monitoring of disease trends and can identify patterns of disease in a group. Nurses in the community may be the first to notice a new illness or symptoms
a form of epidemiology that describes disease in terms of person, place, or time
For example: What is the disease? Who is affected? Where are these people? When do events occur?
Descriptive epidemiology:
looks at the etiology (origins or causes) of the disease and deals with determinants of health and disease
For example: How does it occur? Why are some people affected more than others?
Analytic epidemiology:
purpose of epidemiology
monitor the health of the population
identify determinants of health and disease in the communities
investigate and evaluate intervention to prevent disease and maintain health
first person to use the ideas that are now part of epidemiology
hippocrates was the first person to use the ideas that are now part of epidemiology
developed both germ theory and pasteurization
louis pasteur
developed antiseptic surgery
joseph lister
developed pure culture and identified the cusal organisms that cause TB, anthrax, and cholera disease
john snow ( father of epidemiology)
who is the father of epidemiolgy?
john snow
considered relationship between environmental conditions and recovery of soldiers during Crimean War. Able to decrease mortality rates by improving environmental conditions and adding nursing care
Florence Nightingale
rate
the basic measure in epidemiologic studies. A rate is a measure of the frequency of a health event in a defined population during a specified period
prevalence
of existing cases divided by current population; health dept needs to know this for planning purposes
agent
a factor that must be present or lacking in order for a disease or condition to develop
host
is a living species capable of being infected or affected by an agent
environment
is everything internal or external to a given host or agent and that is influenced and influences the host and/or agent
how precise is the measurement? the measurement’s consistency or repeatability
take BP 3 times and it is different each time
relaiability
the proportion of persons with a positive test who actually have the disease
Positive predictive value:
the proportion of persons with a negative test who are actually disease free
Negative predictive value:
in a screening test, how is validity measured?
using sensitivity and specificity
what is validity?
the accuracy of a test or measurement in measuring what it claims to measure.
A. Sources of data. Data for epidemiologic studies commonly come from three categories:
1. Routinely collected data such as census data, vital records, and surveillance data
2. Data collected for other purposes such as medical and insurance records
3. Original data collected for specific epidemiologic studies
B. Rate adjustment. Rates can be misleading when compared across different populations. Adjustments can be direct or indirect.
Basic methods in epidemiology
Descriptive versus analytic epidemiology:
Descriptive epidemiology describes the distribution of health outcomes according to person, place, and time—the who, where, and when of disease patterns.
Analytic epidemiology searches for the determinants of the patterns observed—the how and why.
