Applied Epidemiology and Biostatistics
Midterm 522 Rush
What is epidemiology? - ANS-The study of the distribution and determinants of
heath-related states or events in specified populations, and the application of this
knowledge to the control of health problems
Distribution - ANS-Refers to person, place, and time
Determinants - ANS-Physical, biological, social, cultural,
economic and behavioral factors that influence health
Health-Related States or Events - ANS-Includes wellness,
illness, disease, injury, impairments, and disability
Specified Populations - ANS-The characteristics of who is
healthy, who is at risk for the disease, and who acquires the disease
Control of Health Problems - ANS-The goal of epidemiology is to identify factors
associated with the development of disease as well as factors that prevent illness
Epidemiology focuses on _______________ - ANS-*Populations* & *Population Health*
Not focused on providing direct care to individuals
6 Core Epidemiological Functions - ANS-Surveillance
Field Investigations
Analytical Studies
Evaluation
*Linkages*
Policy
Epidemiology is a ____________ science - ANS-Quantitative
Epidemiological Study - ANS-Refers to systematic surveillance, observation,
experimentation... use of a scientific approach
Two Major Branches of Epidemiology - ANS-Descriptive & Analytic Epidemiology
,Descriptive Epidemiology - ANS-*distribution, frequency, and pattern* of health-related
states and events (the who, where, when/person, place, time
Analytic Epidemiology - ANS-*determinants* of health-related states and events (the
why/causes
Mission of CDC - ANS-Protect the health of the nation
Variable - ANS-Any characteristic that can vary; the thing being measured or observed
T/F: An operational definition defines how a variable will be measured, and includes the
equipment and procedures that are used in the measurement. - ANS-True
The conceptual definition of a variable:
a. Explains what the variable means.
b. Specifies how a variable should be measured.
c. Describes the standards for measuring a variable.
d. Specifies the precision of the measurements. - ANS-a. Explains what the variable
means
Conceptual Definitions - ANS-*Defines the variable*; dictionary definition
Operational Definitions - ANS-Specifies how variable is measured; describes
*operations used to obtain measurement*
The dependent variable is:
a. The intervention being studied.
b. The outcome variable.
c. The variable manipulated by the researcher.
d. A characteristic of the person being studied. - ANS-b. The outcome variable
Independent Variable - ANS-Manipulated in a study to see if it affects the outcome(s)
being studied
Intervention/treatment
Usually only 1
, Effects/causes the outcome of interest
T/F: A study can have more than one dependent (outcome) variable. - ANS-True
Dependent Variable - ANS-*Outcome*/response variable(s)
Can be more than 1
Caused by independent variable
T/F: The reliability of a weight measurement obtained with an electronic scale refers to
the accuracy of the measurement. - ANS-False
Testing a new piece of equipment to ensure that the equipment consistently provides
that same measurement when the same variable is measured multiple times is an
example of
a. Validity
b. Reliability
c. Accuracy
d. All of the above - ANS-b. Reliability
Reliability - ANS-Refers to the *repeatability or reproducibility* of the measurements
Validity - ANS-Is about the *accuracy* of data
Addresses whether the measurement truly measures the variable of interest
Two types of Categorical Data - ANS-*Nominal* (named categories) and *Ordinal*
(ranked categories)
Nominal Data - ANS-Data classified into categories with names
ex. race, gender, ethnicity, relationship status, disease status, consent, y/n, blood type
Ordinal Data - ANS-Categories that have an order/rank to them
ex. grades A,B,C,D,F; pain level, education level, cancer stages