PUBH 6003 Final Exam-updated
2024/2025 with questions and all
correct answers
Epidemiology definitions - CORRECT ANSWER- Study of how diseases are distributed
in populations and the factors that influence or determine these distributions
- study of distribution and determinants of health-related states or events in specified
populations and the application of this study to control of health problems
- basic science of public health
Fixed population - CORRECT ANSWER members can only "leave" population through
death. No one new enters the population during the study period.
dynamic population - CORRECT ANSWER new members can join via birth, migration,
or an event that makes them a member. Subjects may come and go from the population
during the study period.
Goals of epidemiology - CORRECT ANSWER- identify etiology and relevant risk factors
of disease
- determine extent of disease in community
- study natural history and progression of disease
- evaluate preventive and therapeutic measures and modes of delivery
Epi and clinical medicine - CORRECT ANSWER provides evidence for evidence-based
medicine
- diagnosis, prognosis, and selection of therapy or prophylaxis
statistics - CORRECT ANSWER group measures
descriptive epi objectives - CORRECT ANSWER person, place and time
Frequency - CORRECT ANSWER simple count of events, absolute measure
Ratio - CORRECT ANSWER comparison of 2 quantities that can be reduced to a
quotient
, (A/B, A:B, A to B, A per B)
ex. in a class: 25 males, 75 females...... females to males is 75:25, 3:1, or 3
used for comparisons that are not proportions or rates
Proportions - CORRECT ANSWERa ratio of a part to the whole, a subset to entire set
(Always same unit of measure)
ex. proportion female 75/100, 75%
More on proportions - CORRECT ANSWER- can never have a numerator greater than
the denominator
- always a proper fraction
- unit-less (they cancel out)
- % are proportions
- cases must be from the same population
Rates - CORRECT ANSWERratio of two different measurements
Ex. beats per second, mph, taxes/$, new cases per population
more on rates - CORRECT ANSWER- usually involve time, ALWAYS do in epi
- can be a % if same units
- may be expressed in easier to understand units ( PER 100,000)
- PER
prevalence - CORRECT ANSWERmeasure of disease present at one point in time or
one period in time
- can be a count (prevalent cases)
- MAINLY is a proportion (prevalence)
- measure of disease burden
- sometimes called a rate, but is not
- not indicative of RISK
(not the probability of an event happening, is a proportion of events in a population)
Incidence - CORRECT ANSWERmeasure of new cases or events
- can be a count (incidence cases)
- can be proportion of at risk population over some time period (incidence)
- incidence of disease = rate of disease
- IS indicative of risk
assumptions of cumulative incidence - CORRECT ANSWER- researcher knows when
each participant becomes a case
- researcher knows if each outcome free ppt remains outcome free
- LTFU must be discarded or a shorter time period must be used
- person time can be used in denominator of the rate and avoid the assumptions
needed for cumulative incidence
2024/2025 with questions and all
correct answers
Epidemiology definitions - CORRECT ANSWER- Study of how diseases are distributed
in populations and the factors that influence or determine these distributions
- study of distribution and determinants of health-related states or events in specified
populations and the application of this study to control of health problems
- basic science of public health
Fixed population - CORRECT ANSWER members can only "leave" population through
death. No one new enters the population during the study period.
dynamic population - CORRECT ANSWER new members can join via birth, migration,
or an event that makes them a member. Subjects may come and go from the population
during the study period.
Goals of epidemiology - CORRECT ANSWER- identify etiology and relevant risk factors
of disease
- determine extent of disease in community
- study natural history and progression of disease
- evaluate preventive and therapeutic measures and modes of delivery
Epi and clinical medicine - CORRECT ANSWER provides evidence for evidence-based
medicine
- diagnosis, prognosis, and selection of therapy or prophylaxis
statistics - CORRECT ANSWER group measures
descriptive epi objectives - CORRECT ANSWER person, place and time
Frequency - CORRECT ANSWER simple count of events, absolute measure
Ratio - CORRECT ANSWER comparison of 2 quantities that can be reduced to a
quotient
, (A/B, A:B, A to B, A per B)
ex. in a class: 25 males, 75 females...... females to males is 75:25, 3:1, or 3
used for comparisons that are not proportions or rates
Proportions - CORRECT ANSWERa ratio of a part to the whole, a subset to entire set
(Always same unit of measure)
ex. proportion female 75/100, 75%
More on proportions - CORRECT ANSWER- can never have a numerator greater than
the denominator
- always a proper fraction
- unit-less (they cancel out)
- % are proportions
- cases must be from the same population
Rates - CORRECT ANSWERratio of two different measurements
Ex. beats per second, mph, taxes/$, new cases per population
more on rates - CORRECT ANSWER- usually involve time, ALWAYS do in epi
- can be a % if same units
- may be expressed in easier to understand units ( PER 100,000)
- PER
prevalence - CORRECT ANSWERmeasure of disease present at one point in time or
one period in time
- can be a count (prevalent cases)
- MAINLY is a proportion (prevalence)
- measure of disease burden
- sometimes called a rate, but is not
- not indicative of RISK
(not the probability of an event happening, is a proportion of events in a population)
Incidence - CORRECT ANSWERmeasure of new cases or events
- can be a count (incidence cases)
- can be proportion of at risk population over some time period (incidence)
- incidence of disease = rate of disease
- IS indicative of risk
assumptions of cumulative incidence - CORRECT ANSWER- researcher knows when
each participant becomes a case
- researcher knows if each outcome free ppt remains outcome free
- LTFU must be discarded or a shorter time period must be used
- person time can be used in denominator of the rate and avoid the assumptions
needed for cumulative incidence
