Biostatistics in Epidemiological Research Exam Questions and Answers.
epidemiology - Answers the study of the distribution and determinants of disease frequency in human
populations
prevalent cases - Answers number of persons who have a disease at a specific point in time; this is
considered numerator data
prevalence - Answers the proportion of the population with a particular disease at a specific point in
time
pre-test probability - Answers the chance that any one person selected at random from a population will
have the disease of interest
prevalence - Answers another term for pre-test probability
incident disease events - Answers occurrences of a disease during a specified observation period; one
person may experience more than one such disease event during the time period (e.g., 2 colds in one
year).
incident cases - Answers the number of persons who develop a disease during a specified observation
period; each person is counted only once, regardless of the number of disease events
cumulative incidence - Answers the proportion of new cases observed in the population at risk during
the specified observation period; estimates the probability that an individual chosen at random from the
population will develop the disease during the specified time period
incidence rate - Answers the rate at which new cases develop in a population, relative to the size of the
population; the number of new cases per person-(time at risk)
incidence rate - Answers other words for this term include hazard and incidence density
incidence - Answers a measure of new cases of disease which occur in a population at risk during a
specified period of observation
mortality - Answers the incidence of death in a population during a specified period of time
cumulative incidence - Answers the most common way to evaluate risk
cumulative incidence - Answers evaluating this measure of disease frequency requires a closed
population
case fatality - Answers the proportion of persons with a particular disease who die
proportionate mortality - Answers the proportion of all deaths due to a particular disease
case-control study - Answers a study type designed to address problems of diseases with long latency
periods
, case-control study - Answers The basic design of this type of study is:
1. Assemble a group of individuals with a particular disease along with a comparable group of subjects
free of the disease.
2. Obtain information about previous medical history and health habits concerning the risk factor(s) of
interest.
3. Estimate the odds ratio for the association between exposure to the risk factor and development of
the disease
case-control study - Answers the study type that is most prone to bias and confounding
cohort study - Answers a study type designed to obtain accurate exposure history before (often many
years before) the outcome event or the disease has occurred.
cohort study - Answers The basic design of this study type is:
1. Assemble a group of individuals who are free of the disease of interest.
2. Classify each individual with respect to exposure status.
3. Follow and determine the development of disease.
4. Calculate the relative risk for the association between exposure to the risk factor and development of
the disease.
randomized control trial (RCT) - Answers this study type is considered the "Gold Standard" or "Cadillac"
of all study types
randomized control trial (RCT) - Answers this study type allows investigators the best opportunity to
directly measure the effect of exposures or treatments on the disease or outcome of interest
randomized control trial (RCT) - Answers The basic design of this study type is:
1. Select individuals with disease of interest.
2. Randomly assign each individual to an intervention or treatment.
3. Follow and observe the outcome of treatment.
4. Calculate the relative risk for the association between the assigned treatment and the observed
outcome.
clinical epidemiology - Answers the study of variation in the outcome of disease and of the reasons for
that variation
epidemiology - Answers the study of the distribution and determinants of disease frequency in human
populations
prevalent cases - Answers number of persons who have a disease at a specific point in time; this is
considered numerator data
prevalence - Answers the proportion of the population with a particular disease at a specific point in
time
pre-test probability - Answers the chance that any one person selected at random from a population will
have the disease of interest
prevalence - Answers another term for pre-test probability
incident disease events - Answers occurrences of a disease during a specified observation period; one
person may experience more than one such disease event during the time period (e.g., 2 colds in one
year).
incident cases - Answers the number of persons who develop a disease during a specified observation
period; each person is counted only once, regardless of the number of disease events
cumulative incidence - Answers the proportion of new cases observed in the population at risk during
the specified observation period; estimates the probability that an individual chosen at random from the
population will develop the disease during the specified time period
incidence rate - Answers the rate at which new cases develop in a population, relative to the size of the
population; the number of new cases per person-(time at risk)
incidence rate - Answers other words for this term include hazard and incidence density
incidence - Answers a measure of new cases of disease which occur in a population at risk during a
specified period of observation
mortality - Answers the incidence of death in a population during a specified period of time
cumulative incidence - Answers the most common way to evaluate risk
cumulative incidence - Answers evaluating this measure of disease frequency requires a closed
population
case fatality - Answers the proportion of persons with a particular disease who die
proportionate mortality - Answers the proportion of all deaths due to a particular disease
case-control study - Answers a study type designed to address problems of diseases with long latency
periods
, case-control study - Answers The basic design of this type of study is:
1. Assemble a group of individuals with a particular disease along with a comparable group of subjects
free of the disease.
2. Obtain information about previous medical history and health habits concerning the risk factor(s) of
interest.
3. Estimate the odds ratio for the association between exposure to the risk factor and development of
the disease
case-control study - Answers the study type that is most prone to bias and confounding
cohort study - Answers a study type designed to obtain accurate exposure history before (often many
years before) the outcome event or the disease has occurred.
cohort study - Answers The basic design of this study type is:
1. Assemble a group of individuals who are free of the disease of interest.
2. Classify each individual with respect to exposure status.
3. Follow and determine the development of disease.
4. Calculate the relative risk for the association between exposure to the risk factor and development of
the disease.
randomized control trial (RCT) - Answers this study type is considered the "Gold Standard" or "Cadillac"
of all study types
randomized control trial (RCT) - Answers this study type allows investigators the best opportunity to
directly measure the effect of exposures or treatments on the disease or outcome of interest
randomized control trial (RCT) - Answers The basic design of this study type is:
1. Select individuals with disease of interest.
2. Randomly assign each individual to an intervention or treatment.
3. Follow and observe the outcome of treatment.
4. Calculate the relative risk for the association between the assigned treatment and the observed
outcome.
clinical epidemiology - Answers the study of variation in the outcome of disease and of the reasons for
that variation
