Epidemiology: Study Design Flashcards
If the results from a randomized control trial are able to be generalized to a broader population, the study is said to have (internal/external) validity.
External
is a strategy used in research to prevent subjects from knowing whether they are in a control group or a treatment group.
Masking
In randomization, individuals are first stratified into groups based on important characteristics, and then randomly assigned to groups within the strata.
Stratified
The current practice in randomized control trials is to evaluate the study based on the , regardless of what happened to the subjects after being randomly assigned to groups.
Intention to treat
When a randomized control trial is particularly concerned about the comparability of treatment groups in a few characteristics, randomization is employed.
Stratified
In a randomized control trial, a substance that is physically similar, but not equal in bioactivity, to the active agent being tested is called a ____________.
Placebo
In case control studies, the population that have a certain outcome, is called .
Cases
“Does Medication A have a different cure rate than Medication B?” is an example of a/an (one-sided/two-sided) study
Two-sided
To determine the true side effect profile of a treatment, the rate of side effects of a treatment should be compared to the rate of side effects due to a .
The of a study refers to how well a study can detect a difference between two treatments when a difference really does exist.
Power
In (planned/unplanned) crossover in a randomized control trial, there must be enough of a washout period after the first treatment protocol so that there is no overlap between treatments.
Planned
is a research strategy that masks both the subject and the observer from knowing which group- treatment or control- a subject is in.
Double blinding
The use of a can help to determine the real effects of a treatment as well as its side effects.
Placebo
In a (prospective/retrospective) cohort study, an investigator follows the subjects until the point at which a disease does or does not develop.
Prospective
Cohort studies allow for the measurement of (absolute/relative) risk of disease development in exposed individuals.
Relative risk
Randomized control trials most often measure the (efficacy/effectiveness) of an agent, or how well it works under ideal circumstances.
Efficacy
The five details needed before determining the right sample size are: .
current response rate, the estimated difference in response rates, whether the test is one- or two- tailed, the p- value, and power.
(Planned/Unplanned) crossover in a randomized control trial refers to a patient’s last minute decision to back out of the treatment group to which they were randomized.
Unplanned
The __________ control trial is referred to as the “golden standard” of any study design.
randomized
In a randomized control trial, refers to the masking of both the patients and the investigators of the study.
Double blinding
In a randomized control trial, the patients who receive the placebo are part of a (treatment/control) group.
Control
In (planned/unplanned) crossover in a randomized control trial, a patient is observed taking both a current and new treatment option.
Planned
In cohort studies, the selection of study groups (is/is not) random.
Is not
Ecological studies looking to measure prevalence and incidence in a certain geographical population are especially useful when the disease is (common/rare) .
Rare
Ecological studies (are/are not) designed to find causal relationships between variables.
Are not
A study is the comparison of the incidence of disease between an exposed group of individuals to a non-exposed group either retrospectively or prospectively.
Cohort
Ecological studies look at a(n) to figure out if there is a potential association between two variables.
Group population
A down-side to case-control studies is , where subjects overestimate or underestimate the exposure.
Recall bias
The (efficacy/effectiveness) of an agent is how well it works in real-life circumstances.
Effectiveness
Randomly selected people for a study (should/should not) be representative of the population being studied.
Should
Ecological studies compare the risk-modifying factors of health in a certain population determined by its to another different population.
Geography
When two independent drugs are introduced in a randomized control trial, the study variant is called _____________ design.
Factorial
The main purpose of randomization is to eliminate potential that are subconsciously introduced through investigator assignment.
Biases
One way to report the results of a randomized control trial is to calculate the ratio of risks between the two treatment groups, which is also known as the risk.
Relative risk
The is the probability that the summary of a dataset, such as a mean difference between two groups, would be the same as, or more extreme than, the number observed in the study.
P-value
A cohort study (can/cannot) be both retrospective and prospective in nature.
Can
Cohort studies are concerned with disease (incidence/prevalence) because a temporal relationship exists between exposure and disease.
Incidence
Ensuring compatibility between treatment groups (is/is not) the main purpose of randomization in randomized control trials.
Is not
Historical data is examined in (prospective/retrospective) cohort studies.
Retrospective
(Selection/Information) bias occurs in cohort studies when the choice of subjects within exposed or non-exposed groups relates to the outcome.
Selection
A p-value of 0.05 means that there’s a % probability to find the observed data in case the null hypothesis were true.
5%
A is an inert substance that appears to be the same as the active agent.
Placebo
(Selection/Information) bias is introduced to cohort studies when investigators subconsciously analyze data differently based on their preconceptions.
Information
(Selection/Information) ________ bias is introduced to cohort studies when the extent or quality of knowledge differs between the exposed and non-exposed groups.
Information
The (efficacy/effectiveness) of an agent is how well it works under ideal circumstances.
Efficacy
Randomization in a randomized control trial will theoretically (increase/decrease) the likelihood that the different groups will be comparable to one another in demographic characteristics.
Increase
Two different drugs can be included in a randomized control trial as long as their pharmacokinetics are (dependent/independent) of one another.
Independent
Case-control studies can also be used to explore many exposures associated with an outcome, which comes in handy for investigations.
Outbreak
If a randomized control trial was properly performed without any bias, it has (internal/external) validity.
Internal
“Does Medication A have a lower cure rate than Medication B?” is an example of a/an (one-sided/two sided) study.
One-sided
In case control studies, the population that doesn’t have a certain outcome, is called .
Controls
When the treatment groups in a randomized control trial are (large/small) , there is a greater chance that each group will be comparable to each in demographic characteristics.
Large
When group-level information is used to make assumptions about individuals, it’s called a/an __________.
Ecological fallacy
A (case-control/cohort) study aims to see if exposure affects the likelihood of a disease.
Cohort
To determine the true side effect profile of a treatment, the rate of side effects of a treatment should be compared to the rate of side effects due to a .
Placebo
Case-control studies are a type of study since they look at the past exposures of people.
Retrospective
Randomization of subjects (is/is not) necessary when the same patient undergoes both the control and treatment course.
Is not
