Regis NU-713 Final Exam Questions And Answers
Verified 100% Correct
What is confounding? - ANSWER In a study of
whether factor A is a cause of disease B, we say that
a third factor, factor X, is a confounder if the following
are true:
1. Factor X is a known risk factor for disease B.
2. Factor X is associated with factor A, but is not a result of factor A.
Strategies/methods used to prevent, avoid or minimize confounding - ANSWER
individual matching, group matching, Stratification & adjustments (all of the above)
If a relationship is causal, ________ types of causal relationships are possible -
ANSWER 4
Koch's Postulates - ANSWER 3
In many studies examining the association between estrogens and endometrial cancer
of the uterus, a one-sided significance test was used. The underlying assumption
justifying a one-sided rather than a two-sided test is: - ANSWER The expectation
before doing the study was that estrogens cause endometrial cancer of the uterus
Assumptions for a one-sided test - ANSWER interested in one
direction—
improvement
Assumptions for a two-sided test - ANSWER as long as the difference
could go in either direction
Of 2,872 persons receiving radiation treatment in childhood because of an enlarged
thymus, thyroid cancer developed in 24 and a benign thyroid tumor developed in 52.
The comparison group consisted of 5055 children who received no such treatment
(brothers and sisters of the children who had received radiation treatment). During the
follow-up, none of the comparison group developed thyroid cancer, but benign thyroid
tumors developed in 6. The calculated relative risk for benign thyroid tumors is
________ - ANSWER 15.3
The usual first step in conducting new studies is to use a ________ design to explore a
relationship - ANSWER case-control study
, Selection Response Bias - ANSWER A bias is introduced by the selection of individuals
or groups in a way that one given group is more likely to get selected than another.
Population Attributable Risk (PAR) - ANSWER estimates excess rate of disease in the
total study population of exposed and non exposed individuals and helps determine
which exposures have the most relevance to the health of the community
robustness - ANSWER extent to which a particular hypothesis-testing procedure is
reasonably accurate even when its assumptions are violated
Causal Inference Ratio - ANSWER the process of drawing a conclusion about a causal
connection based on the conditions of the occurrence of an effect.
All of the following are important criteria when making causal inferences except: -
ANSWER predictive value
The purpose of a double blind or double masked study is to: - ANSWER Avoid
observer and subject bias
validity - ANSWER the ability to distinguish who has the disease and who does not has
the disease
Power - ANSWER how good our study is at correctly
identifying a difference between the therapies
if in reality they are different
The major purpose of random assignment in a clinical trial is to: - ANSWER Reduce
selection bias in the allocation of treatment
odds ratio - ANSWER The likelihood of a disease among individuals exposed to a risk
factor compared to those who have not been exposed
There are ________ guidelines used to determine whether an observed association is
causal. - ANSWER 3
Relative Risk (RR) - ANSWER The ratio of the incidence rate of a disease or health
outcome in an exposed group to the incidence rate of the disease or condition in a
nonexposed group.
180 patients were treated for disease X from 2007 to 2009. Their progress was followed
to 2010. Treatment results are given in the table. No patients were lost to follow
up.What is the computed probability of surviving for three years? - ANSWER 54.8%
Verified 100% Correct
What is confounding? - ANSWER In a study of
whether factor A is a cause of disease B, we say that
a third factor, factor X, is a confounder if the following
are true:
1. Factor X is a known risk factor for disease B.
2. Factor X is associated with factor A, but is not a result of factor A.
Strategies/methods used to prevent, avoid or minimize confounding - ANSWER
individual matching, group matching, Stratification & adjustments (all of the above)
If a relationship is causal, ________ types of causal relationships are possible -
ANSWER 4
Koch's Postulates - ANSWER 3
In many studies examining the association between estrogens and endometrial cancer
of the uterus, a one-sided significance test was used. The underlying assumption
justifying a one-sided rather than a two-sided test is: - ANSWER The expectation
before doing the study was that estrogens cause endometrial cancer of the uterus
Assumptions for a one-sided test - ANSWER interested in one
direction—
improvement
Assumptions for a two-sided test - ANSWER as long as the difference
could go in either direction
Of 2,872 persons receiving radiation treatment in childhood because of an enlarged
thymus, thyroid cancer developed in 24 and a benign thyroid tumor developed in 52.
The comparison group consisted of 5055 children who received no such treatment
(brothers and sisters of the children who had received radiation treatment). During the
follow-up, none of the comparison group developed thyroid cancer, but benign thyroid
tumors developed in 6. The calculated relative risk for benign thyroid tumors is
________ - ANSWER 15.3
The usual first step in conducting new studies is to use a ________ design to explore a
relationship - ANSWER case-control study
, Selection Response Bias - ANSWER A bias is introduced by the selection of individuals
or groups in a way that one given group is more likely to get selected than another.
Population Attributable Risk (PAR) - ANSWER estimates excess rate of disease in the
total study population of exposed and non exposed individuals and helps determine
which exposures have the most relevance to the health of the community
robustness - ANSWER extent to which a particular hypothesis-testing procedure is
reasonably accurate even when its assumptions are violated
Causal Inference Ratio - ANSWER the process of drawing a conclusion about a causal
connection based on the conditions of the occurrence of an effect.
All of the following are important criteria when making causal inferences except: -
ANSWER predictive value
The purpose of a double blind or double masked study is to: - ANSWER Avoid
observer and subject bias
validity - ANSWER the ability to distinguish who has the disease and who does not has
the disease
Power - ANSWER how good our study is at correctly
identifying a difference between the therapies
if in reality they are different
The major purpose of random assignment in a clinical trial is to: - ANSWER Reduce
selection bias in the allocation of treatment
odds ratio - ANSWER The likelihood of a disease among individuals exposed to a risk
factor compared to those who have not been exposed
There are ________ guidelines used to determine whether an observed association is
causal. - ANSWER 3
Relative Risk (RR) - ANSWER The ratio of the incidence rate of a disease or health
outcome in an exposed group to the incidence rate of the disease or condition in a
nonexposed group.
180 patients were treated for disease X from 2007 to 2009. Their progress was followed
to 2010. Treatment results are given in the table. No patients were lost to follow
up.What is the computed probability of surviving for three years? - ANSWER 54.8%
