NR-503 Epidemiology Final Question and
Answer | 100% Guaranteed A+
1. One must use care in interpreting occupational differences in morbidity and mortality
because:
A. good health status may be a factor for selection into a job.
B. occupations involving physical activity tend to cause heart attacks among older
workers.
C. occupational stress, even in extreme situations, is difficult to quantify.
D. A, B, and C -✓✓A. good health status may be a factor for selection into a job.
2. Asbestos exposure has been associated with: -✓✓D. asbestosis, malignant
mesothelioma, and lung cancer
3. A sentinel health event refers to: -✓✓a case of unnecessary workplace disease that
serves as a warning signal.
4. Exposure to electric and magnetic fields has been linked to: -✓✓childhood leukemia
risk
5. It has been suggested that occupational exposure to benzene in the petroleum
industry increases the risk of developing leukemia. The levels of benzene to which
workers in this industry have been exposed were high from 1940 to 1970, but since
1970 have been significantly reduced.
What kind of study design, using petroleum workers, would provide the most useful
information on whether benzene affects incidence rates of leukemia in this industry?
You may assume that records of individual worker assignments to jobs involving
benzene exposure have been maintained by the industry. -✓✓Retrospective cohort
6. Which of the following is the leading source of radiation? -✓✓Radon
7.The healthy worker effect -✓✓Healthy persons are more likely to gain employment
than unhealthy persons.
8.Synergism -✓✓A situation in which the combined effect of several exposures is
greater than the sum of the individual effects
9.Threshold -✓✓The lowest dose at which a particular response may occur
10.Latency -✓✓The time period between initial exposure and a measurable response
, 11.The population etiologic fraction is a measure of the proportion of the disease rate in
a population attributable to the exposure of interest. This measure of effect is influenced
by: -✓✓A & C
(The relative risk of the disease is exposed individuals versus unexposed & the
prevalence of the exposure in the population)
12.If it is accepted that an observed association is a casual one, an estimate of the
impact that a successful preventative program might have, can be derived from: -
✓✓attributable risk
When assessing a positive relationship between alcohol consumption and oral cancer
using a case-control study, increasing the sample size of the study will result in which of
the following? -✓✓None of the above
An attributable-risk percent of 80% was calculated for the association between smoking
and lung cancer death. Which of the following provides the best interpretation of this
statistic?
. -✓✓Of those dying of lung cancer who smoke, 80% of those deaths are contributed to
their smoking, assuming a casual association exists
Several studies have found that approximately 85% of cases of lung cancer are due to
cigarette smoking. This measure is an example of: -✓✓Attributable risk
Assuming that the sample table is for a cohort study, define the population risk
difference or population attributable risk: -✓✓(A+C/A+B+C+D)-(C/C+D)
Selection bias is most likely to occur in: -✓✓Both retrospective cohort and case control
studies
Recall bias is most likely to occur in: -✓✓Case control studies
In a study to determine the incidence of a chronic disease, 150 people were examined
at the end of a three-year period. Twelve cases were found, giving a cumulative risk of
8%. Fifty other members of the initial cohort could not be examined; 20 of these 50
could not be examined because they died. Which source of bias may have affected the
study? -✓✓Selection bias; survival bias
You are investigating the role of physical activity in heart disease and suggest that
physical activity protects against having a heart attack. While presenting these data to
your colleagues, someone asks if you have thought about confounders such as factor
X. This factor X could have confounded your interpretation of data if it: -✓✓Is a factor
associated with physical activity and heart disease
Answer | 100% Guaranteed A+
1. One must use care in interpreting occupational differences in morbidity and mortality
because:
A. good health status may be a factor for selection into a job.
B. occupations involving physical activity tend to cause heart attacks among older
workers.
C. occupational stress, even in extreme situations, is difficult to quantify.
D. A, B, and C -✓✓A. good health status may be a factor for selection into a job.
2. Asbestos exposure has been associated with: -✓✓D. asbestosis, malignant
mesothelioma, and lung cancer
3. A sentinel health event refers to: -✓✓a case of unnecessary workplace disease that
serves as a warning signal.
4. Exposure to electric and magnetic fields has been linked to: -✓✓childhood leukemia
risk
5. It has been suggested that occupational exposure to benzene in the petroleum
industry increases the risk of developing leukemia. The levels of benzene to which
workers in this industry have been exposed were high from 1940 to 1970, but since
1970 have been significantly reduced.
What kind of study design, using petroleum workers, would provide the most useful
information on whether benzene affects incidence rates of leukemia in this industry?
You may assume that records of individual worker assignments to jobs involving
benzene exposure have been maintained by the industry. -✓✓Retrospective cohort
6. Which of the following is the leading source of radiation? -✓✓Radon
7.The healthy worker effect -✓✓Healthy persons are more likely to gain employment
than unhealthy persons.
8.Synergism -✓✓A situation in which the combined effect of several exposures is
greater than the sum of the individual effects
9.Threshold -✓✓The lowest dose at which a particular response may occur
10.Latency -✓✓The time period between initial exposure and a measurable response
, 11.The population etiologic fraction is a measure of the proportion of the disease rate in
a population attributable to the exposure of interest. This measure of effect is influenced
by: -✓✓A & C
(The relative risk of the disease is exposed individuals versus unexposed & the
prevalence of the exposure in the population)
12.If it is accepted that an observed association is a casual one, an estimate of the
impact that a successful preventative program might have, can be derived from: -
✓✓attributable risk
When assessing a positive relationship between alcohol consumption and oral cancer
using a case-control study, increasing the sample size of the study will result in which of
the following? -✓✓None of the above
An attributable-risk percent of 80% was calculated for the association between smoking
and lung cancer death. Which of the following provides the best interpretation of this
statistic?
. -✓✓Of those dying of lung cancer who smoke, 80% of those deaths are contributed to
their smoking, assuming a casual association exists
Several studies have found that approximately 85% of cases of lung cancer are due to
cigarette smoking. This measure is an example of: -✓✓Attributable risk
Assuming that the sample table is for a cohort study, define the population risk
difference or population attributable risk: -✓✓(A+C/A+B+C+D)-(C/C+D)
Selection bias is most likely to occur in: -✓✓Both retrospective cohort and case control
studies
Recall bias is most likely to occur in: -✓✓Case control studies
In a study to determine the incidence of a chronic disease, 150 people were examined
at the end of a three-year period. Twelve cases were found, giving a cumulative risk of
8%. Fifty other members of the initial cohort could not be examined; 20 of these 50
could not be examined because they died. Which source of bias may have affected the
study? -✓✓Selection bias; survival bias
You are investigating the role of physical activity in heart disease and suggest that
physical activity protects against having a heart attack. While presenting these data to
your colleagues, someone asks if you have thought about confounders such as factor
X. This factor X could have confounded your interpretation of data if it: -✓✓Is a factor
associated with physical activity and heart disease
