EPIB Exam 2 Practice Questions with Complete
Solutions
Which of the following studies does NOT use individuals as the unit of analysis? - Correct Answer
ecological study
NAME THAT STUDY: A community assesses a random sample of its residents by telephone
questionnaire. Participants are asked to report their height, weight and the presence of any current
health conditions (e.g., hypertension, diabetes). Findings indicate that obesity is strongly associated
with diagnosed diabetes. - Correct Answer cross-sectional
T/F: Loss to follow up can be a problem in cohort studies but not experimental studies. - Correct
Answer false
Name that study design: In 1995 researchers obtained the personnel and health records from two
large insulation factories in the southeastern U.S. The records showed that between 1951 and 1955
there were 825 workers employed at Factory A, and 700 workers employed at Factory B.
Between1951-1994 there were 26 deaths from lung cancer among the workers from Factory A,
where asbestos was used in production. During the same time period there were only six lung cancer
deaths, among the workers from Factory B, where asbestos was not used in production. The
investigators hypothesized that exposure to asbestos was associated with an increased risk of lung
cancer. - Correct Answer retrospective cohort study
Name that study design: To see if hypnosis could reduce chronic pain, investigators randomly
assigned 120 volunteers with osteoarthritis to either hypnosis therapy or standard treatment. Pain
levels were checked among the subjects every three months during the 12-month study using
validated pain measures. Those assigned to the hypnosis group reported reduced pain compared to
those in the standard treatment group after three and six months, but not after nine and 12 months
of follow up. - Correct Answer randomized controlled trial
name that study design: A study was undertaken to test the hypothesis that chewing tobacco
increases the risk of stomach cancer. Detailed historical data on chewing tobacco use was collected
from 400 subjects with newly diagnosed stomach cancer and 400 subjects without stomach cancer.
Participants without stomach cancer were matched to those with cancer on background
characteristics such as age, race/ethnicity and gender. The results revealed that chewing tobacco was
not a significant risk factor for stomach cancer. - Correct Answer case-control study
name that study design: An epidemiologist tested the hypothesis that vitamin D (i.e., the "sunshine"
vitamin) is associated with reduced levels of ovarian cancer using data from 12 geographic regions in
Sweden. The association was measured using the average annual number of days of sunlight and the
rate of ovarian cancer in each region. The findings indicated that the regions with the highest
, average days of sunlight per year had significantly lower rates of ovarian cancer than those regions
with the fewest average days of sunlight per year. The epidemiologist reported her findings at the
Scandinavian Conference on Cancer - Correct Answer ecological study
name that study design: Study investigators invited all male physicians in the UK to fill out
questionnaires regarding their health status and their smoking status. They then focused on the
healthy physicians who were willing to participate and mailed follow-up questionnaires to them
every 2 years. Using death certificate data the researchers noted the cause of death for any subjects
who became ill and died. The study continued for 50 years - Correct Answer prospective cohort study
Which of the following is NOT a purpose of randomization? - Correct Answer To match on exposure
purposes of randomization - Correct Answer To ensure that treatment is assigned in an unbiased
fashion
To ensure comparability between treatment groups
To minimize confounding
Which of the following is NOT an advantage of randomization? - Correct Answer It can minimize loss
to follow-up
advantages of randomization - Correct Answer It can control for known confounders
It can control for unknown confounders
It can ensure comparability between study groups
The Behavioral Risk Factor Surveillance System (BRFSS) collects information on health risks and
behaviors annually, through a random digit-dialing system every year.
What kind of study design is this? - Correct Answer Cross-Sectional Study
The Nurses' Health Study is a prospective cohort study that follows female nurses, aged 25-42. Which
of the following techniques does this study use to minimize confounding? - Correct Answer
Restriction
Solutions
Which of the following studies does NOT use individuals as the unit of analysis? - Correct Answer
ecological study
NAME THAT STUDY: A community assesses a random sample of its residents by telephone
questionnaire. Participants are asked to report their height, weight and the presence of any current
health conditions (e.g., hypertension, diabetes). Findings indicate that obesity is strongly associated
with diagnosed diabetes. - Correct Answer cross-sectional
T/F: Loss to follow up can be a problem in cohort studies but not experimental studies. - Correct
Answer false
Name that study design: In 1995 researchers obtained the personnel and health records from two
large insulation factories in the southeastern U.S. The records showed that between 1951 and 1955
there were 825 workers employed at Factory A, and 700 workers employed at Factory B.
Between1951-1994 there were 26 deaths from lung cancer among the workers from Factory A,
where asbestos was used in production. During the same time period there were only six lung cancer
deaths, among the workers from Factory B, where asbestos was not used in production. The
investigators hypothesized that exposure to asbestos was associated with an increased risk of lung
cancer. - Correct Answer retrospective cohort study
Name that study design: To see if hypnosis could reduce chronic pain, investigators randomly
assigned 120 volunteers with osteoarthritis to either hypnosis therapy or standard treatment. Pain
levels were checked among the subjects every three months during the 12-month study using
validated pain measures. Those assigned to the hypnosis group reported reduced pain compared to
those in the standard treatment group after three and six months, but not after nine and 12 months
of follow up. - Correct Answer randomized controlled trial
name that study design: A study was undertaken to test the hypothesis that chewing tobacco
increases the risk of stomach cancer. Detailed historical data on chewing tobacco use was collected
from 400 subjects with newly diagnosed stomach cancer and 400 subjects without stomach cancer.
Participants without stomach cancer were matched to those with cancer on background
characteristics such as age, race/ethnicity and gender. The results revealed that chewing tobacco was
not a significant risk factor for stomach cancer. - Correct Answer case-control study
name that study design: An epidemiologist tested the hypothesis that vitamin D (i.e., the "sunshine"
vitamin) is associated with reduced levels of ovarian cancer using data from 12 geographic regions in
Sweden. The association was measured using the average annual number of days of sunlight and the
rate of ovarian cancer in each region. The findings indicated that the regions with the highest
, average days of sunlight per year had significantly lower rates of ovarian cancer than those regions
with the fewest average days of sunlight per year. The epidemiologist reported her findings at the
Scandinavian Conference on Cancer - Correct Answer ecological study
name that study design: Study investigators invited all male physicians in the UK to fill out
questionnaires regarding their health status and their smoking status. They then focused on the
healthy physicians who were willing to participate and mailed follow-up questionnaires to them
every 2 years. Using death certificate data the researchers noted the cause of death for any subjects
who became ill and died. The study continued for 50 years - Correct Answer prospective cohort study
Which of the following is NOT a purpose of randomization? - Correct Answer To match on exposure
purposes of randomization - Correct Answer To ensure that treatment is assigned in an unbiased
fashion
To ensure comparability between treatment groups
To minimize confounding
Which of the following is NOT an advantage of randomization? - Correct Answer It can minimize loss
to follow-up
advantages of randomization - Correct Answer It can control for known confounders
It can control for unknown confounders
It can ensure comparability between study groups
The Behavioral Risk Factor Surveillance System (BRFSS) collects information on health risks and
behaviors annually, through a random digit-dialing system every year.
What kind of study design is this? - Correct Answer Cross-Sectional Study
The Nurses' Health Study is a prospective cohort study that follows female nurses, aged 25-42. Which
of the following techniques does this study use to minimize confounding? - Correct Answer
Restriction
