Week 1 Problems
20 questions, 30 points
Chapter 1 Chapter 2
1. D. margin of error 1. A3, B10, C7, D1, E9
2. A. sample 2. D. case-control study
3. D. A and C 3. A. case-control study
4. C. no increased risk 4. B. randomized control trial
5. D. inappropriately accounting for
relationships
5. Cohort study
6. True 6. True
7. False 7. False
8. True 8. True
9. False 9. True
10. True 10. True
Chapter 1
1. The measure of uncertainty in a biostatistician’s calculation of a particular outcome that may
result from using a subset of the population to estimate the actual likelihood of the event
occurring in the population as a whole is referred to by what statistical term?
A) A chance error
B) A systematic error
C) A standard error
D) A margin of error
2. A subset of the population of interest is often referred to by what statistical term?
A) A sample of individuals
B) A subculture of individuals
C) A class of individuals
D) A minority group
3. The most appropriate study design depends, among other things, on the distribution of
A) The risk factor in the population of interest
B) The participants
C) The outcome in the population of interest
D) A & C
4. The interpretation of a relative risk equal to 1 suggest:
A) An increase in risk
B) A decrease in risk
C) No increased risk
D) None of the above
5. Appropriately conducting and interpreting biostatistical applications require attention to a
number of important issues. These include, but are not limited to, the following except:
A) Clearly defining the objective or research question
B) Selecting a representative sample, and ensuring that the sample is of sufficient size
C) Quantifying uncertainty
D) Inappropriately accounting for relationships among characteristics
True/False
6. True or False? Biostatistics is defined as the application of statistical principles in medicine,
public health, or biology.
7. True or False? The data collected in a biostatistics study can be applied to any population
regardless of race, class, and socioeconomic status.
8. True/False? Epidemiology is a field of study focused on the study of health and illness in
human populations, patterns of health or disease, and the factors that influence these patterns.
9. True/ False? The ideal study design from a statistical point of view is the case control study.
10. True/ False? In a clinical trial, if we observe a large difference in cholesterol levels between
participants receiving the experimental drug and the placebo or comparator, we can infer that the
experimental drug is effective.
Chapter 2
1. Match the definitions to the appropriate words.
Term Description
A. Bias ____ 1. A group of participants who usually share
some common characteristics and
monitored or followed over time
B. Clinical Trial ____ 2. Strongly associated with outcome
C. Confounding ____ 3. Systematic uncertainty
D. Cohort____ 4. At a single point in time
E.Prevalence of disease____ 5. Subjects receive two or more treatments
6. Creating similar comparison groups
7. Risk factor distortion
8. Number of new cases of disease over time
9. The proportion of individuals with the
condition at a single point in time
10. Subject randomly assigned to treatment
groups
2. Misclassification bias is most likely to be observed in which study type?
A) A randomized control trial
B) A cross-sectional survey
C) A prospective cohort
D) A case-control study
3. An investigator reviewed the medical records of 200 children seen for care at Boston Medical
Center in the past year who were between the ages 8 and 12 and identified 40 children with
asthma. He also identified 40 children of the same ages who were free of asthma. Each child and
their family were interviewed to assess whether there might be an association between certain
environmental factors such as exposure to second-hand smoke. This study is an example of a:
A) Case-Control Study
B) Crossover Trial
C) Cohort Study
D) Randomized Control Trial
4. A study is planned to assess the effect of a new surgical intervention for gallbladder disease.
One hundred patients with gallbladder disease will be randomly assigned to receive either the
new surgical intervention or the standard surgical intervention. The efficacy of the new surgical
intervention will be measured by the time a patient takes to return to normal activities, recorded
in days. Identify the type of study proposed
A) Cohort Study
B) Randomized Control Trial
C) Case-Control Study
D) Cross-Sectional Survey
5. A study is planned to investigate risk factors for sudden cardiac death. A cohort of men and
women between the ages of 35 and 70 are enrolled and followed for up to 20 years. As part of
the study, participants provide data on demographic and behavioral characteristics, they also
undergo testing for cardiac function and provide a blood samples to assess lipid profiles and
other biomarkers. A new measure of inflammation is hypothesized to be related to sudden
cardiac death. What study design is most appropriate to assess the association between the new
biomarker and sudden cardiac death.
True/False
6. True or False? An active-control trial is the best option for researchers hoping to test a newly
devised therapy for a life-threatening illness among individuals with the illness, when a
previously devised treatment is available for the illness.
7. True or False? A clinical trial is a type of observational study design.
8. True or False? Confounding is usually a major issue in cohort studies.
9. A case series is a systematic review of the interesting and common features of a small
collection, or series, of cases.
10. A cohort study involves a group of individuals who has a disease compared to a similar group
without the disease.
