Epidemiology Exam 2 Quiz Questions
Which of the following may result from the inability to use randomization in a cohort study? A. The possibility that a higher proportion of non-exposed persons may be included in the study B. The study will take longer to conduct if randomization is not used C. The possibility that a higher proportion of exposed persons may be included in the study D. The possibility that a factor which leads to exposure may be causally associated with the disease
The possibility that a factor which leads to exposure may be causally associated with the disease
Rank the 5 study designs in order of the evidence hierarchy: Case control Case series RCT Cohort Cross sectional
1. RCT 2. Cohort 3. Case Control 4. Cross-Sectional 5. Case Series
A group of investigators is examining the impact of air pollution on the development of asthma in children living in metropolitan areas. They obtained informed consent to recruit children, aged 4-6, into their study and followed them up through age 18. The primary exposure-outcome relationship they studied was whether higher levels of air pollution lead to an increased risk of asthma. This is an example of a ______ study design. A. Cross-sectional B. Case-control C. Randomized Controlled Trial D. Cohort
Cohort
A study was designed to assess the impact of sun exposure on skin damage in beach volleyball players. Players on SEC teams always use a popular brand of waterproof SPF 30 sunscreen whereas Big10 schools never use sunscreen. At the end of a weekend tournament, players skin from both teams was analyzed for skin damage and burns. What type of study design was used in this study? A. Case-control B. Randomized controlled clinical trial C. Cross-sectional D. Cohort
Cohort
Examples of descriptive epidemiologic studies do not usually include: A. Cross-sectional studies B. Case series C. Counts D. Cohort studies
Cohort
If a participant enters a study based on exposure, what study design has been used?
Cohort
If a participant enters a study neither based on exposure or outcome, what study design has been used?
Cross-sectional, doesn't test hypotheses
The Centers for Disease Control has produced a report on disparities in breast cancer rates. This is an example of which of the following: A. Popular literature B. News article C. Grey literature D. Scholarly literature
Grey literature
Which of the following is not generally included in a peer-reviewed original research article in epidemiology? A. Testimonials from individuals who have benefited from the research B. Discussion of other studies done on this topic C. Number of study participants D. Statistical methods used in analysis
Testimonials from individuals who have benefited from the research
All of the following are potential benefits of a randomized controlled trial, EXCEPT: A. Assignment of the next subject cannot be predicted B. The therapy that a subject receives is not influenced by either conscious or subconscious bias of the investigator. C. The external validity of the study is increased D. Self-selection for a particular treatment is eliminated E. The likelihood that the study groups will be comparable is increased
The external validity of the study is increased
Which of the following circumstances would warrant the use of a cohort study design? A. The incidence of the disease is high in the exposed group B. The disease under study occurs rarely in the population C. The study population is the same with regard to the risk factors for disease D. The incidence of the disease is high in the nonexposed group
The incidence of the disease is high in the exposed group
True or false? The researchers cited in a peer-reviewed article have published papers consistent with the authors' conclusions.
False
If the incidence of a disease among the exposed group is 10 per 100,000 and the incidence of disease among the unexposed is 2.5 per 100,000, what is the relative risk? A. 4.0 B. 2.0 C. 5.0 D. 1.0
4
For what reason was the Tuskegee Syphilis Study unethical? A. Participants never gave informed consent to participate B. Participants were never given appropriate treatment after it became available C. Participants were penalized with loss of benefits if they withdrew from study D. All of the above
All of the above
Randomized controlled trials contain which of the following components: A. Rigorous inclusion and exclusion criteria B. Blinding or masking to prevent bias C. Comparable measurement of outcomes in treatment and control conditions D. All of the above
All of the above
Which factor(s) distinguish study designs from one another? A. Data collection methods B. Unit of observation C. Timing of data collection D. All of the above
All of the above
Which of the following types of literature undergoes the most scientific scrutiny before publication? A. Article in the Washington Post B. Article published in the New England Journal of Medicine C. Report written for the American Cancer Society D. Article in a trade journal for mechanical engineers
Article published in the New England Journal of Medicine
If a participant enters a study based on outcome, what study design has been used?
Case Control
Which of the following is NOT considered an analytic study design? A. Case series B. Cohort C. Randomized Controlled Trial D. Case-Control
Case series
Which of the following is not a research design employed in descriptive epidemiology? A. Case report B. Case-control C. Cross-sectional D. Case series
Case-control
Researchers wanted to study the effects of exposure to pesticides in the workplace and the development of various outcomes. The researchers chose a group of farmers who routinely used pesticides and a group of farmers who did not use pesticides and followed them for 10 years for the development of various outcomes. This is an example of ___________ sampling. A. Exposure based B. Population based
Exposure based
In contingency tables (also called 2x2 tables), the rows are represented by: A. External Validity B. Disease Status C. Exposure Status D. Random Assignment
Exposure status
True or False? Analytic study designs allow the researcher to generate a hypothesis whereas a descriptive study design does not.
False
True or False? In a randomized controlled trial, participants must always be blinded.
False
True or false? In order to be published, an original peer-reviewed research article must cite the previous work of the journal's reviewers.
False
The New England Journal of Medicine published a case-control study of 200 women with colon cancer from the Iowa Women's Health Study. This journal article is an example of: A. Popular literature B. Scholarly Literature C. Trade Literature D. Gray Literature
Scholarly
In a 2x2 table, which exposure-outcome group is displayed in the top right corner? A. Subjects with the exposure and the outcome B. Subjects with the exposure but not the outcome C. Subjects with neither the exposure nor the outcome D. Subjects with the outcome but not the exposure
Subjects with the exposure but not the outcome
In an RCT, 3234 nondiabetic persons with elevated fasting and post-load plasma glucose concentrations were randomly assigned to one of 3 groups: (1) placebo; (2) medication; or (3) lifestyle-modification with the goals of at least a 7 percent weight loss and at least 150 minutes of physical activity per week. The incidence of diabetes was 11.0, 7.8, and 4.8 cases per 100 person-years in the placebo, medication, and lifestyle groups, respectively. Based on the information above, what is the correct interpretation? A. The placebo didn't work because they had the lowest risk B. The risk in the lifestyle-modification group was less than half of that in the placebo group C. The medication and lifestyle-modification groups had similar risks D. Randomization did not achieve comparable groups
The risk in the lifestyle-modification group was less than half of that in the placebo group
Researchers were interested in the effects of using olive oil on a daily basis on the risk of a second heart attack in men who had already had one heart attack. Men who used olive oil on a daily basis were compared to men who used butter in their diet. The men were followed over 5 years to determine whether the participants had a second heart attack. The RR estimate comparing regular olive oil users to men who usually used butter was 0.80. Which of the following is the best interpretation in words of this RR estimate? A. The risk of a second heart attack was 1.8 times higher in men who used olive oil compared to men who used butter. B. The risk of a second heart attack in men who had a previous heart attack was 20% reduced in men who used olive oil compared to men who used butter. C. The risk using olive oil was 20% lower in men who had a second heart attack compared to men who had only one heart attack. D. The risk of a second heart attack was lower in men who used olive oil compared to men who used butter.
The risk of a second heart attack in men who had a previous heart attack was 20% reduced in men who used olive oil compared to men who used butter.
Which of the following statements best represents the purpose of a research design in epidemiologic research? A. To increase funding for a research program B. To plan a program that will improve the population's health C. To provide a plan for valid study of a research question D. To prove that an intervention is effective
To provide a plan for valid study of a research question
True or False? Descriptive studies often collect data on person, place, and time.
True
True or False? In a cohort study, all potential study subjects must be initially free of the disease under investigation.
True
