Q1)Which of the following best defines a cohort study?
Anonymous Quiz
3%
A) A study where participants are randomly assigned to different interventions
74%
B) A study that follows a group of individuals over time to assess the incidence of disease
18%
C) A study that compares the prevalence of disease in different populations at a single point in tim
6%
D) A study that focuses on the distribution of disease within a population
Q2)Which of the following is a key characteristic of a cohort study?
Anonymous Quiz
0%
A) Randomization
9%
B) Retrospective data collection only
12%
C) Blinding of participants and investigators
79%
D) Longitudinal follow-up
Q3)Which of the following is a distinguishing feature of a prospective cohort study?
Anonymous Quiz
0%
A) The study starts after the outcomes have occurred
93%
B) The study follows participants forward in time from exposure to outcome
3%
C) The study is conducted on recorded data
3%
D) The study is usually cross-sectional in nature
Q4)Which of the following is an advantage of cohort studies over case-control studies?
Anonymous Quiz
0%
A) They are more time-efficient
13%
B) They are less expensive to conduct
84%
C) They provide a higher level of evidence for causal relationships
3%
D) They require fewer participants
Q5)A retrospective cohort study differs from a prospective cohort study in that:
Anonymous Quiz
6%
A) It is conducted in a shorter time frame
84%
B) It starts with the outcome and looks back to determine the exposure
3%
C) It follows participants forward in time from exposure to outcome
6%
D) It is always more reliable than a prospective study
Q6)The term 'person-years' is used in cohort studies to describe:
Anonymous Quiz
11%
A) The total number of participants in the study
46%
B) The number of years each participant has been followed
39%
C) The total time that all participants have been at risk for the outcome
4%
D) The average age of participants at the start of the study
Q7)A 95% confidence interval for a relative risk that includes 1.0 indicates:
Anonymous Quiz
14%
A) The exposure is significantly associated with the outcome
79%
B) The results are not statistically significant
3%
C) The study has a high level of precision
3%
D) The outcome is rare in the exposed group
Q8)Cohort studies are particularly useful for studying:
Anonymous Quiz
7%
A) Rare diseases
62%
B) Multiple outcomes of a single exposure
28%
C) Diseases with long latency periods
3%
D) The prevalence of disease in a population
Q9)Loss to follow-up in a cohort study can lead to:
Anonymous Quiz
3%
A) Increased study power
48%
B) Selection bias
29%
C) Misclassification of exposure
19%
D)all of the above
Q10)One major limitation of cohort studies is:
Anonymous Quiz
13%
A) The inability to study rare exposures
13%
B) The potential for high costs and long duration
7%
C) The difficulty in obtaining accurate exposure data
67%
D)B+C
Q11)A researcher wants to examine the long-term effects of childhood obesity on adult cardiovascular health. Which study design would be most appropriate?
Anonymous Quiz
7%
A) Retrospective cohort study
37%
B) Prospective cohort study
7%
C) Case-control study
50%
D) Both A & B
Q12)All of the following are reasons to conduct a cohort study except:
Anonymous Quiz
17%
A) To determine the incidence of disease in an exposed population
17%
B) To establish a cause-and-effect relationship between exposure and outcome
63%
C) To study rare diseases
3%
D) To examine multiple outcomes
A researcher collected the following data on the number of hours spent studying per week by five students: 8, 10, 12, 14, and 16 hours. What is the sample average (mean) number of hours spent studying per week?
Anonymous Quiz
81%
A) 12 hours
6%
B) 11.6 hours
6%
C) 13 hours
6%
D) 12.5 hours
A researcher collects data on the number of daily steps taken by 11 individuals: 3500, 4200, 4700, 5000, 5200, 5400, 5600, 5800, 6300, 6700, and 15000. What is the median number of steps taken?