Section 1: Basic Epidemiological Concepts
- Which of the following is NOT an essential component of epidemiology?
a) Distribution
b) Causation
c) Prevention
d) Treatment - Incidence rate is best defined as:
a) The total number of new cases in a population at risk over a specific time period
b) The total number of existing cases in a population
c) The ratio of diseased to non-diseased individuals
d) The probability of survival after diagnosis - Prevalence is:
a) A measure of new cases in a population
b) A measure of both old and new cases in a population
c) The mortality rate of a disease
d) A measure of deaths per population - The epidemiological triad consists of:
a) Host, agent, environment
b) Incidence, prevalence, mortality
c) Disease, risk factor, prevention
d) Primary, secondary, tertiary prevention - Which of the following is an example of secondary prevention?
a) Vaccination
b) Cancer screening
c) Chemotherapy
d) Health education
Section 2: Study Designs
- Which of the following study designs is best for determining causality?
a) Cross-sectional study
b) Case-control study
c) Randomized controlled trial
d) Ecological study - A cohort study is characterized by:
a) Following participants over time based on exposure status
b) Comparing diseased and non-diseased groups retrospectively
c) Studying groups at a single point in time
d) Randomly assigning participants to treatment groups - Which study design is most suitable for rare diseases?
a) Cohort study
b) Case-control study
c) Cross-sectional study
d) Experimental study - Which of the following is NOT a characteristic of a case-control study?
a) It is retrospective
b) It is cost-effective
c) It provides incidence data
d) It is useful for rare diseases - The major disadvantage of an ecological study is:
a) High cost
b) Time-consuming nature
c) Ecological fallacy
d) Ethical concerns
Section 3: Measures of Association and Risk
- Relative risk is used in which type of study?
a) Cohort study
b) Case-control study
c) Cross-sectional study
d) Ecological study - Odds ratio is commonly used in:
a) Cohort studies
b) Cross-sectional studies
c) Case-control studies
d) Randomized trials - Attributable risk measures:
a) The proportion of disease due to an exposure
b) The rate of disease in the population
c) The survival rate of affected individuals
d) The error in study findings - If the relative risk (RR) is 1.5, it means:
a) No association between exposure and disease
b) Exposure increases disease risk by 50%
c) Exposure decreases disease risk
d) The disease is independent of exposure - A confidence interval that includes 1 means:
a) The association is statistically significant
b) The association is not statistically significant
c) There is a strong association
d) The study is biased
Section 4: Bias and Confounding
- Which of the following is a type of selection bias?
a) Recall bias
b) Loss to follow-up
c) Observer bias
d) Measurement bias - Confounding occurs when:
a) A third variable distorts the association between exposure and disease
b) The sample size is too small
c) The measurement tools are unreliable
d) There is selection bias - Randomization in clinical trials helps to:
a) Ensure treatment is effective
b) Control for confounding variables
c) Increase bias
d) Lower cost - Blinding is used to reduce:
a) Selection bias
b) Observer bias
c) Confounding
d) Incidence rate - Which of the following can reduce recall bias?
a) Increasing sample size
b) Using objective measurements
c) Increasing follow-up time
d) Randomly assigning exposure groups
Section 5: Public Health Applications
- The first step in an outbreak investigation is:
a) Identify the source
b) Confirm the existence of an outbreak
c) Implement control measures
d) Publish findings - Which measure is commonly used in surveillance?
a) Incidence rate
b) Attributable risk
c) Case-fatality rate
d) Sensitivity - The best source of national mortality data is:
a) Census
b) Hospital records
c) Vital registration system
d) Surveillance reports - The sensitivity of a test measures:
a) The ability to correctly detect disease
b) The ability to detect non-disease cases
c) The proportion of false positives
d) The rate of disease spread - Quarantine is an example of:
a) Primary prevention
b) Secondary prevention
c) Tertiary prevention
d) None of the above
Answer Key
- c
- a
- b
- a
- b
- c
- a
- b
- c
- c
- a
- c
- a
- b
- b
- b
- a
- b
- b
- b
- b
- a
- c
- a
- b