Public Health Epidemiology & Biostatistics Exam 2026:
Comprehensive University/Graduate/Professional Certification
Practice Examination — Epidemiologic Methods, Study Designs,
Disease Surveillance, Measures of Disease Frequency, Bias &
Confounding, Screening, Biostatistical Analysis, Probability,
Hypothesis Testing, Regression & Public Health Research — 195
Multiple-Choice Questions with Answers & Detailed Rationales
SECTION 1: EPIDEMIOLOGICAL CONCEPTS AND MEASURES (Questions 1–30)
Question 1
Which measure of disease frequency is defined as the proportion of a population that has a
disease at a specific point in time?
A. Incidence rate
B. Point prevalence
C. Attack rate
D. Cumulative incidence
Correct Answer: B
Explanation: Point prevalence quantifies existing disease burden at a single moment, unlike
incidence measures that capture new cases over time.
Question 2
A researcher wants to measure the speed at which new cases of influenza develop in a
population during an outbreak. Which measure is most appropriate?
,A. Point prevalence
B. Period prevalence
C. Incidence rate
D. Case fatality rate
Correct Answer: C
Explanation: Incidence rate measures the velocity of new case occurrence per person-time,
ideal for outbreak dynamics and temporal comparisons.
Question 3
In a cohort study of 500 workers, 25 develop carpal tunnel syndrome over 5 years. What is
the cumulative incidence?
A. 2.5%
B. 5%
C. 10%
D. 25%
Correct Answer: B
Explanation: Cumulative incidence = 25/500 = 0.05 or 5%, representing risk of developing
disease over the specified period.
Question 4
Which of the following best describes the difference between incidence and prevalence?
,A. Incidence measures existing cases; prevalence measures new cases
B. Incidence measures new cases; prevalence measures existing cases
C. Both measure new cases but in different populations
D. Both measure existing cases but at different times
Correct Answer: B
Explanation: Incidence captures new disease occurrence; prevalence captures all existing
cases, reflecting both incidence and disease duration.
Question 5
A disease with high incidence but short duration will have:
A. High prevalence
B. Low prevalence
C. Prevalence equal to incidence
D. Prevalence unrelated to incidence
Correct Answer: B
Explanation: Prevalence approximates incidence × duration; short duration limits
accumulation, keeping prevalence low despite high incidence.
Question 6
Which mortality measure is most useful for comparing disease severity across populations?
, A. Crude mortality rate
B. Case fatality rate
C. Proportional mortality ratio
D. Age-adjusted mortality rate
Correct Answer: B
Explanation: Case fatality rate measures the proportion of diagnosed cases who die, directly
reflecting disease severity independent of population size.
Question 7
In 2023, a city reported 1,200 deaths from cardiovascular disease among 300,000 residents.
What is the cause-specific mortality rate per 100,000?
A. 40
B. 400
C. 4,000
D. 250
Correct Answer: B
Explanation: Cause-specific mortality rate = (1,200/300,000) × 100,000 = 400 per 100,000
population.
Question 8
Which measure describes the proportion of all deaths attributable to a specific cause?
Comprehensive University/Graduate/Professional Certification
Practice Examination — Epidemiologic Methods, Study Designs,
Disease Surveillance, Measures of Disease Frequency, Bias &
Confounding, Screening, Biostatistical Analysis, Probability,
Hypothesis Testing, Regression & Public Health Research — 195
Multiple-Choice Questions with Answers & Detailed Rationales
SECTION 1: EPIDEMIOLOGICAL CONCEPTS AND MEASURES (Questions 1–30)
Question 1
Which measure of disease frequency is defined as the proportion of a population that has a
disease at a specific point in time?
A. Incidence rate
B. Point prevalence
C. Attack rate
D. Cumulative incidence
Correct Answer: B
Explanation: Point prevalence quantifies existing disease burden at a single moment, unlike
incidence measures that capture new cases over time.
Question 2
A researcher wants to measure the speed at which new cases of influenza develop in a
population during an outbreak. Which measure is most appropriate?
,A. Point prevalence
B. Period prevalence
C. Incidence rate
D. Case fatality rate
Correct Answer: C
Explanation: Incidence rate measures the velocity of new case occurrence per person-time,
ideal for outbreak dynamics and temporal comparisons.
Question 3
In a cohort study of 500 workers, 25 develop carpal tunnel syndrome over 5 years. What is
the cumulative incidence?
A. 2.5%
B. 5%
C. 10%
D. 25%
Correct Answer: B
Explanation: Cumulative incidence = 25/500 = 0.05 or 5%, representing risk of developing
disease over the specified period.
Question 4
Which of the following best describes the difference between incidence and prevalence?
,A. Incidence measures existing cases; prevalence measures new cases
B. Incidence measures new cases; prevalence measures existing cases
C. Both measure new cases but in different populations
D. Both measure existing cases but at different times
Correct Answer: B
Explanation: Incidence captures new disease occurrence; prevalence captures all existing
cases, reflecting both incidence and disease duration.
Question 5
A disease with high incidence but short duration will have:
A. High prevalence
B. Low prevalence
C. Prevalence equal to incidence
D. Prevalence unrelated to incidence
Correct Answer: B
Explanation: Prevalence approximates incidence × duration; short duration limits
accumulation, keeping prevalence low despite high incidence.
Question 6
Which mortality measure is most useful for comparing disease severity across populations?
, A. Crude mortality rate
B. Case fatality rate
C. Proportional mortality ratio
D. Age-adjusted mortality rate
Correct Answer: B
Explanation: Case fatality rate measures the proportion of diagnosed cases who die, directly
reflecting disease severity independent of population size.
Question 7
In 2023, a city reported 1,200 deaths from cardiovascular disease among 300,000 residents.
What is the cause-specific mortality rate per 100,000?
A. 40
B. 400
C. 4,000
D. 250
Correct Answer: B
Explanation: Cause-specific mortality rate = (1,200/300,000) × 100,000 = 400 per 100,000
population.
Question 8
Which measure describes the proportion of all deaths attributable to a specific cause?
