Epidemiology Midterm I Exam Latest 2027 –
Questions & Answers with Rationales | A+
Guaranteed Pass
Section 1: History, Definitions & Core Concepts (Questions 1–30)
1. Epidemiology is best defined as:
A) The study of the distribution and determinants of health-related states in populations
B) The study of individual disease processes
C) The study of hospital administration
D) The study of medical treatments
Correct Answer: A) The study of the distribution and determinants of health-related
states in populations
Epidemiology is the study of the distribution and determinants of health-related states or
events in specified populations, and the application of this study to control health problems.
2. Who is considered the father of epidemiology?
,A) Louis Pasteur
B) John Snow
C) Robert Koch
D) Alexander Fleming
Correct Answer: B) John Snow
John Snow is known as the father of epidemiology for his investigation of the 1854 cholera
outbreak in London, where he traced the source to the Broad Street water pump.
3. John Snow's investigation of cholera in London was significant because:
A) He discovered the cholera bacterium
B) He used mapping and data to identify the source of the outbreak
C) He developed the first vaccine
D) He invented the microscope
Correct Answer: B) He used mapping and data to identify the source of the outbreak
Snow's work demonstrated the use of epidemiological methods—mapping cases and
comparing exposures—to identify the source of a disease outbreak.
4. Which of the following is NOT a core function of epidemiology?
A) Describe the distribution of disease
B) Identify determinants of disease
,C) Provide individual clinical treatment
D) Evaluate interventions
Correct Answer: C) Provide individual clinical treatment
Epidemiology focuses on populations, not individual clinical treatment. Core functions
include description, explanation, prediction, and control of disease in populations.
5. The term "determinants" in epidemiology refers to:
A) The number of cases
B) Factors that influence the occurrence of disease
C) The geographic location of disease
D) The time of onset
Correct Answer: B) Factors that influence the occurrence of disease
Determinants are factors or exposures that influence the occurrence of disease, including
biological, behavioral, environmental, and social factors.
6. Which of the following is an example of a population-level intervention?
A) Prescribing antibiotics to a patient
B) Vaccination program
C) Individual counseling
D) Surgery
, Correct Answer: B) Vaccination program
Vaccination programs are population-level interventions that aim to prevent disease across
entire populations.
7. The epidemiological triangle consists of:
A) Host, agent, environment
B) Person, place, time
C) Incidence, prevalence, mortality
D) Bacteria, viruses, fungi
Correct Answer: A) Host, agent, environment
The epidemiological triangle (or triad) models disease causation as an interaction among
host, agent, and environment.
8. In the epidemiological triangle, the "agent" refers to:
A) The person who gets sick
B) The external factors that contribute to disease
C) The biological or physical cause of disease
D) The time of disease onset
Correct Answer: C) The biological or physical cause of disease
Questions & Answers with Rationales | A+
Guaranteed Pass
Section 1: History, Definitions & Core Concepts (Questions 1–30)
1. Epidemiology is best defined as:
A) The study of the distribution and determinants of health-related states in populations
B) The study of individual disease processes
C) The study of hospital administration
D) The study of medical treatments
Correct Answer: A) The study of the distribution and determinants of health-related
states in populations
Epidemiology is the study of the distribution and determinants of health-related states or
events in specified populations, and the application of this study to control health problems.
2. Who is considered the father of epidemiology?
,A) Louis Pasteur
B) John Snow
C) Robert Koch
D) Alexander Fleming
Correct Answer: B) John Snow
John Snow is known as the father of epidemiology for his investigation of the 1854 cholera
outbreak in London, where he traced the source to the Broad Street water pump.
3. John Snow's investigation of cholera in London was significant because:
A) He discovered the cholera bacterium
B) He used mapping and data to identify the source of the outbreak
C) He developed the first vaccine
D) He invented the microscope
Correct Answer: B) He used mapping and data to identify the source of the outbreak
Snow's work demonstrated the use of epidemiological methods—mapping cases and
comparing exposures—to identify the source of a disease outbreak.
4. Which of the following is NOT a core function of epidemiology?
A) Describe the distribution of disease
B) Identify determinants of disease
,C) Provide individual clinical treatment
D) Evaluate interventions
Correct Answer: C) Provide individual clinical treatment
Epidemiology focuses on populations, not individual clinical treatment. Core functions
include description, explanation, prediction, and control of disease in populations.
5. The term "determinants" in epidemiology refers to:
A) The number of cases
B) Factors that influence the occurrence of disease
C) The geographic location of disease
D) The time of onset
Correct Answer: B) Factors that influence the occurrence of disease
Determinants are factors or exposures that influence the occurrence of disease, including
biological, behavioral, environmental, and social factors.
6. Which of the following is an example of a population-level intervention?
A) Prescribing antibiotics to a patient
B) Vaccination program
C) Individual counseling
D) Surgery
, Correct Answer: B) Vaccination program
Vaccination programs are population-level interventions that aim to prevent disease across
entire populations.
7. The epidemiological triangle consists of:
A) Host, agent, environment
B) Person, place, time
C) Incidence, prevalence, mortality
D) Bacteria, viruses, fungi
Correct Answer: A) Host, agent, environment
The epidemiological triangle (or triad) models disease causation as an interaction among
host, agent, and environment.
8. In the epidemiological triangle, the "agent" refers to:
A) The person who gets sick
B) The external factors that contribute to disease
C) The biological or physical cause of disease
D) The time of disease onset
Correct Answer: C) The biological or physical cause of disease
