HLTH 485
Principles of Epidemiology & Biostatistics
Midterms Exam Review (Qns & Ans)
2025
1. What measure is used to express the rate of new cases of a
disease in a defined population over a specific period of time?
- A. Prevalence
- B. Incidence Rate
- C. Mortality Rate
- D. Case Fatality Rate
- ANS: B. Incidence Rate
- Rationale: Incidence rate measures the rate of new cases of a
disease in a specified population over a given period.
©/2025
,2. Which of the following is NOT a common type of
epidemiological study design?
- A. Cohort Study
- B. Case-Control Study
- C. Cross-Sectional Study
- D. Longitudinal Study
- ANS: D. Longitudinal Study
- Rationale: While longitudinal studies are used in research,
they are not specific to epidemiology alone.
3. The p-value in statistical testing represents:
- A. The probability of the null hypothesis being true
- B. The probability of observing the data given that the null
hypothesis is true
- C. The probability of observing the data given that the
alternative hypothesis is true
- D. The strength of the relationship between two variables
- ANS: B. The probability of observing the data given that the
null hypothesis is true
- Rationale: A p-value indicates the probability of obtaining
the observed data if the null hypothesis is correct.
©/2025
, Fill-in-the-Blank Questions
4. A ________ study follows a group of individuals over time to
observe how their exposures affect their outcomes.
- ANS: Cohort
- Rationale: A cohort study tracks a group of individuals over
time to examine the association between exposures and outcomes.
5. The ________ is the middle value of a data set when it is
ordered from least to greatest.
- ANS: Median
- Rationale: The median is the value that separates a data set
into two equal halves.
6. In biostatistics, ________ refers to the average value of a data
set.
- ANS: Mean
- Rationale: The mean is calculated by summing all values
and dividing by the number of values.
True/False Questions
7. True or False: A case-control study is prospective in nature.
- ANS: False
©/2025
, - Rationale: Case-control studies are retrospective, meaning
they look back at data from past cases and controls.
8. True or False: Confounding variables can distort the true
relationship between an exposure and an outcome.
- ANS: True
- Rationale: Confounding variables can introduce bias and
affect the apparent relationship between variables.
9. True or False: The primary goal of epidemiology is to
determine the effectiveness of medical treatments.
- ANS: False
- Rationale: Epidemiology aims to study the distribution and
determinants of health-related states and events in populations.
Multiple Response Questions
10. Which of the following are key principles of epidemiology?
(Select all that apply)
- A. Distribution
- B. Determinants
- C. Intervention
- D. Eradication
©/2025
Principles of Epidemiology & Biostatistics
Midterms Exam Review (Qns & Ans)
2025
1. What measure is used to express the rate of new cases of a
disease in a defined population over a specific period of time?
- A. Prevalence
- B. Incidence Rate
- C. Mortality Rate
- D. Case Fatality Rate
- ANS: B. Incidence Rate
- Rationale: Incidence rate measures the rate of new cases of a
disease in a specified population over a given period.
©/2025
,2. Which of the following is NOT a common type of
epidemiological study design?
- A. Cohort Study
- B. Case-Control Study
- C. Cross-Sectional Study
- D. Longitudinal Study
- ANS: D. Longitudinal Study
- Rationale: While longitudinal studies are used in research,
they are not specific to epidemiology alone.
3. The p-value in statistical testing represents:
- A. The probability of the null hypothesis being true
- B. The probability of observing the data given that the null
hypothesis is true
- C. The probability of observing the data given that the
alternative hypothesis is true
- D. The strength of the relationship between two variables
- ANS: B. The probability of observing the data given that the
null hypothesis is true
- Rationale: A p-value indicates the probability of obtaining
the observed data if the null hypothesis is correct.
©/2025
, Fill-in-the-Blank Questions
4. A ________ study follows a group of individuals over time to
observe how their exposures affect their outcomes.
- ANS: Cohort
- Rationale: A cohort study tracks a group of individuals over
time to examine the association between exposures and outcomes.
5. The ________ is the middle value of a data set when it is
ordered from least to greatest.
- ANS: Median
- Rationale: The median is the value that separates a data set
into two equal halves.
6. In biostatistics, ________ refers to the average value of a data
set.
- ANS: Mean
- Rationale: The mean is calculated by summing all values
and dividing by the number of values.
True/False Questions
7. True or False: A case-control study is prospective in nature.
- ANS: False
©/2025
, - Rationale: Case-control studies are retrospective, meaning
they look back at data from past cases and controls.
8. True or False: Confounding variables can distort the true
relationship between an exposure and an outcome.
- ANS: True
- Rationale: Confounding variables can introduce bias and
affect the apparent relationship between variables.
9. True or False: The primary goal of epidemiology is to
determine the effectiveness of medical treatments.
- ANS: False
- Rationale: Epidemiology aims to study the distribution and
determinants of health-related states and events in populations.
Multiple Response Questions
10. Which of the following are key principles of epidemiology?
(Select all that apply)
- A. Distribution
- B. Determinants
- C. Intervention
- D. Eradication
©/2025
