Certified in Public Health (CPH) Examination
Practice Exam Questions And Correct
Answers (Verified Answers) Plus Rationales
2026 Q&A Instant Downlo ad Pdf
Section 1: Evidence-Based Approaches to Public Health & Epidemiology
1. Which of the following evaluates asymmetry in a distribution?
A) Kurtosis
B) Skew
C) Range
D) Confidence interval
Correct ,,,answer,,,,: B - Skew
Rationale: Skew refers to the symmetry of the distribution curve. Positive skew
means the tail extends to the right (mean > median), while negative skew means
the tail extends to the left (mean < median). Kurtosis measures "peakedness,"
range measures dispersion, and confidence intervals estimate parameters.
2. A measure of the "peakedness" of the probability distribution of a real-
valued random variable is called:
A) Skew
B) Variance
,C) Kurtosis
D) Standard deviation
Correct ,,,answer,,,,: C - Kurtosis
Rationale: Kurtosis measures the tail heaviness and peakedness of a distribution
relative to a normal distribution. High kurtosis indicates heavy tails and a sharp
peak; low kurtosis indicates light tails and a flatter peak.
3. Count data, such as the number of events occurring in a specified period of
time, are often described by which probability distribution?
A) Binomial
B) Chi-square
C) Normal
D) Poisson
Correct ,,,answer,,,,: D - Poisson
Rationale: The Poisson distribution is used to model count data—the number of
events occurring in a fixed interval of time or space. It assumes events occur
independently and at a constant average rate. The binomial distribution models
number of successes in a fixed number of trials.
4. The probability distribution for the number of successes in a sequence of
Bernoulli trials (trials where each trial can either succeed or fail, trials are
independent, and the probability of success is the same for each trial) is the:
,A) Poisson distribution
B) Normal distribution
C) Binomial distribution
D) Chi-square distribution
Correct ,,,answer,,,,: C - Binomial distribution
Rationale: The binomial distribution models the number of successes in a fixed
number of independent trials, each with the same probability of success. This is the
classic "coin flip" distribution.
5. Which distribution is a right-skewed distribution where the area under the
curve equals one, starts at 0 on the x-axis and extends infinitely to the right,
and looks increasingly normal as degrees of freedom increase?
A) Normal distribution
B) Chi-square distribution
C) Binomial distribution
D) Poisson distribution
Correct ,,,answer,,,,: B - Chi-square distribution
Rationale: The chi-square distribution is right-skewed and approaches normality as
degrees of freedom increase. It is used in hypothesis testing for categorical data,
goodness-of-fit tests, and tests of independence in contingency tables.
6. The t-distribution approaches which distribution as its degrees of freedom
increases?
, A) Exponential distribution
B) Normal distribution
C) Binomial distribution
D) Chi-square distribution
Correct ,,,answer,,,,: B - Normal distribution
Rationale: As degrees of freedom increase, the t-distribution converges to the
standard normal distribution. This is why the t-distribution is used for small sample
sizes (when the population standard deviation is unknown) and the normal
distribution is used for large samples.
7. River water pollution due to stormwater runoff from chemically fertilized
farm fields is an example of:
A) Point source pollution
B) Non-point source pollution
C) Accidental and unforeseeable pollution
D) Unpreventable pollution
Correct ,,,answer,,,,: B - Non-point source pollution
Rationale: Non-point source pollution comes from diffuse sources that cannot be
traced to a single point of discharge. Agricultural runoff from fertilized fields is a
classic example, as it enters water bodies across a wide area. Point source
pollution comes from identifiable sources like pipes or smokestacks.
Practice Exam Questions And Correct
Answers (Verified Answers) Plus Rationales
2026 Q&A Instant Downlo ad Pdf
Section 1: Evidence-Based Approaches to Public Health & Epidemiology
1. Which of the following evaluates asymmetry in a distribution?
A) Kurtosis
B) Skew
C) Range
D) Confidence interval
Correct ,,,answer,,,,: B - Skew
Rationale: Skew refers to the symmetry of the distribution curve. Positive skew
means the tail extends to the right (mean > median), while negative skew means
the tail extends to the left (mean < median). Kurtosis measures "peakedness,"
range measures dispersion, and confidence intervals estimate parameters.
2. A measure of the "peakedness" of the probability distribution of a real-
valued random variable is called:
A) Skew
B) Variance
,C) Kurtosis
D) Standard deviation
Correct ,,,answer,,,,: C - Kurtosis
Rationale: Kurtosis measures the tail heaviness and peakedness of a distribution
relative to a normal distribution. High kurtosis indicates heavy tails and a sharp
peak; low kurtosis indicates light tails and a flatter peak.
3. Count data, such as the number of events occurring in a specified period of
time, are often described by which probability distribution?
A) Binomial
B) Chi-square
C) Normal
D) Poisson
Correct ,,,answer,,,,: D - Poisson
Rationale: The Poisson distribution is used to model count data—the number of
events occurring in a fixed interval of time or space. It assumes events occur
independently and at a constant average rate. The binomial distribution models
number of successes in a fixed number of trials.
4. The probability distribution for the number of successes in a sequence of
Bernoulli trials (trials where each trial can either succeed or fail, trials are
independent, and the probability of success is the same for each trial) is the:
,A) Poisson distribution
B) Normal distribution
C) Binomial distribution
D) Chi-square distribution
Correct ,,,answer,,,,: C - Binomial distribution
Rationale: The binomial distribution models the number of successes in a fixed
number of independent trials, each with the same probability of success. This is the
classic "coin flip" distribution.
5. Which distribution is a right-skewed distribution where the area under the
curve equals one, starts at 0 on the x-axis and extends infinitely to the right,
and looks increasingly normal as degrees of freedom increase?
A) Normal distribution
B) Chi-square distribution
C) Binomial distribution
D) Poisson distribution
Correct ,,,answer,,,,: B - Chi-square distribution
Rationale: The chi-square distribution is right-skewed and approaches normality as
degrees of freedom increase. It is used in hypothesis testing for categorical data,
goodness-of-fit tests, and tests of independence in contingency tables.
6. The t-distribution approaches which distribution as its degrees of freedom
increases?
, A) Exponential distribution
B) Normal distribution
C) Binomial distribution
D) Chi-square distribution
Correct ,,,answer,,,,: B - Normal distribution
Rationale: As degrees of freedom increase, the t-distribution converges to the
standard normal distribution. This is why the t-distribution is used for small sample
sizes (when the population standard deviation is unknown) and the normal
distribution is used for large samples.
7. River water pollution due to stormwater runoff from chemically fertilized
farm fields is an example of:
A) Point source pollution
B) Non-point source pollution
C) Accidental and unforeseeable pollution
D) Unpreventable pollution
Correct ,,,answer,,,,: B - Non-point source pollution
Rationale: Non-point source pollution comes from diffuse sources that cannot be
traced to a single point of discharge. Agricultural runoff from fertilized fields is a
classic example, as it enters water bodies across a wide area. Point source
pollution comes from identifiable sources like pipes or smokestacks.
