C784 Applied Healthcare Statistics Practice Exam 2026 |WGU
1. In a simple linear regression model, which variable is also known as the
predictor variable?
A. Independent variable
B. Outcome variable
C. Dependent variable
D. Response variable
Answer: A
Rationale: The independent variable (X) is known as the predictor because it is used to
predict the value of the dependent variable (Y).
2. A researcher finds a Pearson’s r value of -0.85 between smoking and lung
capacity. How would you describe this correlation?
A. Strong positive correlation
B. Strong negative correlation
C. Weak negative correlation
D. No correlation
Answer: B
Rationale: A value of -0.85 indicates a strong relationship because it is close to -1, and the
negative sign indicates an inverse relationship.
,3. What does the coefficient of determination (R-squared) represent?
A. The probability that the null hypothesis is true
B. The average error in prediction
C. The slope of the regression line
D. The proportion of variance in the dependent variable explained by the independent variable
Answer: D
Rationale: R-squared measures how well the regression model explains the variability of
the dependent variable based on the independent variable.
4. If the p-value is 0.03 and the alpha level is 0.05, what should the researcher
do?
A. Reject the null hypothesis
B. Fail to reject the null hypothesis
C. Change the alpha level to 0.01
D. Accept the null hypothesis as true
Answer: A
Rationale: When the p-value is less than or equal to the alpha level (p <= 0.05), the results
are considered statistically significant, and the null hypothesis is rejected.
5. Which level of measurement categorizes data into mutually exclusive groups
with no inherent order?
A. Ordinal
B. Interval
C. Ratio
D. Nominal
Answer: D
Rationale: Nominal data consists of categories with no ranking or numerical value, such as
eye color or gender.
, 6. In a normal distribution, what percentage of the data falls within one
standard deviation of the mean?
A. 95%
B. 50%
C. 99.7%
D. 68%
Answer: D
Rationale: According to the Empirical Rule (68-95-99.7), approximately 68% of data in a
normal distribution falls within one standard deviation of the mean.
7. What is a Type I error?
A. Failing to reject a false null hypothesis
B. Rejecting a true null hypothesis
C. Accepting the alternative hypothesis when it is false
D. A calculation error in the mean
Answer: B
Rationale: A Type I error, also known as a ‘false positive,’ occurs when we reject a null
hypothesis that is actually true in the population.
8. A z-score of +2.0 indicates that a value is:
A. Two units above the mean
B. Two standard deviations below the mean
C. The mean of the distribution
D. Two standard deviations above the mean
Answer: D
Rationale: The z-score represents the number of standard deviations a data point is from
the mean. A positive value indicates it is above the mean.
1. In a simple linear regression model, which variable is also known as the
predictor variable?
A. Independent variable
B. Outcome variable
C. Dependent variable
D. Response variable
Answer: A
Rationale: The independent variable (X) is known as the predictor because it is used to
predict the value of the dependent variable (Y).
2. A researcher finds a Pearson’s r value of -0.85 between smoking and lung
capacity. How would you describe this correlation?
A. Strong positive correlation
B. Strong negative correlation
C. Weak negative correlation
D. No correlation
Answer: B
Rationale: A value of -0.85 indicates a strong relationship because it is close to -1, and the
negative sign indicates an inverse relationship.
,3. What does the coefficient of determination (R-squared) represent?
A. The probability that the null hypothesis is true
B. The average error in prediction
C. The slope of the regression line
D. The proportion of variance in the dependent variable explained by the independent variable
Answer: D
Rationale: R-squared measures how well the regression model explains the variability of
the dependent variable based on the independent variable.
4. If the p-value is 0.03 and the alpha level is 0.05, what should the researcher
do?
A. Reject the null hypothesis
B. Fail to reject the null hypothesis
C. Change the alpha level to 0.01
D. Accept the null hypothesis as true
Answer: A
Rationale: When the p-value is less than or equal to the alpha level (p <= 0.05), the results
are considered statistically significant, and the null hypothesis is rejected.
5. Which level of measurement categorizes data into mutually exclusive groups
with no inherent order?
A. Ordinal
B. Interval
C. Ratio
D. Nominal
Answer: D
Rationale: Nominal data consists of categories with no ranking or numerical value, such as
eye color or gender.
, 6. In a normal distribution, what percentage of the data falls within one
standard deviation of the mean?
A. 95%
B. 50%
C. 99.7%
D. 68%
Answer: D
Rationale: According to the Empirical Rule (68-95-99.7), approximately 68% of data in a
normal distribution falls within one standard deviation of the mean.
7. What is a Type I error?
A. Failing to reject a false null hypothesis
B. Rejecting a true null hypothesis
C. Accepting the alternative hypothesis when it is false
D. A calculation error in the mean
Answer: B
Rationale: A Type I error, also known as a ‘false positive,’ occurs when we reject a null
hypothesis that is actually true in the population.
8. A z-score of +2.0 indicates that a value is:
A. Two units above the mean
B. Two standard deviations below the mean
C. The mean of the distribution
D. Two standard deviations above the mean
Answer: D
Rationale: The z-score represents the number of standard deviations a data point is from
the mean. A positive value indicates it is above the mean.
