WGU C784 APPLIED HEALTHCARE
STATISTICS COMPREHENSIVE EXAM
1. A researcher is studying the effects of a new hypertension medication. The null hypothesis
states that there is no difference in blood pressure between the treatment and placebo
groups. If the researcher rejects the null hypothesis when it is actually true, what has
occurred?
A. A Type II error
B. A Type I error
C. A correct decision
D. A sampling bias error
Answer: B
Conceptual Explanation: A Type I error occurs when the null hypothesis is rejected even
though it is true (a false positive).
,2. In a dataset representing patient recovery times, the distribution is heavily skewed to the
right. Which measure of central tendency would be most appropriate to describe the
‘average’ recovery time?
A. Mean
B. Mode
C. Median
D. Range
Answer: C
Conceptual Explanation: The median is more robust to outliers and skewness than the
mean, making it a better measure of central tendency for skewed data.
3. Which of the following correlation coefficients indicates the strongest linear relationship
between two variables?
A. 0.75
B. 0.01
C. -0.89
D. -0.50
Answer: C
Conceptual Explanation: The strength of a correlation is determined by its absolute value.
0.89 is greater than 0.75, regardless of the negative sign.
, 4. A study reports a 95% confidence interval for the mean weight loss of a group of patients
as (4.5 lbs, 7.5 lbs). What does this interval imply?
A. 95% of patients lost between 4.5 and 7.5 lbs.
B. There is a 95% probability that the next patient will lose weight in this range.
C. We are 95% confident that the true population mean weight loss falls between 4.5 and
7.5 lbs.
D. The sample mean is exactly 6.0 lbs, and all other values are errors.
Answer: C
Conceptual Explanation: A confidence interval provides a range of values that likely
contains the true population parameter based on a certain level of confidence.
5. In a normal distribution, approximately what percentage of data points fall within two
standard deviations of the mean?
A. 68%
B. 99.7%
C. 50%
D. 95%
Answer: D
Conceptual Explanation: According to the Empirical Rule, approximately 95% of data falls
within two standard deviations of the mean in a normal distribution.
STATISTICS COMPREHENSIVE EXAM
1. A researcher is studying the effects of a new hypertension medication. The null hypothesis
states that there is no difference in blood pressure between the treatment and placebo
groups. If the researcher rejects the null hypothesis when it is actually true, what has
occurred?
A. A Type II error
B. A Type I error
C. A correct decision
D. A sampling bias error
Answer: B
Conceptual Explanation: A Type I error occurs when the null hypothesis is rejected even
though it is true (a false positive).
,2. In a dataset representing patient recovery times, the distribution is heavily skewed to the
right. Which measure of central tendency would be most appropriate to describe the
‘average’ recovery time?
A. Mean
B. Mode
C. Median
D. Range
Answer: C
Conceptual Explanation: The median is more robust to outliers and skewness than the
mean, making it a better measure of central tendency for skewed data.
3. Which of the following correlation coefficients indicates the strongest linear relationship
between two variables?
A. 0.75
B. 0.01
C. -0.89
D. -0.50
Answer: C
Conceptual Explanation: The strength of a correlation is determined by its absolute value.
0.89 is greater than 0.75, regardless of the negative sign.
, 4. A study reports a 95% confidence interval for the mean weight loss of a group of patients
as (4.5 lbs, 7.5 lbs). What does this interval imply?
A. 95% of patients lost between 4.5 and 7.5 lbs.
B. There is a 95% probability that the next patient will lose weight in this range.
C. We are 95% confident that the true population mean weight loss falls between 4.5 and
7.5 lbs.
D. The sample mean is exactly 6.0 lbs, and all other values are errors.
Answer: C
Conceptual Explanation: A confidence interval provides a range of values that likely
contains the true population parameter based on a certain level of confidence.
5. In a normal distribution, approximately what percentage of data points fall within two
standard deviations of the mean?
A. 68%
B. 99.7%
C. 50%
D. 95%
Answer: D
Conceptual Explanation: According to the Empirical Rule, approximately 95% of data falls
within two standard deviations of the mean in a normal distribution.
