C784 Applied Healthcare Statistics Practice Exam 2026 |WGU
1. A researcher classifies patients’ smoking status as ‘never smoked’, ‘former
smoker’, or ‘current smoker’. Which level of measurement is being used?
A. Ordinal
B. Nominal
C. Interval
D. Ratio
Answer: A
Rationale: The data is categorized and has a logical order or rank, which defines the
ordinal level of measurement.
2. In a study measuring patient recovery time in days, which level of
measurement is represented?
A. Nominal
B. Ordinal
C. Interval
D. Ratio
Answer: D
Rationale: Recovery time in days has equal intervals and a true zero point (zero days
means no recovery time), making it ratio data.
,3. Which measure of central tendency is most sensitive to extreme outliers in a
healthcare data set?
A. Mode
B. Median
C. Mean
D. Range
Answer: C
Rationale: The mean is calculated using every value in the data set, making it highly
susceptible to being pulled toward extreme values or outliers.
4. A hospital administrator wants to find the most frequent reason for ER visits.
Which measure of central tendency should they use?
A. Mode
B. Median
C. Mean
D. Standard Deviation
Answer: A
Rationale: The mode represents the most frequently occurring value in a data set and is
ideal for categorical data like reasons for visits.
5. What is the relationship between variance and standard deviation?
A. Standard deviation is the square of variance.
B. Variance is the square root of standard deviation.
C. Standard deviation is the square root of variance.
D. They are the same value.
Answer: C
Rationale: Standard deviation is defined as the square root of the variance, providing a
measure of spread in the original units of the data.
, 6. If a data set of patient ages is skewed to the right (positively skewed), which
of the following is typically true?
A. Mean < Median
B. Mode > Mean
C. Mean = Median
D. Mean > Median
Answer: D
Rationale: In a right-skewed distribution, the tail is on the right, and the mean is pulled
toward that tail, making it larger than the median.
7. A z-score of -2.0 for a patient’s cholesterol level indicates that:
A. The level is 2 units below the mean.
B. The level is 2% below the mean.
C. The level is 2 standard deviations below the mean.
D. The level is twice the average.
Answer: C
Rationale: A z-score represents the number of standard deviations a data point is from the
mean; negative indicates it is below the mean.
8. Which of the following describes a Type I error in clinical research?
A. Both B and C.
B. Rejecting a true null hypothesis.
C. Accepting the alternative hypothesis when it is false.
D. Failing to reject a false null hypothesis.
Answer: A
Rationale: A Type I error occurs when the null hypothesis is true, but we reject it (a ‘false
positive’). This is equivalent to accepting the alternative hypothesis when it is false.
1. A researcher classifies patients’ smoking status as ‘never smoked’, ‘former
smoker’, or ‘current smoker’. Which level of measurement is being used?
A. Ordinal
B. Nominal
C. Interval
D. Ratio
Answer: A
Rationale: The data is categorized and has a logical order or rank, which defines the
ordinal level of measurement.
2. In a study measuring patient recovery time in days, which level of
measurement is represented?
A. Nominal
B. Ordinal
C. Interval
D. Ratio
Answer: D
Rationale: Recovery time in days has equal intervals and a true zero point (zero days
means no recovery time), making it ratio data.
,3. Which measure of central tendency is most sensitive to extreme outliers in a
healthcare data set?
A. Mode
B. Median
C. Mean
D. Range
Answer: C
Rationale: The mean is calculated using every value in the data set, making it highly
susceptible to being pulled toward extreme values or outliers.
4. A hospital administrator wants to find the most frequent reason for ER visits.
Which measure of central tendency should they use?
A. Mode
B. Median
C. Mean
D. Standard Deviation
Answer: A
Rationale: The mode represents the most frequently occurring value in a data set and is
ideal for categorical data like reasons for visits.
5. What is the relationship between variance and standard deviation?
A. Standard deviation is the square of variance.
B. Variance is the square root of standard deviation.
C. Standard deviation is the square root of variance.
D. They are the same value.
Answer: C
Rationale: Standard deviation is defined as the square root of the variance, providing a
measure of spread in the original units of the data.
, 6. If a data set of patient ages is skewed to the right (positively skewed), which
of the following is typically true?
A. Mean < Median
B. Mode > Mean
C. Mean = Median
D. Mean > Median
Answer: D
Rationale: In a right-skewed distribution, the tail is on the right, and the mean is pulled
toward that tail, making it larger than the median.
7. A z-score of -2.0 for a patient’s cholesterol level indicates that:
A. The level is 2 units below the mean.
B. The level is 2% below the mean.
C. The level is 2 standard deviations below the mean.
D. The level is twice the average.
Answer: C
Rationale: A z-score represents the number of standard deviations a data point is from the
mean; negative indicates it is below the mean.
8. Which of the following describes a Type I error in clinical research?
A. Both B and C.
B. Rejecting a true null hypothesis.
C. Accepting the alternative hypothesis when it is false.
D. Failing to reject a false null hypothesis.
Answer: A
Rationale: A Type I error occurs when the null hypothesis is true, but we reject it (a ‘false
positive’). This is equivalent to accepting the alternative hypothesis when it is false.
