WGU C784 Applied Healthcare Statistics Objective
Assessment – C784 Study Guide, Original Practice
Questions & Answers, Objective Assessment
Preparation, Comprehensive WGU Statistics Review,
Probability, Descriptive Statistics, Regression,
Correlation, Algebra, Data Interpretation &
Healthcare Statistics
Question 1: A researcher is studying the average recovery time in days for
patients after a specific surgery. The recovery times for a sample of 10 patients
are as follows: 12, 15, 18, 14, 16, 20, 13, 17, 15, and 19. What is the median
recovery time for this sample?
A. 15.5
B. 15.0
C. 16.0
D. 15.9
CORRECT ANSWER: A. 15.5
Rationale: To find the median, the data must first be ordered from least to greatest: 12,
13, 14, 15, 15, 16, 17, 18, 19, 20. Since there is an even number of observations (n=10),
the median is the average of the 5th and 6th values. The 5th value is 15 and the 6th
value is 16. The average is (15+16)/2 = 15.5.
Question 2: A public health official is calculating the birth rate for a city. The
city has a population of 450,000 and there were 4,950 live births in the year.
What is the birth rate per 1,000 people?
A. 11.0
B. 9.1
C. 10.8
D. 12.5
CORRECT ANSWER: A. 11.0
Rationale: The birth rate per 1,000 is calculated as (Number of live births / Total
population) * 1,000. (4,,000) * 1,000 = 0.011 * 1,000 = 11.0 births per 1,000
people.
Question 3: In a clinical trial, 120 patients are given a new treatment. If 30 of
these patients experience a specific side effect, what is the relative frequency
of the side effect?
A. 0.20
B. 0.25
C. 0.30
D. 0.35
CORRECT ANSWER: B. 0.25
,WGU C784 Applied Healthcare Statistics Objective
Assessment – C784 Study Guide, Original Practice
Questions & Answers, Objective Assessment
Preparation, Comprehensive WGU Statistics Review,
Probability, Descriptive Statistics, Regression,
Correlation, Algebra, Data Interpretation &
Healthcare Statistics
Rationale: Relative frequency is calculated by dividing the frequency of the event by the
total number of observations. Therefore, = 0.25.
Question 4: A data set has a mean of 85 and a median of 82. What is the most
likely shape of the distribution?
A. Symmetrical
B. Positively skewed (right-skewed)
C. Negatively skewed (left-skewed)
D. Bimodal
CORRECT ANSWER: C. Negatively skewed (left-skewed)
Rationale: In a negatively skewed (left-skewed) distribution, the mean is typically less
than the median due to the presence of low outliers. Here, the mean (85) is greater than
the median (82), which indicates positive skew. A re-evaluation shows the mean is pulled
towards the tail on the right. Wait, if the mean > median, it is positively skewed (right-
skewed). Let's correct: If Mean (85) > Median (82), the tail is on the right. Therefore, the
correct answer is B. I will adjust the answer.
Question 4 (Corrected): A data set has a mean of 85 and a median of 82. What
is the most likely shape of the distribution?
A. Symmetrical
B. Positively skewed (right-skewed)
C. Negatively skewed (left-skewed)
D. Bimodal
CORRECT ANSWER: B. Positively skewed (right-skewed)
Rationale: The mean is more sensitive to extreme values than the median. When the
mean is greater than the median, it indicates that the distribution has a tail extending
towards higher values (to the right). This is known as a positively skewed or right-
skewed distribution.
Question 5: What is the primary purpose of using a stem-and-leaf plot instead
of a standard frequency distribution table?
A. To show the shape of the distribution while retaining the original data values.
B. To completely hide the individual data points for privacy.
C. To summarize categorical data more effectively.
D. To calculate the standard deviation directly from the display.
,WGU C784 Applied Healthcare Statistics Objective
Assessment – C784 Study Guide, Original Practice
Questions & Answers, Objective Assessment
Preparation, Comprehensive WGU Statistics Review,
Probability, Descriptive Statistics, Regression,
Correlation, Algebra, Data Interpretation &
Healthcare Statistics
CORRECT ANSWER: A. To show the shape of the distribution while retaining
the original data values.
Rationale: A stem-and-leaf plot provides a visual representation of the data distribution
(like a histogram) but has the advantage of displaying the actual individual data values,
thus preserving the original data points for further analysis.
Question 6: A hospital administrator has mortality data for two units. Unit A
has a mortality rate of 2.5% and Unit B has a rate of 3.0%. If Unit A had 2,000
patients and Unit B had 1,000 patients, what is the overall mortality rate for
both units combined?
A. 2.75%
B. 2.67%
C. 2.83%
D. 2.50%
CORRECT ANSWER: B. 2.67%
Rationale: First, find the number of deaths in each unit. Unit A: 0.025 * 2,000 = 50
deaths. Unit B: 0.03 * 1,000 = 30 deaths. Total deaths = 80. Total patients = 3,000.
Overall rate = (,000) * 100 = 2.666...%, which rounds to 2.67%.
Question 7: Which measure of central tendency is most appropriate for a
dataset containing extreme outliers, such as the cost of hospital stays where
most are around $5,000 but a few are over $100,000?
A. Mean
B. Median
C. Mode
D. Range
CORRECT ANSWER: B. Median
Rationale: The median is resistant to outliers. Extreme values can drastically pull the
mean in one direction, making it an unrepresentative measure of the "typical" value. The
median, being the middle value, remains stable regardless of how extreme the high or
low values are.
Question 8: A physician is studying the relationship between patient age and
blood pressure. He records the ages and systolic blood pressures of 50
patients. Which type of graph is best for visualizing this relationship?
, WGU C784 Applied Healthcare Statistics Objective
Assessment – C784 Study Guide, Original Practice
Questions & Answers, Objective Assessment
Preparation, Comprehensive WGU Statistics Review,
Probability, Descriptive Statistics, Regression,
Correlation, Algebra, Data Interpretation &
Healthcare Statistics
A. Bar chart
B. Pie chart
C. Scatter plot
D. Histogram
CORRECT ANSWER: C. Scatter plot
Rationale: A scatter plot is used to display the relationship between two quantitative
variables. In this case, age and blood pressure are both continuous numerical variables,
making a scatter plot the most appropriate choice to see if there is a correlation or
trend.
Question 9: A study reports that the standard deviation of cholesterol levels in
a group of 100 patients is 25 mg/dL. What does this measure of variability
indicate?
A. The average cholesterol level in the group is 25 mg/dL.
B. The cholesterol levels are typically 25 mg/dL above or below the mean.
C. The highest cholesterol level is 25 mg/dL more than the lowest.
D. The middle 50% of cholesterol levels are within 25 mg/dL of each other.
CORRECT ANSWER: B. The cholesterol levels are typically 25 mg/dL above or
below the mean.
Rationale: The standard deviation is a measure of the average distance (or spread) of
the individual data points from the mean. A standard deviation of 25 mg/dL indicates
that, on average, the patients' cholesterol levels deviate from the sample mean by about
25 mg/dL.
Question 10: What is the mode of the following dataset representing the
number of medications taken by patients in a clinic? Data: 1, 2, 2, 3, 4, 4, 4, 5,
6, 6
A. 2
B. 3
C. 4
D. 6
CORRECT ANSWER: C. 4
Assessment – C784 Study Guide, Original Practice
Questions & Answers, Objective Assessment
Preparation, Comprehensive WGU Statistics Review,
Probability, Descriptive Statistics, Regression,
Correlation, Algebra, Data Interpretation &
Healthcare Statistics
Question 1: A researcher is studying the average recovery time in days for
patients after a specific surgery. The recovery times for a sample of 10 patients
are as follows: 12, 15, 18, 14, 16, 20, 13, 17, 15, and 19. What is the median
recovery time for this sample?
A. 15.5
B. 15.0
C. 16.0
D. 15.9
CORRECT ANSWER: A. 15.5
Rationale: To find the median, the data must first be ordered from least to greatest: 12,
13, 14, 15, 15, 16, 17, 18, 19, 20. Since there is an even number of observations (n=10),
the median is the average of the 5th and 6th values. The 5th value is 15 and the 6th
value is 16. The average is (15+16)/2 = 15.5.
Question 2: A public health official is calculating the birth rate for a city. The
city has a population of 450,000 and there were 4,950 live births in the year.
What is the birth rate per 1,000 people?
A. 11.0
B. 9.1
C. 10.8
D. 12.5
CORRECT ANSWER: A. 11.0
Rationale: The birth rate per 1,000 is calculated as (Number of live births / Total
population) * 1,000. (4,,000) * 1,000 = 0.011 * 1,000 = 11.0 births per 1,000
people.
Question 3: In a clinical trial, 120 patients are given a new treatment. If 30 of
these patients experience a specific side effect, what is the relative frequency
of the side effect?
A. 0.20
B. 0.25
C. 0.30
D. 0.35
CORRECT ANSWER: B. 0.25
,WGU C784 Applied Healthcare Statistics Objective
Assessment – C784 Study Guide, Original Practice
Questions & Answers, Objective Assessment
Preparation, Comprehensive WGU Statistics Review,
Probability, Descriptive Statistics, Regression,
Correlation, Algebra, Data Interpretation &
Healthcare Statistics
Rationale: Relative frequency is calculated by dividing the frequency of the event by the
total number of observations. Therefore, = 0.25.
Question 4: A data set has a mean of 85 and a median of 82. What is the most
likely shape of the distribution?
A. Symmetrical
B. Positively skewed (right-skewed)
C. Negatively skewed (left-skewed)
D. Bimodal
CORRECT ANSWER: C. Negatively skewed (left-skewed)
Rationale: In a negatively skewed (left-skewed) distribution, the mean is typically less
than the median due to the presence of low outliers. Here, the mean (85) is greater than
the median (82), which indicates positive skew. A re-evaluation shows the mean is pulled
towards the tail on the right. Wait, if the mean > median, it is positively skewed (right-
skewed). Let's correct: If Mean (85) > Median (82), the tail is on the right. Therefore, the
correct answer is B. I will adjust the answer.
Question 4 (Corrected): A data set has a mean of 85 and a median of 82. What
is the most likely shape of the distribution?
A. Symmetrical
B. Positively skewed (right-skewed)
C. Negatively skewed (left-skewed)
D. Bimodal
CORRECT ANSWER: B. Positively skewed (right-skewed)
Rationale: The mean is more sensitive to extreme values than the median. When the
mean is greater than the median, it indicates that the distribution has a tail extending
towards higher values (to the right). This is known as a positively skewed or right-
skewed distribution.
Question 5: What is the primary purpose of using a stem-and-leaf plot instead
of a standard frequency distribution table?
A. To show the shape of the distribution while retaining the original data values.
B. To completely hide the individual data points for privacy.
C. To summarize categorical data more effectively.
D. To calculate the standard deviation directly from the display.
,WGU C784 Applied Healthcare Statistics Objective
Assessment – C784 Study Guide, Original Practice
Questions & Answers, Objective Assessment
Preparation, Comprehensive WGU Statistics Review,
Probability, Descriptive Statistics, Regression,
Correlation, Algebra, Data Interpretation &
Healthcare Statistics
CORRECT ANSWER: A. To show the shape of the distribution while retaining
the original data values.
Rationale: A stem-and-leaf plot provides a visual representation of the data distribution
(like a histogram) but has the advantage of displaying the actual individual data values,
thus preserving the original data points for further analysis.
Question 6: A hospital administrator has mortality data for two units. Unit A
has a mortality rate of 2.5% and Unit B has a rate of 3.0%. If Unit A had 2,000
patients and Unit B had 1,000 patients, what is the overall mortality rate for
both units combined?
A. 2.75%
B. 2.67%
C. 2.83%
D. 2.50%
CORRECT ANSWER: B. 2.67%
Rationale: First, find the number of deaths in each unit. Unit A: 0.025 * 2,000 = 50
deaths. Unit B: 0.03 * 1,000 = 30 deaths. Total deaths = 80. Total patients = 3,000.
Overall rate = (,000) * 100 = 2.666...%, which rounds to 2.67%.
Question 7: Which measure of central tendency is most appropriate for a
dataset containing extreme outliers, such as the cost of hospital stays where
most are around $5,000 but a few are over $100,000?
A. Mean
B. Median
C. Mode
D. Range
CORRECT ANSWER: B. Median
Rationale: The median is resistant to outliers. Extreme values can drastically pull the
mean in one direction, making it an unrepresentative measure of the "typical" value. The
median, being the middle value, remains stable regardless of how extreme the high or
low values are.
Question 8: A physician is studying the relationship between patient age and
blood pressure. He records the ages and systolic blood pressures of 50
patients. Which type of graph is best for visualizing this relationship?
, WGU C784 Applied Healthcare Statistics Objective
Assessment – C784 Study Guide, Original Practice
Questions & Answers, Objective Assessment
Preparation, Comprehensive WGU Statistics Review,
Probability, Descriptive Statistics, Regression,
Correlation, Algebra, Data Interpretation &
Healthcare Statistics
A. Bar chart
B. Pie chart
C. Scatter plot
D. Histogram
CORRECT ANSWER: C. Scatter plot
Rationale: A scatter plot is used to display the relationship between two quantitative
variables. In this case, age and blood pressure are both continuous numerical variables,
making a scatter plot the most appropriate choice to see if there is a correlation or
trend.
Question 9: A study reports that the standard deviation of cholesterol levels in
a group of 100 patients is 25 mg/dL. What does this measure of variability
indicate?
A. The average cholesterol level in the group is 25 mg/dL.
B. The cholesterol levels are typically 25 mg/dL above or below the mean.
C. The highest cholesterol level is 25 mg/dL more than the lowest.
D. The middle 50% of cholesterol levels are within 25 mg/dL of each other.
CORRECT ANSWER: B. The cholesterol levels are typically 25 mg/dL above or
below the mean.
Rationale: The standard deviation is a measure of the average distance (or spread) of
the individual data points from the mean. A standard deviation of 25 mg/dL indicates
that, on average, the patients' cholesterol levels deviate from the sample mean by about
25 mg/dL.
Question 10: What is the mode of the following dataset representing the
number of medications taken by patients in a clinic? Data: 1, 2, 2, 3, 4, 4, 4, 5,
6, 6
A. 2
B. 3
C. 4
D. 6
CORRECT ANSWER: C. 4
