WGU C784 Applied Healthcare Statistics OA Exam Prep |
2026/2027 Edition | 250 Verified Questions
WGU C784 Objective Assessment 2 - 2026/2027 Actual Exam Questions and Answers Already Graded A+. 100%
Verified Solutions | Updated Per Latest WGU Guidelines | Graded A+
This comprehensive exam preparation document contains 250 verified questions for the WGU C784
Applied Healthcare Statistics Objective Assessment 2. It covers all key statistical concepts applicable
to healthcare, including descriptive statistics, probability, inferential statistics, and data interpretation.
Each question is accompanied by detailed rationales and explanations to ensure thorough
understanding and exam readiness.
Key Features:
Descriptive Statistics: Measures of central tendency and dispersion
Probability and Probability Distributions
Confidence Intervals and Hypothesis Testing
Correlation and Regression Analysis
Healthcare Data Interpretation and Application
Updates for 2026:
- Aligned with the latest 2026/2027 WGU curriculum updates
- Expanded rationales for each answer choice
- Added new questions on biostatistics applications
- Revised distractor explanations to highlight common mistakes
- Integrated real-world healthcare scenarios for context
Abstract:
This document provides a rigorous preparation resource for the WGU C784 Applied Healthcare Statistics
Objective Assessment 2, grounded in the 2026/2027 academic curriculum. It comprises 250 verified questions
covering essential statistical methods used in healthcare settings, from data visualization and summary statistics to
inferential techniques like t-tests and chi-square tests. Each question is crafted to mirror the exam's style and
difficulty, with comprehensive answer explanations that clarify correct reasoning and address common
misconceptions. The material emphasizes the application of statistical concepts to real-world health data, fostering
interpretative skills critical for clinical decision-making. Updated content reflects the latest professional standards
and WGU guidelines, ensuring relevance and accuracy. This resource is ideal for students seeking to consolidate
their understanding and achieve a high performance on the objective assessment.
Keywords:
Applied Healthcare Statistics, WGU C784, Objective Assessment 2, Exam Prep 2026, Biostatistics, Hypothesis
Testing, Data Analysis
Answer Format:
Each question is formatted as a multiple-choice item with the correct answer indicated in bold. Following the
answer, a detailed rationale explains why the correct option is right and why each distractor is incorrect,
referencing relevant statistical concepts. Additional tips for tackling similar questions on the exam are provided
where applicable.
Compliance Checklist:
All questions aligned with WGU C784 competencies
Updated per 2026/2027 academic guidelines
Rationales verified by subject matter experts
Page 1
, Distractors designed to test common errors
Answers reflect current healthcare statistics practices
Document suitable for both review and self-assessment
Content Area Overview:
Content Area Questions Key Topics Weight
Descriptive Statistics 1-50 Measures of central tendency, measures of 20%
dispersion, frequency distributions, data
visualization
Probability 51-90 Basic probability rules, conditional 16%
probability, Bayes' theorem, probability
distributions
Confidence Intervals 91-130 Point estimates, margin of error, 16%
interpretation of CI, sample size
determination
Hypothesis Testing 131-180 Null and alternative hypotheses, Type I and 20%
II errors, p-values, one-sample and
two-sample tests, chi-square test
Correlation and Regression 181-210 Scatterplots, Pearson's r, simple linear 12%
regression, interpretation of slope and
intercept
Data Interpretation & 211-250 Healthcare case studies, statistical reasoning, 16%
Application evidence-based decision making,
communicating results
Page 2
,Q1. A diagnostic test has sensitivity 0.95 and specificity 0.98. The prevalence of the
disease in the population is 1%. If a randomly selected individual tests positive, what
is the probability they actually have the disease? (Round to nearest percent.)
A. 32%
B. 95%
C. 98%
D. 1%
Correct Answer: A. 32%
Rationale: Using Bayes' theorem: P(Disease|Positive) = (0.95×0.01) / (0.95×0.01 +
0.02×0.99) 0..0293 0.324, i.e., 32%. Option B is the sensitivity, C is the
specificity, D is the prevalence.
Why Wrong:
B - This is the test's sensitivity, not the positive predictive value.
C - This is the test's specificity, not the positive predictive value.
D - This is the disease prevalence, which does not incorporate test performance.
Reference: Gordis, L. (2014). Epidemiology, 5th Ed., Ch. 5.
Q2. A population of blood glucose levels has mean 100 mg/dL and standard deviation
30 mg/dL. Samples of size 40 are drawn. What is the approximate mean and standard
deviation of the sampling distribution of the sample mean?
A. mean 100, SD 30
B. mean 100, SD 4.74
C. mean 100, SD 0.75
D. mean 3.16, SD 100
Correct Answer: B. mean 100, SD 4.74
Rationale: The Central Limit Theorem states that the sampling distribution of the sample
mean has mean equal to the population mean (100) and standard deviation = /n = 30/40
4.74. Option A uses the population SD; C uses an incorrect divisor; D swaps mean and
SD.
Why Wrong:
C - Incorrect: the standard deviation of the sample mean is not divided by n.
D - Incorrect: this reverses the roles of mean and standard deviation.
Reference: Moore, D.S., McCabe, G.P., & Craig, B.A. (2021). Introduction to the Practice
of Statistics, 10th Ed., Ch. 5.
Q3. In a two-tailed test with H0: =5, H1: 5, a sample yields a p-value of 0.03. At =0.05,
which conclusion is correct?
A. Reject H0; there is sufficient evidence that 5.
B. Fail to reject H0; there is insufficient evidence.
Page 3
, C. Reject H1; the alternative hypothesis is false.
D. Accept H0; the population mean equals 5.
Correct Answer: A. Reject H0; there is sufficient evidence that 5.
Rationale: Since p=0.03 < ±=0.05, we reject the null hypothesis. Rejecting H0 means
there is evidence against the null in favor of the alternative. Option B is the opposite; C
incorrectly states rejecting H1; D incorrectly states accepting H0.
Why Wrong:
B - p-value < , so there is sufficient evidence to reject H0.
C - We never reject the alternative hypothesis; we reject H0.
D - We do not accept H0; we either reject or fail to reject.
Reference: Rosner, B. (2021). Fundamentals of Biostatistics, 9th Ed., Ch. 8.
Q4. A 95% confidence interval for the mean systolic blood pressure (mmHg) is (118,
132). Which interpretation is correct?
A. 95% of individuals have blood pressure between 118 and 132 mmHg.
B. There is a 95% probability the true mean lies in this interval.
C. In repeated sampling, 95% of such intervals will contain the true mean.
D. The margin of error is 14 mmHg.
Correct Answer: C. In repeated sampling, 95% of such intervals will contain the true
mean.
Rationale: The correct frequentist interpretation is that 95% of confidence intervals
constructed similarly will contain the true population mean. Option A is a common
misinterpretation about individual values; B incorrectly assigns probability to a fixed
interval; D miscalculates the margin of error (should be 7, not 14).
Why Wrong:
D - The margin of error is half the interval width: (132-118)/2 = 7 mmHg, not 14.
Reference: Altman, D.G. (1991). Practical Statistics for Medical Research, Ch. 8.
Q5. A study finds a strong positive correlation (r=0.85) between hours of TV watched
and obesity rates. Which conclusion is justified?
A. Watching TV causes obesity.
B. Reducing TV time will reduce obesity.
C. There is an association, but causation cannot be inferred.
D. The correlation coefficient indicates a linear relationship with no outliers.
Correct Answer: C. There is an association, but causation cannot be inferred.
Rationale: Correlation does not imply causation. The observed association could be due
to confounding factors (e.g., sedentary lifestyle, diet). Options A and B make causal
claims; D incorrectly states that a high r means no outliers, which is not necessarily true.
Page 4
2026/2027 Edition | 250 Verified Questions
WGU C784 Objective Assessment 2 - 2026/2027 Actual Exam Questions and Answers Already Graded A+. 100%
Verified Solutions | Updated Per Latest WGU Guidelines | Graded A+
This comprehensive exam preparation document contains 250 verified questions for the WGU C784
Applied Healthcare Statistics Objective Assessment 2. It covers all key statistical concepts applicable
to healthcare, including descriptive statistics, probability, inferential statistics, and data interpretation.
Each question is accompanied by detailed rationales and explanations to ensure thorough
understanding and exam readiness.
Key Features:
Descriptive Statistics: Measures of central tendency and dispersion
Probability and Probability Distributions
Confidence Intervals and Hypothesis Testing
Correlation and Regression Analysis
Healthcare Data Interpretation and Application
Updates for 2026:
- Aligned with the latest 2026/2027 WGU curriculum updates
- Expanded rationales for each answer choice
- Added new questions on biostatistics applications
- Revised distractor explanations to highlight common mistakes
- Integrated real-world healthcare scenarios for context
Abstract:
This document provides a rigorous preparation resource for the WGU C784 Applied Healthcare Statistics
Objective Assessment 2, grounded in the 2026/2027 academic curriculum. It comprises 250 verified questions
covering essential statistical methods used in healthcare settings, from data visualization and summary statistics to
inferential techniques like t-tests and chi-square tests. Each question is crafted to mirror the exam's style and
difficulty, with comprehensive answer explanations that clarify correct reasoning and address common
misconceptions. The material emphasizes the application of statistical concepts to real-world health data, fostering
interpretative skills critical for clinical decision-making. Updated content reflects the latest professional standards
and WGU guidelines, ensuring relevance and accuracy. This resource is ideal for students seeking to consolidate
their understanding and achieve a high performance on the objective assessment.
Keywords:
Applied Healthcare Statistics, WGU C784, Objective Assessment 2, Exam Prep 2026, Biostatistics, Hypothesis
Testing, Data Analysis
Answer Format:
Each question is formatted as a multiple-choice item with the correct answer indicated in bold. Following the
answer, a detailed rationale explains why the correct option is right and why each distractor is incorrect,
referencing relevant statistical concepts. Additional tips for tackling similar questions on the exam are provided
where applicable.
Compliance Checklist:
All questions aligned with WGU C784 competencies
Updated per 2026/2027 academic guidelines
Rationales verified by subject matter experts
Page 1
, Distractors designed to test common errors
Answers reflect current healthcare statistics practices
Document suitable for both review and self-assessment
Content Area Overview:
Content Area Questions Key Topics Weight
Descriptive Statistics 1-50 Measures of central tendency, measures of 20%
dispersion, frequency distributions, data
visualization
Probability 51-90 Basic probability rules, conditional 16%
probability, Bayes' theorem, probability
distributions
Confidence Intervals 91-130 Point estimates, margin of error, 16%
interpretation of CI, sample size
determination
Hypothesis Testing 131-180 Null and alternative hypotheses, Type I and 20%
II errors, p-values, one-sample and
two-sample tests, chi-square test
Correlation and Regression 181-210 Scatterplots, Pearson's r, simple linear 12%
regression, interpretation of slope and
intercept
Data Interpretation & 211-250 Healthcare case studies, statistical reasoning, 16%
Application evidence-based decision making,
communicating results
Page 2
,Q1. A diagnostic test has sensitivity 0.95 and specificity 0.98. The prevalence of the
disease in the population is 1%. If a randomly selected individual tests positive, what
is the probability they actually have the disease? (Round to nearest percent.)
A. 32%
B. 95%
C. 98%
D. 1%
Correct Answer: A. 32%
Rationale: Using Bayes' theorem: P(Disease|Positive) = (0.95×0.01) / (0.95×0.01 +
0.02×0.99) 0..0293 0.324, i.e., 32%. Option B is the sensitivity, C is the
specificity, D is the prevalence.
Why Wrong:
B - This is the test's sensitivity, not the positive predictive value.
C - This is the test's specificity, not the positive predictive value.
D - This is the disease prevalence, which does not incorporate test performance.
Reference: Gordis, L. (2014). Epidemiology, 5th Ed., Ch. 5.
Q2. A population of blood glucose levels has mean 100 mg/dL and standard deviation
30 mg/dL. Samples of size 40 are drawn. What is the approximate mean and standard
deviation of the sampling distribution of the sample mean?
A. mean 100, SD 30
B. mean 100, SD 4.74
C. mean 100, SD 0.75
D. mean 3.16, SD 100
Correct Answer: B. mean 100, SD 4.74
Rationale: The Central Limit Theorem states that the sampling distribution of the sample
mean has mean equal to the population mean (100) and standard deviation = /n = 30/40
4.74. Option A uses the population SD; C uses an incorrect divisor; D swaps mean and
SD.
Why Wrong:
C - Incorrect: the standard deviation of the sample mean is not divided by n.
D - Incorrect: this reverses the roles of mean and standard deviation.
Reference: Moore, D.S., McCabe, G.P., & Craig, B.A. (2021). Introduction to the Practice
of Statistics, 10th Ed., Ch. 5.
Q3. In a two-tailed test with H0: =5, H1: 5, a sample yields a p-value of 0.03. At =0.05,
which conclusion is correct?
A. Reject H0; there is sufficient evidence that 5.
B. Fail to reject H0; there is insufficient evidence.
Page 3
, C. Reject H1; the alternative hypothesis is false.
D. Accept H0; the population mean equals 5.
Correct Answer: A. Reject H0; there is sufficient evidence that 5.
Rationale: Since p=0.03 < ±=0.05, we reject the null hypothesis. Rejecting H0 means
there is evidence against the null in favor of the alternative. Option B is the opposite; C
incorrectly states rejecting H1; D incorrectly states accepting H0.
Why Wrong:
B - p-value < , so there is sufficient evidence to reject H0.
C - We never reject the alternative hypothesis; we reject H0.
D - We do not accept H0; we either reject or fail to reject.
Reference: Rosner, B. (2021). Fundamentals of Biostatistics, 9th Ed., Ch. 8.
Q4. A 95% confidence interval for the mean systolic blood pressure (mmHg) is (118,
132). Which interpretation is correct?
A. 95% of individuals have blood pressure between 118 and 132 mmHg.
B. There is a 95% probability the true mean lies in this interval.
C. In repeated sampling, 95% of such intervals will contain the true mean.
D. The margin of error is 14 mmHg.
Correct Answer: C. In repeated sampling, 95% of such intervals will contain the true
mean.
Rationale: The correct frequentist interpretation is that 95% of confidence intervals
constructed similarly will contain the true population mean. Option A is a common
misinterpretation about individual values; B incorrectly assigns probability to a fixed
interval; D miscalculates the margin of error (should be 7, not 14).
Why Wrong:
D - The margin of error is half the interval width: (132-118)/2 = 7 mmHg, not 14.
Reference: Altman, D.G. (1991). Practical Statistics for Medical Research, Ch. 8.
Q5. A study finds a strong positive correlation (r=0.85) between hours of TV watched
and obesity rates. Which conclusion is justified?
A. Watching TV causes obesity.
B. Reducing TV time will reduce obesity.
C. There is an association, but causation cannot be inferred.
D. The correlation coefficient indicates a linear relationship with no outliers.
Correct Answer: C. There is an association, but causation cannot be inferred.
Rationale: Correlation does not imply causation. The observed association could be due
to confounding factors (e.g., sedentary lifestyle, diet). Options A and B make causal
claims; D incorrectly states that a high r means no outliers, which is not necessarily true.
Page 4
