NUR 350 | NUR350 Exam 3: Research in Nursing -
CWCU Updated and Latest Questions and Correct
Answers with Rationale
1. A researcher is assessing the consistency of a new survey tool by administering it twice to
the same group of participants over two weeks. Which type of reliability is being evaluated?
A. Test-retest reliability
B. Inter-rater reliability
C. Internal consistency
D. Content validity
Correct Answer: A
Rationale: Test-retest reliability measures the stability of an instrument over time by
comparing scores from two different administrations. The researcher is looking for high
correlation between the first and second sets of results to ensure the tool produces stable
data. Other forms of reliability, like internal consistency, focus on how items within the tool
relate to one another rather than stability over time. Validity measures differ because they
focus on whether the tool measures what it is supposed to measure. This process is
essential in nursing research to ensure that patient assessments are dependable across
different time points.
2. When a researcher conducts a study and concludes that a treatment is effective when in
reality it is not, what has occurred?
A. Type I error
B. Type II error
C. Standard error of the mean
D. Sampling bias
Correct Answer: A
Rationale: A Type I error occurs when the null hypothesis is rejected even though it is
actually true. This is often referred to as a false positive result in clinical settings.
Conversely, a Type II error involves failing to find a difference that actually exists between
groups. Statistical significance levels, like alpha, are set to minimize the risk of making this
specific error. For nurse researchers, avoiding Type I errors is critical because it prevents
the adoption of ineffective or potentially harmful interventions.
3. A nursing study reports a p-value of 0.02. How should the nurse researcher interpret this
result?
A. The result is not statistically significant because it is less than 0.05.
,B. The null hypothesis should be accepted because the p-value is low.
C. There is a 2% chance that the results are due to random chance.
D. The study has reached a 98% probability of being clinically significant.
Correct Answer: C
Rationale: The p-value represents the probability that the observed results occurred by
chance alone if the null hypothesis were true. A p-value of 0.02 is less than the standard
threshold of 0.05, indicating statistical significance. This leads the researcher to reject the
null hypothesis in favor of the alternative hypothesis. However, statistical significance does
not always equate to clinical significance or the importance of the effect in practice. Nurses
must look at both the p-value and the clinical context to determine if a change in practice is
warranted.
4. Which level of measurement provides the most information and includes an absolute zero
point?
A. Ratio
B. Ordinal
C. Interval
D. Nominal
Correct Answer: A
Rationale: Ratio data represents the highest level of measurement because it contains all
the properties of lower levels plus an absolute zero. Examples in nursing include weight,
height, and blood pressure readings. Nominal data only categorizes, while ordinal data
ranks, and interval data has equal distances but no true zero. Because ratio data has a true
zero, researchers can perform complex mathematical operations like multiplication and
division. Identifying the level of measurement is the first step in selecting the appropriate
statistical test for data analysis.
5. In a normal distribution, approximately what percentage of scores fall within one standard
deviation of the mean?
A. 34%
B. 50%
C. 95%
D. 68%
Correct Answer: D
Rationale: In a bell-shaped or normal distribution, the standard deviation describes the
spread of data around the mean. The empirical rule states that 68% of data points fall
, within one standard deviation above or below the average. Moving to two standard
deviations accounts for approximately 95% of the data in the set. This statistical principle
allows researchers to understand how much variation exists within a sample population.
Understanding these distributions helps nurses evaluate whether a specific patient’s data is
typical or an outlier compared to a group.
6. A researcher calculates a Cronbach’s alpha of 0.85 for a new pain assessment tool. What
does this value indicate?
A. The tool has poor internal consistency.
B. The tool has good internal consistency.
C. The tool is valid but not reliable.
D. The tool has a high level of observer bias.
Correct Answer: B
Rationale: Cronbach’s alpha is a statistical measure used to determine the internal
consistency or reliability of a multi-item scale. A value of 0.85 is generally considered good
to excellent, indicating that the items in the tool are highly correlated. Values below 0.70
are usually seen as questionable for new instruments in research settings. High internal
consistency ensures that all parts of the tool are measuring the same underlying construct.
For clinicians, using a tool with high reliability means the assessment of the patient is more
likely to be accurate.
7. Which statistical test is most appropriate for comparing the mean scores of two
independent groups?
A. Pearson correlation
B. Chi-square test
C. ANOVA
D. Independent t-test
Correct Answer: D
Rationale: The independent t-test is used to determine if there is a significant difference
between the means of two unrelated groups. For example, it might compare the recovery
times of patients receiving a new drug versus those receiving a placebo. A Chi-square test
would be used for categorical data, while a correlation measures the relationship between
two variables. If there were more than two groups to compare, an ANOVA would be the
correct choice. Nurses use these tests to determine if a new nursing intervention is truly
better than standard care.
8. Construct validity is best described as:
A. The degree to which an instrument covers all domains of a concept.
B. The degree to which an instrument measures the intended theoretical framework.
CWCU Updated and Latest Questions and Correct
Answers with Rationale
1. A researcher is assessing the consistency of a new survey tool by administering it twice to
the same group of participants over two weeks. Which type of reliability is being evaluated?
A. Test-retest reliability
B. Inter-rater reliability
C. Internal consistency
D. Content validity
Correct Answer: A
Rationale: Test-retest reliability measures the stability of an instrument over time by
comparing scores from two different administrations. The researcher is looking for high
correlation between the first and second sets of results to ensure the tool produces stable
data. Other forms of reliability, like internal consistency, focus on how items within the tool
relate to one another rather than stability over time. Validity measures differ because they
focus on whether the tool measures what it is supposed to measure. This process is
essential in nursing research to ensure that patient assessments are dependable across
different time points.
2. When a researcher conducts a study and concludes that a treatment is effective when in
reality it is not, what has occurred?
A. Type I error
B. Type II error
C. Standard error of the mean
D. Sampling bias
Correct Answer: A
Rationale: A Type I error occurs when the null hypothesis is rejected even though it is
actually true. This is often referred to as a false positive result in clinical settings.
Conversely, a Type II error involves failing to find a difference that actually exists between
groups. Statistical significance levels, like alpha, are set to minimize the risk of making this
specific error. For nurse researchers, avoiding Type I errors is critical because it prevents
the adoption of ineffective or potentially harmful interventions.
3. A nursing study reports a p-value of 0.02. How should the nurse researcher interpret this
result?
A. The result is not statistically significant because it is less than 0.05.
,B. The null hypothesis should be accepted because the p-value is low.
C. There is a 2% chance that the results are due to random chance.
D. The study has reached a 98% probability of being clinically significant.
Correct Answer: C
Rationale: The p-value represents the probability that the observed results occurred by
chance alone if the null hypothesis were true. A p-value of 0.02 is less than the standard
threshold of 0.05, indicating statistical significance. This leads the researcher to reject the
null hypothesis in favor of the alternative hypothesis. However, statistical significance does
not always equate to clinical significance or the importance of the effect in practice. Nurses
must look at both the p-value and the clinical context to determine if a change in practice is
warranted.
4. Which level of measurement provides the most information and includes an absolute zero
point?
A. Ratio
B. Ordinal
C. Interval
D. Nominal
Correct Answer: A
Rationale: Ratio data represents the highest level of measurement because it contains all
the properties of lower levels plus an absolute zero. Examples in nursing include weight,
height, and blood pressure readings. Nominal data only categorizes, while ordinal data
ranks, and interval data has equal distances but no true zero. Because ratio data has a true
zero, researchers can perform complex mathematical operations like multiplication and
division. Identifying the level of measurement is the first step in selecting the appropriate
statistical test for data analysis.
5. In a normal distribution, approximately what percentage of scores fall within one standard
deviation of the mean?
A. 34%
B. 50%
C. 95%
D. 68%
Correct Answer: D
Rationale: In a bell-shaped or normal distribution, the standard deviation describes the
spread of data around the mean. The empirical rule states that 68% of data points fall
, within one standard deviation above or below the average. Moving to two standard
deviations accounts for approximately 95% of the data in the set. This statistical principle
allows researchers to understand how much variation exists within a sample population.
Understanding these distributions helps nurses evaluate whether a specific patient’s data is
typical or an outlier compared to a group.
6. A researcher calculates a Cronbach’s alpha of 0.85 for a new pain assessment tool. What
does this value indicate?
A. The tool has poor internal consistency.
B. The tool has good internal consistency.
C. The tool is valid but not reliable.
D. The tool has a high level of observer bias.
Correct Answer: B
Rationale: Cronbach’s alpha is a statistical measure used to determine the internal
consistency or reliability of a multi-item scale. A value of 0.85 is generally considered good
to excellent, indicating that the items in the tool are highly correlated. Values below 0.70
are usually seen as questionable for new instruments in research settings. High internal
consistency ensures that all parts of the tool are measuring the same underlying construct.
For clinicians, using a tool with high reliability means the assessment of the patient is more
likely to be accurate.
7. Which statistical test is most appropriate for comparing the mean scores of two
independent groups?
A. Pearson correlation
B. Chi-square test
C. ANOVA
D. Independent t-test
Correct Answer: D
Rationale: The independent t-test is used to determine if there is a significant difference
between the means of two unrelated groups. For example, it might compare the recovery
times of patients receiving a new drug versus those receiving a placebo. A Chi-square test
would be used for categorical data, while a correlation measures the relationship between
two variables. If there were more than two groups to compare, an ANOVA would be the
correct choice. Nurses use these tests to determine if a new nursing intervention is truly
better than standard care.
8. Construct validity is best described as:
A. The degree to which an instrument covers all domains of a concept.
B. The degree to which an instrument measures the intended theoretical framework.
