Non-Parametric Tests for Nursing: Chi-Square, Mann-Whitney U, Kruskal-Wallis

Question 1

Which of the following is a feature of a non-parametric test?

Accepted Answer

Can be used with ordinal or nominal data

Answer

Assumes data is normally distributed

Answer

Requires a large sample size

Answer

Requires known population variance

Question 2

Which of the following is a crucial assumption for the validity of non-parametric tests?

Accepted Answer

Independent observations

Answer

Normally distributed data

Answer

Large sample size

Answer

Continuous variables

Question 3

Which of the following is NOT an assumption of the chi-square test?

Accepted Answer

The data must be normally distributed.

Answer

The data must be categorical.

Answer

The expected frequencies must be at least 5 for at least 80% of the cells.

Answer

The data must be independent.

Question 4

What is the purpose of the Mann-Whitney U test?

Accepted Answer

To compare two independent samples on an ordinal or continuous scale.

Answer

To compare two dependent samples on a continuous scale.

Answer

To test for significant differences in proportions between groups.

Answer

To test for the association between two categorical variables.

Question 5

Which statistic is used to test for differences among three or more independent groups on an ordinal or continuous scale?

Accepted Answer

Kruskal-Wallis statistic

Answer

Chi-square statistic

Answer

Mann-Whitney U statistic

Answer

Z-score

Question 6

A nurse researcher wants to determine if there is a difference in the anxiety levels of patients before and after a nursing intervention. Which non-parametric test would be appropriate?

Accepted Answer

Wilcoxon signed-rank test

Answer

Chi-square test

Answer

Mann-Whitney U test

Answer

Kruskal-Wallis test

Question 7

What is the critical value for a chi-square test with 5 degrees of freedom at an alpha level of 0.05?

Accepted Answer

11.07

Answer

12.59

Answer

15.09

Answer

16.92

Question 8

Which of the following is a disadvantage of using non-parametric tests?

Accepted Answer

They can be less powerful than parametric tests when the assumptions of the parametric tests are met.

Answer

They do not require the data to be normally distributed.

Answer

They are not as widely used as parametric tests.

Answer

They can only be used for small sample sizes.

Question 9

What is the null hypothesis for the Kruskal-Wallis test?

Accepted Answer

The medians of the groups are equal.

Answer

The means of the groups are equal.

Answer

The variances of the groups are equal.

Answer

The proportions of the groups are equal.

Question 10

Which of the following is NOT a requirement for using the chi-square test?

Accepted Answer

The sample size should be large enough.

Answer

The data should be in the form of nominal or ordinal variables.

Answer

The observations should be independent.

Answer

The expected frequencies should be at least 5 for each cell.

Question 11

The Mann-Whitney U test is used to compare:

Accepted Answer

The medians of two independent groups of ordinal data.

Answer

The means of two independent groups of interval data.

Answer

The proportions of two independent groups of nominal data.

Answer

The variances of two independent groups of interval data.

Question 12

The Kruskal-Wallis test is the non-parametric equivalent of which parametric test?

Accepted Answer

ANOVA

Answer

t-test

Answer

Regression

Answer

Correlation

Question 13

A potential limitation of non-parametric tests is their:

Accepted Answer

Reduced power compared to parametric tests.

Answer

Requirement for large sample sizes.

Answer

Inability to test relationships between variables.

Answer

Unsuitability for normally distributed data.

Question 14

To compare the means of two groups with normally distributed data, which test should be used?

Accepted Answer

t-test

Answer

Chi-square test

Answer

Mann-Whitney U test

Answer

Kruskal-Wallis test

Question 15

A non-parametric measure of central tendency is the:

Accepted Answer

Median

Answer

Mean

Answer

Mode

Answer

Standard deviation

Question 16

In a study comparing two interventions, the chi-square test is used to test the null hypothesis that:

Accepted Answer

The two interventions have the same effect.

Answer

The first intervention is more effective than the second.

Answer

The second intervention is more effective than the first.

Answer

The two interventions have a significant difference in effectiveness.

Question 17

What is the null hypothesis for the Kruskal-Wallis test?

Accepted Answer

The median scores of the groups are equal.

Answer

The mean scores of the groups are equal.

Answer

The variance of the groups is equal.

Answer

The standard deviation of the groups is equal.

Question 18

Which of the following is a disadvantage of non-parametric tests?

Accepted Answer

They are less powerful than parametric tests.

Answer

They cannot handle large sample sizes.

Answer

They require more assumptions.

Answer

They cannot be used to compare rates.

Question 19

When would a researcher use a non-parametric test?

Accepted Answer

When the data is not normally distributed.

Answer

When the data is normally distributed.

Answer

When the sample size is large.

Answer

When the variables are quantitative.

Question 20

What is the purpose of the Mann-Whitney U test?

Accepted Answer

To compare two independent groups on a continuous variable.

Answer

To compare two independent groups on a nominal variable.

Answer

To compare three or more independent groups on a nominal variable.

Answer

To compare three or more independent groups on a continuous variable.

Question 21

In nursing research, what does a statistically significant chi-square test result suggest?

Accepted Answer

A statistically significant relationship between the categorical variables being analyzed.

Answer

The variables are not independent of each other.

Answer

The sample size is too small for the chi-square test to be valid.

Answer

The chi-square test is not appropriate for the type of data being analyzed.

Question 22

How does sample size impact the validity and power of parametric and non-parametric tests?

Accepted Answer

Larger sample sizes strengthen the validity and power of both parametric and non-parametric tests.

Answer

Larger sample sizes weaken the validity of both parametric and non-parametric tests.

Answer

Increased sample sizes enhance the power of parametric tests but reduce the power of non-parametric tests.

Answer

Increased sample sizes boost the validity of parametric tests while diminishing the power of non-parametric tests.

Question 23

Identify an assumption **NOT** required for the chi-square test:

Accepted Answer

The data must adhere to a normal distribution

Answer

Data should be categorical

Answer

Variables should be independent

Answer

Expected frequencies should be at least 5

Question 24

Which non-parametric test is suitable for comparing the medians of two independent groups?

Accepted Answer

Mann-Whitney U test

Answer

Wilcoxon signed-rank test

Answer

Kruskal-Wallis test

Answer

Chi-square test

Question 25

State the null hypothesis for the Kruskal-Wallis test:

Accepted Answer

Medians of all groups are equal

Answer

Variances of all groups are equal

Answer

Means of all groups are equal

Answer

Proportions of all groups are equal

Question 26

Identify a distinguishing feature of non-parametric tests:

Accepted Answer

Assumption of normality is not required

Answer

They are inherently less powerful than parametric tests

Answer

They can only be used with small sample sizes

Question 27

What is the primary purpose of non-parametric tests?

Accepted Answer

Hypothesis testing for populations when data violates parametric test assumptions

Answer

Estimating population parameters

Answer

Comparing group means

Question 28

Which of the following is a potential limitation of non-parametric tests?

Accepted Answer

Reduced power compared to parametric tests

Answer

Exclusive use with categorical data

Answer

Requirement for large sample sizes

Answer

Complex interpretation

Question 29

Explain the fundamental difference between parametric and non-parametric tests:

Accepted Answer

Parametric tests assume normality while non-parametric tests do not

Answer

Non-parametric tests are always more accurate

Answer

Parametric tests are always more powerful

Question 30

Which of the following is **NOT** a non-parametric test?

Accepted Answer

t-test

Answer

Mann-Whitney U test

Answer

Kruskal-Wallis test

Answer

Chi-square test

Question 31

State an advantage of using non-parametric tests:

Accepted Answer

Feasibility with data that violates parametric test assumptions

Answer

Easier interpretation compared to parametric tests

Answer

Guaranteed higher accuracy than parametric tests

Question 32

Identify an assumption of the Mann-Whitney U test:

Accepted Answer

Data should be ordinal or continuous

Answer

Normally distributed data

Answer

Equal variances between the two groups

Answer

Equal sample sizes for the two groups

Question 33

What is the main purpose of the Mann-Whitney U test?

Accepted Answer

To compare the medians of two independent groups.

Answer

To test the hypothesis that a median is equal to a specified value.

Answer

To compare the variances of two independent groups.

Answer

To determine if there is an association between two categorical variables.

Question 34

Which of the following is a potential limitation of the Kruskal-Wallis test?

Accepted Answer

It can be less powerful than the ANOVA test, especially when the sample sizes are small.

Answer

It can only be used with ordinal data.

Answer

It is not sensitive to outliers.

Answer

It assumes that the data is normally distributed.

Question 35

Which of the following non-parametric tests is used to test the hypothesis that two categorical variables are independent?

Accepted Answer

Chi-square test

Answer

Kruskal-Wallis test

Answer

t-test

Answer

Mann-Whitney U test

Question 36

What is the effect size measure for the Mann-Whitney U test?

Accepted Answer

Mann-Whitney U statistic

Answer

Chi-square statistic

Answer

Kruskal-Wallis statistic

Answer

t-statistic

Question 37

Which of the following is a disadvantage of using non-parametric tests?

Accepted Answer

They can be less powerful than parametric tests, especially when the sample sizes are large.

Answer

They require the assumption of normality in the population.

Answer

They cannot be used with large sample sizes.

Answer

They are more difficult to interpret than parametric tests.

Question 38

What is the null hypothesis for the Kruskal-Wallis test?

Accepted Answer

The medians of all groups are equal.

Answer

The means of all groups are equal.

Answer

The variances of all groups are equal.

Answer

The proportions of all groups are equal.

Question 39

Which of the following non-parametric tests can be used to test the hypothesis that a median is equal to a specified value?

Accepted Answer

Wilcoxon signed-rank test

Answer

Mann-Whitney U test

Answer

Kruskal-Wallis test

Answer

Chi-square test

Question 40

Among the assumptions of the chi-square test of independence, which one is paramount?

Accepted Answer

The observations are mutually independent.

Answer

All expected frequencies surpass 5.

Answer

The sample size is adequately large.

Answer

The data distribution approximates a normal distribution.

Question 41

When comparing two independent groups with data that deviate from a normal distribution, which non-parametric test is most appropriate?

Accepted Answer

Mann-Whitney U test

Answer

t-test

Answer

Kruskal-Wallis test

Answer

Chi-square test

Question 42

When interpreting the results of a chi-square test, a p-value below 0.05 suggests:

Accepted Answer

A statistically significant discrepancy between the observed and expected frequencies.

Answer

The data conform to a normal distribution.

Answer

A statistically insignificant discrepancy between the observed and expected frequencies.

Question 43

What is a key advantage of utilizing non-parametric tests?

Accepted Answer

They do not necessitate assumptions about the population's distribution.

Answer

They are computationally simpler than parametric tests.

Answer

They are inherently more powerful than parametric tests.

Question 44

When comparing three or more independent groups with data that deviate from a normal distribution, which non-parametric test is most appropriate?

Accepted Answer

Kruskal-Wallis test

Answer

Chi-square test

Answer

t-test

Answer

Mann-Whitney U test

Question 45

What is a fundamental distinction between parametric and non-parametric tests?

Accepted Answer

Parametric tests assume that data conform to a normal distribution.

Answer

Non-parametric tests can be applied to smaller sample sizes.

Answer

Parametric tests are inherently more powerful than non-parametric tests.

Question 46

When interpreting the results of a Kruskal-Wallis test, a p-value exceeding 0.05 indicates:

Accepted Answer

There is no statistically significant difference among the three or more groups.

Answer

There is a statistically significant difference among the three or more groups.

Answer

The data conform to a normal distribution.

Question 47

Which of the following is NOT a potential concern associated with using non-parametric tests?

Accepted Answer

They can be more powerful than parametric tests.

Answer

They can be more difficult to interpret than parametric tests.

Answer

They can be less efficient than parametric tests.

Answer

They can be more sensitive to outliers than parametric tests.

Question 48

A researcher wants to compare the median pain scores of patients receiving two different pain management techniques. The data is not normally distributed. Which non-parametric test is most appropriate for this comparison?

Accepted Answer

Mann-Whitney U test

Answer

Chi-square test

Answer

Paired t-test

Answer

Kruskal-Wallis test

Question 49

Which of the following is NOT a necessary assumption for the Mann-Whitney U test?

Accepted Answer

The data must be normally distributed.

Answer

The data should be at least ordinal.

Answer

The dependent variable should be continuous or ordinal.

Answer

The samples should be independent.

Question 50

A study investigates the association between smoking status (smoker vs. non-smoker) and the development of lung cancer (yes vs. no). Which non-parametric test is most suitable for analyzing this relationship between these two categorical variables?

Accepted Answer

Chi-square test

Answer

Wilcoxon signed-rank test

Answer

Kruskal-Wallis test

Answer

Mann-Whitney U test

Question 51

A significant p-value from a Kruskal-Wallis test indicates what about the medians of the groups being compared?

Accepted Answer

There is a significant difference in the medians of at least two groups.

Answer

There is no difference in the medians of the groups.

Answer

The data is normally distributed.

Question 52

A researcher wants to compare the effectiveness of three different handwashing techniques on reducing bacterial growth. They randomly assign 30 nurses to three groups (10 nurses per group) and measure the bacterial count after each technique. Which test is most appropriate to analyze this data, given that the bacterial count is likely not normally distributed?

Accepted Answer

Kruskal-Wallis test

Answer

Independent samples t-test

Answer

Mann-Whitney U test

Answer

Chi-square test

Question 53

Which of the following statements accurately describes a key characteristic of non-parametric tests compared to parametric tests?

Accepted Answer

They are less powerful than parametric tests when assumptions of normality are met.

Answer

They require the data to be normally distributed.

Answer

They are used when the sample size is large.

Question 54

What is the primary purpose of the chi-square test in statistical analysis?

Accepted Answer

Analyze the association between categorical variables.

Answer

Compare the means of two independent groups.

Answer

Compare the medians of two dependent groups.

Question 55

What is a significant advantage of using non-parametric tests in nursing research, especially when dealing with data that might not meet the assumptions of parametric tests?

Accepted Answer

They are robust to violations of normality assumptions.

Answer

They are always more powerful than parametric tests.

Answer

They can be used for any type of data.

Question 56

When reporting the results of a Mann-Whitney U test, what essential information should be included to provide a complete and informative summary of the findings?

Accepted Answer

The U statistic, p-value, and direction of the effect

Answer

The chi-square statistic and degrees of freedom

Answer

The mean and standard deviation of each group