Measures of Variability: Assess Data Spread in Nursing

Question 1

Which measure of variability remains unaffected by extreme values (outliers)?

Accepted Answer

Interquartile range

Answer

Range

Answer

Standard deviation

Answer

Variance

Question 2

Which measure of variability is defined as the square root of the average squared distance from the mean?

Accepted Answer

Standard deviation

Answer

Range

Answer

Interquartile range

Question 3

Which measure of variability quantifies the difference between the highest and lowest values in a dataset?

Accepted Answer

Range

Answer

Interquartile Range

Answer

Standard Deviation

Answer

Variance

Question 4

Which statement accurately describes standard deviation?

Accepted Answer

It quantifies the average distance of data points from the mean.

Answer

Its values can be negative.

Answer

It is always expressed in the same units as the original data.

Answer

It is a measure of central tendency.

Question 5

The variance of a dataset is numerically equal to the square of the:

Accepted Answer

Standard Deviation

Answer

Range

Answer

Interquartile Range

Answer

Mean

Question 6

Which measure of variability is most susceptible to extreme values?

Accepted Answer

Range

Answer

Interquartile Range

Answer

Standard Deviation

Answer

Variance

Question 7

In a normal distribution with a mean of 50 and a standard deviation of 10, what percentage of data values fall within one standard deviation of the mean?

Accepted Answer

68.2%

Answer

34.1%

Answer

95.4%

Answer

99.7%

Question 8

A nurse researcher collects data on the ages of patients in a clinic, and the data is skewed towards older ages. Which measure of variability is most suitable to report?

Accepted Answer

Interquartile Range

Answer

Range

Answer

Standard Deviation

Answer

Variance

Question 9

Which scenario would result in a dataset with a high standard deviation?

Accepted Answer

Students with a wide range of scores on a test.

Answer

Students scoring similarly on a test.

Answer

Students scoring below average on a test.

Answer

Students scoring the maximum possible score on a test.

Question 10

Which of the following is NOT considered a measure of variability?

Accepted Answer

Mean

Answer

Range

Answer

Interquartile range

Answer

Standard deviation

Question 11

The range of a dataset is calculated by subtracting the maximum value from what value?

Accepted Answer

Minimum value

Answer

Mean

Answer

Median

Answer

Standard deviation

Question 12

The standard deviation measures the:

Accepted Answer

Typical distance of data points from the mean

Answer

Maximum difference between data points

Answer

Spread of data points around the median

Answer

Proportion of data points that are outliers

Question 13

Which of the following is the square of the standard deviation?

Accepted Answer

Variance

Answer

Range

Answer

Interquartile range

Answer

Coefficient of variation

Question 14

A dataset with a smaller standard deviation is considered to have:

Accepted Answer

Less variability

Answer

More variability

Answer

The same variability

Answer

Cannot be determined

Question 15

Which of the following is NOT a measure of variability?

Accepted Answer

Mean

Answer

Standard deviation

Answer

Interquartile range

Answer

Coefficient of variation

Question 16

The measure of variability that calculates the difference between the lowest and highest data points is termed:

Accepted Answer

Range

Answer

Interquartile range

Answer

Standard deviation

Answer

Variance

Question 17

Which measure of variability represents the spread of the middle 50% of the data points?

Accepted Answer

Interquartile range

Answer

Range

Answer

Standard deviation

Answer

Variance

Question 18

The numerical square root of the variance is known as:

Accepted Answer

Standard deviation

Answer

Mean

Answer

Median

Answer

Range

Question 19

A larger variance in a dataset indicates:

Accepted Answer

Greater spread of data points

Answer

Higher central tendency

Answer

Narrower range

Answer

Lower interquartile range

Question 20

Which dataset has the largest standard deviation?

Accepted Answer

{0, 10, 20, 30, 40}

Answer

{1, 2, 3, 4, 5}

Answer

{2, 4, 6, 8, 10}

Answer

{5, 5, 5, 5, 5}

Question 21

Measures of variability primarily serve the purpose of:

Accepted Answer

All of the above options

Answer

describing data distributions

Answer

drawing inferences about populations

Answer

comparing different datasets

Question 22

When analyzing a dataset with extreme outliers, the most appropriate measure of variability is:

Accepted Answer

Interquartile range

Answer

Mean

Answer

Median

Answer

Standard deviation

Question 23

Which factor does NOT influence the variance of a dataset?

Accepted Answer

Central tendency

Answer

Sample size

Answer

Spread of data

Answer

Presence of outliers

Question 24

In general, how does the interquartile range (IQR) differ between a normally distributed dataset and a dataset with a skewed distribution?

Accepted Answer

The IQR is larger in a skewed distribution than in a normally distributed dataset.

Answer

The IQR is smaller in a skewed distribution than in a normally distributed dataset.

Answer

The IQR is the same in both normally distributed and skewed datasets.

Answer

IQR cannot be calculated for datasets with skewed distributions.

Question 25

Which measure of variability represents the difference between the highest and lowest values in a dataset?

Accepted Answer

Range

Answer

Standard deviation

Answer

Variance

Answer

Interquartile range

Question 26

Which measure of variability is most affected by extreme values?

Accepted Answer

Range

Answer

Interquartile range

Answer

Standard deviation

Answer

Variance

Question 27

A dataset has a mean of 10 and a standard deviation of 5. What is the z-score for a value of 15?

Accepted Answer

1

Answer

0.5

Answer

1.5

Question 28

Which formula represents variance?

Accepted Answer

σ² = Σ(x - μ)² / N

Answer

σ = Σ(x - μ) / N

Answer

σ² = (Σx)² / N

Answer

σ = (Σ(x - μ)²) / N

Question 29

Which measure of variability quantifies the spread of data relative to its average value?

Accepted Answer

Standard deviation

Answer

Range

Answer

Variance

Answer

Interquartile range

Question 30

A patient's blood glucose levels have a variance of 16. What is the standard deviation of these results?

Accepted Answer

4

Answer

2

Answer

8

Question 31

Which measure of variability is most heavily influenced by extreme values in a dataset?

Accepted Answer

Range

Answer

Variance

Answer

Standard deviation

Answer

Interquartile range (IQR)

Question 32

The interquartile range (IQR) represents the:

Accepted Answer

Middle 50% of data values

Answer

Median and mean values

Answer

Upper and lower 25% of data values

Answer

Maximum and minimum values

Question 33

Which measure of variability quantifies the average distance of data points from the mean?

Accepted Answer

Standard deviation

Answer

Interquartile range (IQR)

Answer

Range

Answer

Variance

Question 34

The relationship between variance and standard deviation is expressed by the formula:

Accepted Answer

Variance = (Standard deviation)^2

Answer

Standard deviation = (Variance)^2

Answer

Standard deviation = (Variance)^3

Answer

Variance = (Standard deviation)^3

Question 35

Which of the following datasets exhibits the greatest variability?

Accepted Answer

Dataset with a large standard deviation and range

Answer

Dataset with a small standard deviation and small range

Answer

Dataset with a small standard deviation and large range

Answer

Dataset with a large standard deviation and small range

Question 36

In nursing practice, measures of variability are valuable because they:

Accepted Answer

Facilitate analysis and interpretation of data variability to support evidence-based decision-making

Answer

Can be used as the sole measure for patient outcomes

Answer

Provide definitive diagnoses for patient conditions

Question 37

Measures of variability are commonly used in conjunction with:

Accepted Answer

Measures of central tendency

Answer

Measures of probability

Answer

Measures of correlation

Answer

Measures of significance

Question 38

Which of the following is a measure of variability?

Accepted Answer

Standard deviation

Answer

Mode

Answer

Mean

Answer

Median

Question 39

The interquartile range (IQR) of a data set is 12. What does this indicate about the data distribution?

Accepted Answer

The middle 50% of the data values differ by 12 units.

Answer

The data is normally distributed.

Answer

The data is symmetrically distributed.

Question 40

Which measure of variability is most sensitive to outliers?

Accepted Answer

Range

Answer

Interquartile range

Answer

Standard deviation

Answer

Variance

Question 41

The standard deviation of a data set is 5. What percentage of the data values fall within one standard deviation of the mean?

Accepted Answer

68%

Answer

80%

Answer

95%

Answer

50%

Question 42

Which of the following is a limitation of using variability measures?

Accepted Answer

They do not provide information about the shape of the data distribution.

Answer

They are only applicable to normally distributed data sets.

Answer

They are difficult to calculate.

Question 43

In a data set, the range is 10 and the standard deviation is 2. Which of the following is most likely?

Accepted Answer

There are outliers in the data set.

Answer

The data is skewed to the right.

Answer

The data is normally distributed.

Question 44

Which variability measure is most appropriate to use when comparing the variability of two data sets with different sample sizes?

Accepted Answer

Coefficient of variation

Answer

Variance

Answer

Range

Answer

Standard deviation

Question 45

Two groups of patients, Group A and Group B, have the same average weight. However, Group A has a larger standard deviation compared to Group B. What can we infer about the distribution of weights within each group?

Accepted Answer

The weights of patients in Group A are more dispersed.

Answer

The weights of patients in Group B are less dispersed.

Answer

There is no difference in the dispersion of weights between Group A and B.

Question 46

A study reports the interquartile range (IQR) of patient recovery times after a specific surgical procedure. What information does the IQR provide?

Accepted Answer

The spread of recovery times between the 25th and 75th percentiles.

Answer

The maximum recovery time.

Answer

The average recovery time.

Question 47

Which measure of variability is most susceptible to the influence of extreme values (outliers)?

Accepted Answer

Range

Answer

Variance

Answer

Standard deviation

Answer

Interquartile range

Question 48

A nurse is comparing the effectiveness of two pain relievers for post-operative patients. She observes that both medications have similar average pain reduction, but Medication A exhibits a lower standard deviation than Medication B. What can the nurse conclude?

Accepted Answer

Medication A provides more consistent pain relief.

Answer

Medication B is more potent than Medication A.

Answer

There is no significant difference in pain relief consistency between the two medications.

Question 49

When comparing patient satisfaction data from Hospital Units A and B, the following information is available: Unit A: mean satisfaction score of 8.5, standard deviation of 0.5; Unit B: mean satisfaction score of 8.5, standard deviation of 1.2. Which unit exhibits greater variability in patient satisfaction?

Accepted Answer

Unit B

Answer

Both units have the same variability.

Answer

The provided information is insufficient to determine.

Answer

Unit A

Question 50

Which of the following is not considered a measure of variability?

Accepted Answer

Mean

Answer

Range

Answer

Variance

Answer

Standard deviation