SolutionManualfor
b b
Statistics for Nursing
b b
Research A Workbook
b b b
for Evidence-Based
b b
Practice 3rd Edition
b b b
SusanGroveDaisha
b b b
, Answer Guidelines for Questions to Be Graded b b b b b b
EXERCISE
Identifying Levels of b
1
b b
Measurement: Nominal, b b
Ordinal, Interval, and Ratio
b b b b
The questions are in bold followed by answers.
b b b b b b b
1. In Table 1, identify the level of measurement for the current therapy variable. Provide a
b b b b b b b b b b b b b b
rationale for your answer.
b b b b
Answer: The current therapy variable was measured at the nominal level. These drug categories
b b b b b b b b b b b b b
were probably developed to be exhaustive for this study and included the categories of drugs the
b b b b b b b b b b b b b b b b
subjects were receiving. However, the categories are not exclusive, since patients are usually on
b b b b b b b b b b b b b b
more than one category of these drugs to manage their health problems. The current therapies are
b b b b b b b b b b b b b b b b
not measured at the ordinal level because they cannot be rank ordered, since no drug category can be
b b b b b b b b b b b b b b b b b b
considered more or less beneficial than another drug category (see Figure 1-1; Grove & Gray,
b b b b b b b b b b b b b b b
2019).
b
2. What is the mode for the current therapy variable in this study? Provide a rationale for
b b b b b b b b b b b b b b b
your answer.
b b
Answer: The mode for current therapy was β blocker. A total of 100 (94%) of the cardiac patients
b b b b b b b b b b b b b b b b b
were receiving this category of drug, which was the most common prescribed drug for
b b b b b b b b b b b b b
thissample.
b b
3. What statistics were conducted to describe the BMI of the cardiac patients in this sample?
b b b b b b b b b b b b b b
Discuss whether these analysis techniques were appropriate or inappropriate.
b b b b b b b b b
Answer: BMI was described with a mean and standard deviation (SD). BMI measurement resulted in
b b b b b b b b b b b b b b
ratio-level data with continuous values and an absolute zero (Stone & Frazier, 2017). Ratio- level
b b b b b b b b b b b b b b b
data should be analyzed with parametric statistics such as the mean and SD (Grove & Gray, 2017;
b b b b b b b b b b b b b b b b b
Knapp, 2017).
b b
4. Researchers used the following item to measure registered nurses’ (RNs) income in a study:
b b b b b b b b b b b b b
What category identifies your current income as an RN?
b b b b b b b b b
a. Less than $50,000
b b b
b. $50,000 to 59,999
b b b
c. $60,000 to 69,999
b b b
d. $70,000 to 80,000
b b b
e. $80,000 or greater
b b b
What level of measurement is this income variable? Does the income variable follow the
b b b b b b b b b b b b b
rules outlined in Figure 1-1? Provide a rationale for your answer.
b b b b b b b b b b b
Answer: In this example, the income variable is measured at the ordinal level. The income catego- ries
b b b b b b b b b b b b b b b b
are exhaustive, ranging from less than $50,000 to greater than $80,000. The two open-ended
b b b b b b b b b b b b b b
AG 1-1 b
,AG 1-2 b Answer Guidelines for Questions to Be Graded b b b b b b
categories ensure that all salary levels are covered. The categories are not exclusive, since catego-ries
b b b b b b b b b b b b b b b
(d) and (e) include an $80,000 salary, so study participants making $80,000 might mark either (d)
b b b b b b b b b b b b b b b b
or (e) or both categories, resulting in erroneous data. Category (e) could be changed to greater
b b b b b b b b b b b b b b b b
than $80,000, making the categories exclusive. The categories can be rank ordered from the lowest
b b b b b b b b b b b b b b b
salary to the highest salary, which is consistent with ordinal data (Grove & Gray, 2019; Waltz et al.,
b b b b b b b b b b b b b b b b b b
2017).
b
5. What level of measurement is the CDS score? Provide a rationale for your answer.
b b b b b b b b b b b b b
Answer: The CDS score is at the interval level of measurement. The CDS is a 26-item Likert scale
b b b b b b b b b b b b b b b b b
developed to measure depression in cardiac patients. Study participants rated their symp- toms on a
b b b b b b b b b b b b b b b
scale of 1 to 7, with higher numbers indicating increased severity in the depression symptoms. The
b b b b b b b b b b b b b b b b
total scores for each subject obtained from this multi-item scale are considered to be at the interval
b b b b b b b b b b b b b b b b b
level of measurement (Gray et al., 2017; Waltz et al., 2017).
b b b b b b b b b b b
6. Were nonparametric or parametric analysis techniques used to analyze the CDS scores forthe
b b b b b b b b b b b b b
cardiac patients in this study? Provide a rationale for your answer.
b b b b b b b b b b b
Answer: Parametric statistics, such as mean and SD, were conducted to describe CDS scores
b b b b b b b b b b b b b
for study participants (see Table 1). CDS scores are interval-level data as indicated in Questions 5, so
b b b b b b b b b b b b b b b b b
parametric statistics are appropriate for this level of data (Gray et al., 2017; Kim & Mallory, 2017).
b b b b b b b b b b b b b b b b b
7. Is the prevalence of depression linked to the NYHA class? Discuss the clinical importance of
b b b b b b b b b b b b b b
this result.
b b
Answer: The study narrative indicated that the prevalence of depression increased with the greater
b b b b b b b b b b b b b
NYHA class. In NYHA class III, 64% of the subjects were depressed, whereas 11% of thesubjects were
b b b b b b b b b b b b b b b b b b
depressed in NYHA class I. Thus, as the NYHA class increased, the number of sub- jects with
b b b b b b b b b b b b b b b b b
depression increased. This is an expected finding because as the NYHA class increases, cardiac
b b b b b b b b b b b b b b
patients have more severe physical symptoms, which usually result in emotional distress, such as
b b b b b b b b b b b b b b
depression. Nurses need to actively assess cardiac patients for depression, especially thosein higher
b b b b b b b b b b b b b b
NYHA classes, so they might be diagnosed and treated as needed.
b b b b b b b b b b b
8. What frequency and percent of cardiac patients in this study were not being treated with an
b b b b b b b b b b b b b b b
antidepressant? Show your calculations and round your answer to the nearest whole percent
b b b b b b b b b b b b b
(%).
b
Answer: A total of 106 cardiac patients participated in this study. The sample included 15
b b b b b b b b b b b b b b b b b b b b b b b b b
patients who were receiving an antidepressant (see Table 1). The number of cardiac patients not
b b b b b b b b b b b b b b b b b b
treated for depression was 91 (106 – 15 = 91). The group percent is calculated by the
b b b b b b b b b b b b b b b b b
bfollowing formula: (group frequency ÷ total sample size) × 100%. For this study, (91 b b b b b b b b b b b b b
patients ÷ 106 sample size) × 100% = 0.858 × 100% = 85.8% = 86%. The final answer is
b b b b b b b b b b b b b b b b b b b b
rounded to the nearest whole percent as directed in the question. You could have also
b b b b b b b b b b b b b b b
subtracted the 14% of patients treated with antidepressants from 100% and obtained the 86% who
b b b b b b b b b b b b b b b
were not treated with an antidepressant.
b b b b b b
9. What was the purpose of the 6-minute walk test (6MWT)? Would the 6MWT be useful in
b b b b b b b b b b b b b b b
clinical practice?
b b
Answer: Ha et al. (2018) stated, “The 6-min walk test (6MWT) is a measure of the submaximal,
b b b b b b b b b b b b b b b b
steady-state functional capacity” of cardiac patients. This test would be a quick, easy way to
b b b b b b b b b b b b b b b
determine a cardiac patient’s functional status in a clinical setting. This functional status score
b b b b b b b b b b b b b b b b b b
could be used to determine the treatment plan to promote or maintain functional status of
b b b b b b b b b b b b b b b
cardiac patients.
b b
, Answer Guidelines for Questions to Be Graded
b b b b b b AG 1-3 b
10. How was exercise confidence measured in this study? What was the level of measurementfor
b b b b b b b b b b b b b b
the exercise confidence variable in this study? Provide a rationale for your answer. Answer:
b b b b b b b b b b b b b b
Exercise confidence of the patients with heart failure (HF) in this study was measuredwith the
b b b b b b b b b b b b b b b b
Exercise Confidence Scale that included four subscales focused on walking, climbing,lifting
b b b b b b b b b b b b
objects of graded weight, and running (see the study narrative). This was a rating scalewith
b b b b b b b b b b b b b b b b
values ranging from 0 to 100. The patients’ scores for the Total Exercise Confidence scaleand the
b b b b b b b b b b b b b b b b b
subscales were considered interval-level data and analyzed with parametric statistics,such as
b b b b b b b b b b b b
means and SDs (see the study narrative; Waltz et al., 2017).
b b b b b b b b b b b
b b
Statistics for Nursing
b b
Research A Workbook
b b b
for Evidence-Based
b b
Practice 3rd Edition
b b b
SusanGroveDaisha
b b b
, Answer Guidelines for Questions to Be Graded b b b b b b
EXERCISE
Identifying Levels of b
1
b b
Measurement: Nominal, b b
Ordinal, Interval, and Ratio
b b b b
The questions are in bold followed by answers.
b b b b b b b
1. In Table 1, identify the level of measurement for the current therapy variable. Provide a
b b b b b b b b b b b b b b
rationale for your answer.
b b b b
Answer: The current therapy variable was measured at the nominal level. These drug categories
b b b b b b b b b b b b b
were probably developed to be exhaustive for this study and included the categories of drugs the
b b b b b b b b b b b b b b b b
subjects were receiving. However, the categories are not exclusive, since patients are usually on
b b b b b b b b b b b b b b
more than one category of these drugs to manage their health problems. The current therapies are
b b b b b b b b b b b b b b b b
not measured at the ordinal level because they cannot be rank ordered, since no drug category can be
b b b b b b b b b b b b b b b b b b
considered more or less beneficial than another drug category (see Figure 1-1; Grove & Gray,
b b b b b b b b b b b b b b b
2019).
b
2. What is the mode for the current therapy variable in this study? Provide a rationale for
b b b b b b b b b b b b b b b
your answer.
b b
Answer: The mode for current therapy was β blocker. A total of 100 (94%) of the cardiac patients
b b b b b b b b b b b b b b b b b
were receiving this category of drug, which was the most common prescribed drug for
b b b b b b b b b b b b b
thissample.
b b
3. What statistics were conducted to describe the BMI of the cardiac patients in this sample?
b b b b b b b b b b b b b b
Discuss whether these analysis techniques were appropriate or inappropriate.
b b b b b b b b b
Answer: BMI was described with a mean and standard deviation (SD). BMI measurement resulted in
b b b b b b b b b b b b b b
ratio-level data with continuous values and an absolute zero (Stone & Frazier, 2017). Ratio- level
b b b b b b b b b b b b b b b
data should be analyzed with parametric statistics such as the mean and SD (Grove & Gray, 2017;
b b b b b b b b b b b b b b b b b
Knapp, 2017).
b b
4. Researchers used the following item to measure registered nurses’ (RNs) income in a study:
b b b b b b b b b b b b b
What category identifies your current income as an RN?
b b b b b b b b b
a. Less than $50,000
b b b
b. $50,000 to 59,999
b b b
c. $60,000 to 69,999
b b b
d. $70,000 to 80,000
b b b
e. $80,000 or greater
b b b
What level of measurement is this income variable? Does the income variable follow the
b b b b b b b b b b b b b
rules outlined in Figure 1-1? Provide a rationale for your answer.
b b b b b b b b b b b
Answer: In this example, the income variable is measured at the ordinal level. The income catego- ries
b b b b b b b b b b b b b b b b
are exhaustive, ranging from less than $50,000 to greater than $80,000. The two open-ended
b b b b b b b b b b b b b b
AG 1-1 b
,AG 1-2 b Answer Guidelines for Questions to Be Graded b b b b b b
categories ensure that all salary levels are covered. The categories are not exclusive, since catego-ries
b b b b b b b b b b b b b b b
(d) and (e) include an $80,000 salary, so study participants making $80,000 might mark either (d)
b b b b b b b b b b b b b b b b
or (e) or both categories, resulting in erroneous data. Category (e) could be changed to greater
b b b b b b b b b b b b b b b b
than $80,000, making the categories exclusive. The categories can be rank ordered from the lowest
b b b b b b b b b b b b b b b
salary to the highest salary, which is consistent with ordinal data (Grove & Gray, 2019; Waltz et al.,
b b b b b b b b b b b b b b b b b b
2017).
b
5. What level of measurement is the CDS score? Provide a rationale for your answer.
b b b b b b b b b b b b b
Answer: The CDS score is at the interval level of measurement. The CDS is a 26-item Likert scale
b b b b b b b b b b b b b b b b b
developed to measure depression in cardiac patients. Study participants rated their symp- toms on a
b b b b b b b b b b b b b b b
scale of 1 to 7, with higher numbers indicating increased severity in the depression symptoms. The
b b b b b b b b b b b b b b b b
total scores for each subject obtained from this multi-item scale are considered to be at the interval
b b b b b b b b b b b b b b b b b
level of measurement (Gray et al., 2017; Waltz et al., 2017).
b b b b b b b b b b b
6. Were nonparametric or parametric analysis techniques used to analyze the CDS scores forthe
b b b b b b b b b b b b b
cardiac patients in this study? Provide a rationale for your answer.
b b b b b b b b b b b
Answer: Parametric statistics, such as mean and SD, were conducted to describe CDS scores
b b b b b b b b b b b b b
for study participants (see Table 1). CDS scores are interval-level data as indicated in Questions 5, so
b b b b b b b b b b b b b b b b b
parametric statistics are appropriate for this level of data (Gray et al., 2017; Kim & Mallory, 2017).
b b b b b b b b b b b b b b b b b
7. Is the prevalence of depression linked to the NYHA class? Discuss the clinical importance of
b b b b b b b b b b b b b b
this result.
b b
Answer: The study narrative indicated that the prevalence of depression increased with the greater
b b b b b b b b b b b b b
NYHA class. In NYHA class III, 64% of the subjects were depressed, whereas 11% of thesubjects were
b b b b b b b b b b b b b b b b b b
depressed in NYHA class I. Thus, as the NYHA class increased, the number of sub- jects with
b b b b b b b b b b b b b b b b b
depression increased. This is an expected finding because as the NYHA class increases, cardiac
b b b b b b b b b b b b b b
patients have more severe physical symptoms, which usually result in emotional distress, such as
b b b b b b b b b b b b b b
depression. Nurses need to actively assess cardiac patients for depression, especially thosein higher
b b b b b b b b b b b b b b
NYHA classes, so they might be diagnosed and treated as needed.
b b b b b b b b b b b
8. What frequency and percent of cardiac patients in this study were not being treated with an
b b b b b b b b b b b b b b b
antidepressant? Show your calculations and round your answer to the nearest whole percent
b b b b b b b b b b b b b
(%).
b
Answer: A total of 106 cardiac patients participated in this study. The sample included 15
b b b b b b b b b b b b b b b b b b b b b b b b b
patients who were receiving an antidepressant (see Table 1). The number of cardiac patients not
b b b b b b b b b b b b b b b b b b
treated for depression was 91 (106 – 15 = 91). The group percent is calculated by the
b b b b b b b b b b b b b b b b b
bfollowing formula: (group frequency ÷ total sample size) × 100%. For this study, (91 b b b b b b b b b b b b b
patients ÷ 106 sample size) × 100% = 0.858 × 100% = 85.8% = 86%. The final answer is
b b b b b b b b b b b b b b b b b b b b
rounded to the nearest whole percent as directed in the question. You could have also
b b b b b b b b b b b b b b b
subtracted the 14% of patients treated with antidepressants from 100% and obtained the 86% who
b b b b b b b b b b b b b b b
were not treated with an antidepressant.
b b b b b b
9. What was the purpose of the 6-minute walk test (6MWT)? Would the 6MWT be useful in
b b b b b b b b b b b b b b b
clinical practice?
b b
Answer: Ha et al. (2018) stated, “The 6-min walk test (6MWT) is a measure of the submaximal,
b b b b b b b b b b b b b b b b
steady-state functional capacity” of cardiac patients. This test would be a quick, easy way to
b b b b b b b b b b b b b b b
determine a cardiac patient’s functional status in a clinical setting. This functional status score
b b b b b b b b b b b b b b b b b b
could be used to determine the treatment plan to promote or maintain functional status of
b b b b b b b b b b b b b b b
cardiac patients.
b b
, Answer Guidelines for Questions to Be Graded
b b b b b b AG 1-3 b
10. How was exercise confidence measured in this study? What was the level of measurementfor
b b b b b b b b b b b b b b
the exercise confidence variable in this study? Provide a rationale for your answer. Answer:
b b b b b b b b b b b b b b
Exercise confidence of the patients with heart failure (HF) in this study was measuredwith the
b b b b b b b b b b b b b b b b
Exercise Confidence Scale that included four subscales focused on walking, climbing,lifting
b b b b b b b b b b b b
objects of graded weight, and running (see the study narrative). This was a rating scalewith
b b b b b b b b b b b b b b b b
values ranging from 0 to 100. The patients’ scores for the Total Exercise Confidence scaleand the
b b b b b b b b b b b b b b b b b
subscales were considered interval-level data and analyzed with parametric statistics,such as
b b b b b b b b b b b b
means and SDs (see the study narrative; Waltz et al., 2017).
b b b b b b b b b b b
