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