Solution Manual for
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Statistics for Nursing
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h Research A Workbook for
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h Evidence-Based Practice h
h 3rd Edition Susan Grove
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h Daisha
, Answer Guidelines for Questions to Be Graded h h h h h h
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Measurement: Nominal,
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1
The questions are in bold followed by answers.
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1. In Table 1, identify the level of measurement for the current therapy variable. Provide a
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h rationale for your answer. h h h
Answer: The current therapy variable was measured at the nominal level. These drug categories
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hwere probably developed to be exhaustive for this study and included the categories of drugs the
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hsubjects were receiving. However, the categories are not exclusive, since patients are usually
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hon more than one category of these drugs to manage their health problems. The current
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htherapies are not measured at the ordinal level because they cannot be rank ordered, since no drug
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hcategory can be considered more or less beneficial than another drug category (see Figure 1-1;
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hGrove & Gray, 2019). h h h
2. What is the mode for the current therapy variable in this study? Provide a rationale for
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h your answer. h
Answer: The mode for current therapy was β blocker. A total of 100 (94%) of the cardiac patients
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were receiving this category of drug, which was the most common prescribed drug for this
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hsample.
3. What statistics were conducted to describe the BMI of the cardiac patients in this
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hsample? Discuss whether these analysis techniques were appropriate or inappropriate.
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Answer: BMI was described with a mean and standard deviation (SD). BMI measurement resulted
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hin ratio-level data with continuous values and an absolute zero (Stone & Frazier, 2017). Ratio-
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hlevel data should be analyzed with parametric statistics such as the mean and SD (Grove & Gray,
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h2017; Knapp, 2017). h h
4. Researchers used the following item to measure registered nurses’ (RNs) income in a study:
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h What category identifies your current income as an RN?
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a. Less than $50,000 h h
b. $50,000 to 59,999 h h
c. $60,000 to 69,999 h h
d. $70,000 to 80,000 h h
e. $80,000 or greater h h
What level of measurement is this income variable? Does the income variable follow the
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rules outlined in Figure 1-1? Provide a rationale for your answer.
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Answer: In this example, the income variable is measured at the ordinal level. The income catego-
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ries are exhaustive, ranging from less than $50,000 to greater than $80,000. The two open-
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ended
AG 1-1 h
,AG 1-2 h Answer hGuidelines hfor hQuestions hto hBe hGraded
categories ensure that all salary levels are covered. The categories are not exclusive, since catego-
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ries (d) and (e) include an $80,000 salary, so study participants making $80,000 might mark
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either (d) or (e) or both categories, resulting in erroneous data. Category (e) could be changed
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hto greater than $80,000, making the categories exclusive. The categories can be rank ordered
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from the lowest salary to the highest salary, which is consistent with ordinal data (Grove &
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Gray, 2019; Waltz et al., 2017).
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5. What level of measurement is the CDS score? Provide a rationale for your answer.
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Answer: The CDS score is at the interval level of measurement. The CDS is a 26-item Likert
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scale developed to measure depression in cardiac patients. Study participants rated their symp-
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toms on a scale of 1 to 7, with higher numbers indicating increased severity in the depression
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symptoms. The total scores for each subject obtained from this multi-item scale are
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considered to be at the interval level of measurement (Gray et al., 2017; Waltz et al., 2017).
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5. Were nonparametric or parametric analysis techniques used to analyze the CDS scores for
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the cardiac patients in this study? Provide a rationale for your answer.
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Answer: Parametric statistics, such as mean and SD, were conducted to describe CDS scores
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for study participants (see Table 1). CDS scores are interval-level data as indicated in Questions
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5, so parametric statistics are appropriate for this level of data (Gray et al., 2017; Kim &
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Mallory, 2017).
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7. Is the prevalence of depression linked to the NYHA class? Discuss the clinical
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importance of this result.
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Answer: The study narrative indicated that the prevalence of depression increased with the
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greater NYHA class. In NYHA class III, 64% of the subjects were depressed, whereas 11% of the
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subjects were depressed in NYHA class I. Thus, as the NYHA class increased, the number of sub-
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jects with depression increased. This is an expected finding because as the NYHA class increases,
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cardiac patients have more severe physical symptoms, which usually result in emotional distress,
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such as depression. Nurses need to actively assess cardiac patients for depression, especially those
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in higher NYHA classes, so they might be diagnosed and treated as needed.
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8. What frequency and percent of cardiac patients in this study were not being treated
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with an antidepressant? Show your calculations and round your answer to the nearest
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whole percent (%).
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Answer: A total of 106 cardiac patients participated in this study. The sample
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included 15 patients who were receiving an antidepressant (see Table 1). The
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number of cardiac patients not treated for depression was 91 (106 – 15 = 91). The
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group percent is calculated by the following formula: (group frequency ÷ total sample
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size) × 100%. For this study, (91 patients ÷ 106 sample size) × 100% = 0.858 ×
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100% = 85.8% = 86%. The final answer is rounded to the nearest whole percent as
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directed in the question. You could have also subtracted the 14% of patients treated with
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antidepressants from 100% and obtained the 86% who were not treated with an
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antidepressant.
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t. What was the purpose of the 5-minute walk test (5MWT)? Would the 5MWT be useful
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in clinical practice?
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Answer: Ha et al. (2018) stated, “The 6-min walk test (6MWT) is a measure of the submaximal,
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steady-state functional capacity” of cardiac patients. This test would be a quick, easy way to
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determine a cardiac patient’s functional status in a clinical setting. This functional
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status score could be used to determine the treatment plan to promote or maintain
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functional status of cardiac patients.
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, Answer hGuidelines hfor hQuestions hto hBe hGraded AG 1-3 h
10. How was exercise confidence measured in this study? What was the level of measurement
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for the exercise confidence variable in this study? Provide a rationale for your answer.
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Answer: Exercise confidence of the patients with heart failure (HF) in this study was measured
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with the Exercise Confidence Scale that included four subscales focused on walking, climbing,
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lifting objects of graded weight, and running (see the study narrative). This was a rating scale
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with values ranging from 0 to 100. The patients’ scores for the Total Exercise Confidence scale
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and the subscales were considered interval-level data and analyzed with parametric statistics,
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such as means and SDs (see the study narrative; Waltz et al., 2017).
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