Solution Manual for
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Statistics for Nursingn n
n Research A n
n Workbookfor n
n Evidence-Based
n Practice 3rd Edition
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n Susan Grove Daisha
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, Answer Guidelines for Questions to Be Graded n n n n n n
EXERCISE
Identifying Levels n
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n ofMeasurement: Nominal,
Ordinal, Interval, and
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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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nrationale for your answer. n n n
Answer: The current therapy variable was measured at the nominal level. These drug
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categories were probably developed to be exhaustive for this study and included the categories
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of drugs the subjects were receiving. However, the categories are not exclusive, since patients
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are usually on more than one category of these drugs to manage their health problems. The
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current therapies are not measured at the ordinal level because they cannot be rank ordered, since
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no drug category can be considered more or less beneficial than another drug category (see
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Figure 1-1; Grove & Gray, 2019).
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2. What is the mode for the current therapy variable in this study? Provide a rationale
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foryour answer.
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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
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for thissample.
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3. What statistics were conducted to describe the BMI of the cardiac patients in this
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sample?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
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resulted in ratio-level data with continuous values and an absolute zero (Stone & Frazier,
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2017). Ratio- level data should be analyzed with parametric statistics such as the mean and SD
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(Grove & Gray,2017; Knapp, 2017).
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4. Researchers used the following item to measure registered nurses’ (RNs) income in a
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study:What category identifies your current income as an RN?
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a. Less than $50,000
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b. $50,000 to 59,999
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c. $60,000 to 69,999
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d. $70,000 to 80,000
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e. $80,000 or greater
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What level of measurement is this income variable? Does the income variable follow
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the 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
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catego- ries are exhaustive, ranging from less than $50,000 to greater than $80,000. The two
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open-ended
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n Answer n Guidelines n for n Questions n to n Be n Graded
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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neither (d) or (e) or both categories, resulting in erroneous data. Category (e) could be
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nchanged to greater than $80,000, making the categories exclusive. The categories can be rank
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nordered from the lowest salary to the highest salary, which is consistent with ordinal data
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n(Grove & 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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6. Were nonparametric or parametric analysis techniques used to analyze the CDS scores
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forthe 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
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nscores for study participants (see Table 1). CDS scores are interval-level data as indicated in
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Questions 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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nimportance of this result. n n n
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
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the subjects were depressed in NYHA class I. Thus, as the NYHA class increased, the number of
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sub- jects with depression increased. This is an expected finding because as the NYHA class
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increases, cardiac patients have more severe physical symptoms, which usually result in emotional
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distress, such as depression. Nurses need to actively assess cardiac patients for depression,
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nespecially thosein 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 included
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15 patients who were receiving an antidepressant (see Table 1). The number of cardiac
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patients not treated for depression was 91 (106 – 15 = 91). The group percent is
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calculated by the following formula: (group frequency ÷ total sample size) × 100%.
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nFor this study, (91 patients ÷ 106 sample size) × 100% = 0.858 × 100% = 85.8% =
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86%. The final answer is rounded to the nearest whole percent as directed in the
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question. You could have also subtracted the 14% of patients treated with antidepressants
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from 100% and obtained the 86% who were not treated with an antidepressant.
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9. What was the purpose of the 6-minute walk test (6MWT)? Would the 6MWT 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
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submaximal, steady-state functional capacity‖ of cardiac patients. This test would be a quick,
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easy way to determine a cardiac patient’s functional status in a clinical setting. This
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functional status score could be used to determine the treatment plan to promote or
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maintain functional statusof cardiac patients.
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, Answer n Guidelines n for n Questions n to n Be n Graded AG 1-3
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10. How was exercise confidence measured in this study? What was the level of
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measurementfor the exercise confidence variable in this study? Provide a rationale for
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your answer. Answer: Exercise confidence of the patients with heart failure (HF) in this
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study was measuredwith the Exercise Confidence Scale that included four subscales focused
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on walking, climbing,lifting objects of graded weight, and running (see the study narrative).
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This was a rating scalewith values ranging from 0 to 100. The patients’ scores for the Total
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Exercise Confidence scaleand the subscales were considered interval-level data and
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analyzed with parametric statistics,such as means and SDs (see the study narrative; Waltz et
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al., 2017).
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