Statistics for Nursing Res
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earch A Workbook for Evi
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dence-
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Based Practice 3rd Editio
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n Susan Grove Daisha
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,AnswerVGuidelinesVforVQuestionsVtoVBeVGraded
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
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m variable. Pr ovide a rationale for your answer. m m m m m m m
Answer: The current therapy variable was measured at the nominal level. These drug c
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m ategories were probably developed to be exhaustive for this study and included the cate
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mgories of drugs the subjects were receiving. However, the categories are not exclusive,
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msince patients are usually on more than one category of these drugs to manage their h
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mealth problems. The current therapies are not measured at the ordinal level because they
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mcannot be rank ordered, since no drug category can be considered more or less
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m benefi cial than another drug category (see 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
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m ratio nale for your answer. m m m m
Answer: The mode for current therapy was β blocker. A total of 100 (94%) of the cardiac
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m patie nts m
were receiving this category of drug, which was the most common prescribed drug
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m for t his sample. m m m
3. What statistics were conducted to describe the BMI of the cardiac patients in
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m this sample? Discuss whether these analysis techniques were appropriate or
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m inappropri ate. m
Answer: BMI was described with a mean and standard deviation (SD). BMI measurement resulted
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in ratio-
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level data with continuous values and an absolute zero (Stone & Frazier, 2017). Ratio-
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mlevel data should be analyzed with parametric statistics such as the mean and SD
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m (Gro ve & Gray, 2017; Knapp, 2017).
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4. Researchers used the following item to measure registered nurses’ (RNs) income in a m m m m m m m m m m m m
mstudy: 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
m
c. $60,000 to 69,999
m
d. $70,000 to 80,000
m
e. $80,000 or greater
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What level of measurement is this income variable? Does the income variable
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mfollo w the rules outlined in Figure 1-1? Provide a rationale for your
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manswer.
Answer: In this example, the income variable is measured at the ordinal level. The income
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mcatego-
ries are exhaustive, ranging from less than $50,000 to greater than $80,000. The
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mtwo op en-ended m m
,AG 1-1
m
, AG 1-2 m Answer Guidelines for Questions to Be Graded m m m m m m
categories ensure that all salary levels are covered. The categories are not exclusive, sinc m m m m m m m m m m m m m
me catego- m
ries (d) and (e) include an $80,000 salary, so study participants making $80,000
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mmigh t mark either (d) or (e) or both categories, resulting in erroneous data.
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mCategory (e) c ould be changed to greater than $80,000, making the categories m m m m m m m m m m m m
mexclusive. The categor ies can be rank ordered from the lowest salary to the m m m m m m m m m m m m m
mhighest salary, which is consiste nt with ordinal data (Grove & Gray, 2019; m m m m m m m m m m m m
mWaltz et al., 2017). m m m
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
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26- item Likert scale developed to measure depression in cardiac patients. Study
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participant s rated their symp-
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toms on a scale of 1 to 7, with higher numbers indicating increased severity in the
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depression symptoms. The total scores for each subject obtained from this multi-
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item scale are considered to be at the interval level of measurement (Gray et al., 2017
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; Waltz et al., 2017).
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5. Were nonparametric or parametric analysis techniques used to analyze the
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CDS sc ores for the cardiac patients in this study? Provide a rationale for
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your answer. Answer: Parametric statistics, such as mean and SD, were conducted
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to describe CDS scores
m m for study participants (see Table 1). CDS scores are m m m m m m m m m m
interval-
m
level data as indicated in Questions 5, so parametric statistics are appropriate for this le
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vel of data (Gray et al., 2017; Kim & Mallory, 2017).
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7. Is the prevalence of depression linked to the NYHA class? Discuss the clinical
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im portance of this result.
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Answer: The study narrative indicated that the prevalence of depression increased with m m m m m m m m m m m
the greater NYHA class. In NYHA class III, 64% of the subjects were depressed,
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where as 11% of the subjects were depressed in NYHA class I. Thus, as the NYHA
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class incr eased, the number of sub-
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jects with depression increased. This is an expected finding because as the NYHA
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class increases, cardiac patients have more severe physical symptoms, which usually
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result in emotional distress, such as depression. Nurses need to actively assess cardiac patients
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for depression, especially those in higher NYHA classes, so they might be diagnosed
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and treated as needed.
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8. What frequency and percent of cardiac patients in this study were not being
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trea ted with an antidepressant? Show your calculations and round your answer to the
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nearest whole percent (%).
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Answer: A total of 106 cardiac patients participated in this study. The sample m m m m m m m m m m m m
inc luded 15 patients who were receiving an antidepressant (see Table 1).
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The numb er of cardiac patients not treated for depression was 91 (106 –
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15 = 91). The group percent is calculated by the following formula: (group
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frequ ency ÷ total sample size) × 100%. For this study, (91 patients ÷ 106
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sample siz e) × 100% = 0.858 × 100% = 85.8% = 86%. The final answer is
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rounded to t he nearest whole percent as directed in the question. You could
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have also subtracte d the 14% of patients treated with antidepressants from 100%
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and obtained the 86% who were not treated with an antidepressant.
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t. What was the purpose of the 5-
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minute walk test (5MWT)? Would the 5MWT be useful in clinical practice? m m m m m m m m m m m
Answer: Ha et al. (2018) stated, “The 6- m m m m m m m
min walk test (6MWT) is a measure of the submaximal, steady-
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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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