critical appraisal

write your second critical appraisal of the previously assigned article:

Cossette, S., Frasure-Smith, N., Dupuis, J., Juneau, M., & Guertin, M. (2012). Randomized controlled trial of tailored nursing interventions to improve cardiac rehabilitation enrollment. Nursing Research, 61(2), 111-120.
This critical appraisal must be written in narrative format. Use headings for each section of the paper as identified in the guidelines, such as Strengths, Weaknesses, and Evaluation. You can also use subheadings of Problem and Purpose, Literature Review, and so forth as needed to organize your paper. Do not use outline numbers in this paper (i., ii., iii., etc.) or present the paper in outline format. This assignment is worth 100 points.


A. Review the chapters of your textbook (Grove, Burns, & Gray, 2013) and other research sources (i.e., Grove, 2007, articles and assigned readings, discussion board, research textbook from undergraduate program) to determine what is quality research.
B. Compare the steps in this study to criteria established in your textbook or other research sources to determine the study’s strengths and weaknesses. You can use the questions on pages 459-462 in Grove et al. (2013) to help you identify study strengths and weaknesses.
C. Evaluate the study findings using the questions in your text as a guideline (Grove et al., 2013, p. 462).
D. Prepare the critical appraisal using the following guidelines:

? Paper should be a maximum of 15 double-spaced pages of text (excluding reference list).

? Use appropriate documentation and develop a reference list using APA (2010) format.
? Write in a narrative style, not an outline format.
E. Document throughout your paper using your textbooks and other research sources to support the statements you making in your critical appraisal of the article
Format for Critical Appraisal #2
A. Discuss the strengths and/or weaknesses of each part of the study. Compare the steps in the study with published research sources(s) to determine if the step is a strength or weakness and provide a rationale to support your decision. Document throughout. Example: The statistical conclusion design validity is a strength in this study since the researchers consistently implemented the intervention in the study based on a detailed protocol (Grove et al., 2013).

? Purpose/Problem
? Literature review
? Framework
? Objectives, questions, and/or hypotheses
? Definition of variables
? Study design: Strengths and threats in the areas of statistical conclusion validity, internal validity, construct validity, and external validity

? Intervention (if applicable)
? Sampling process
? Measurement methods
? Data collection
? Data analysis
? Discussion Section: Findings, limitations, generalizations, implications for practice, and future research.
B. Develop a final evaluation of the quality of the study. Do not just restate strengths and weaknesses. Discuss:

? Your confidence in the study findings.
? Consistency of this study’s findings with the findings from other studies.
? Readiness of findings for use in practice.
? Contribution of the study to nursing knowledge.
Document your statements with references from nursing research literature and your research textbooks.


Critical Appraisal #2
Strengths and Weaknesses


The research problem is clearly identified in the first paragraphs of the Padula et al.
(2009) study, that disabling symptoms erode the quality of life for heart failure patients who are
living longer, but who are hospitalized repeatedly. The researchers point out that there are
millions of such patients in the United States, making their care a significant healthcare concern,
and a reasonable area for study. The problem clearly states an issue: disabling symptoms that
erode quality of life, for a specific population: heart failure patients: in a particular setting, home
care (Burns & Grove, 2009).
The purpose flows logically from this problem, and includes the independent and
dependent variables and the population to be studied. The study purpose described was feasible
in terms of the expertise of the researchers, the subjects and facilities available, and the ethical
considerations given the subjects (Burns & Grove, 2007). The purpose could have been
strengthened by more firmly linking the independent variable of inspiratory muscle training
(IMT) to heart failure. It is discussed as being effective in COPD diagnoses and the physiological
basis of heart failure symptoms is fully discussed. A relational statement is then made that
because heart failure is like COPD physiologically, it is also alike in terms of quality of life
measures for patients suffering from the disease processes, without fully linking the inference
made (Burns & Grove, 2009).

Literature Review

The literature review is organized logically to show the progression of research and a
clear direction of that research. The limitations, theory, and knowledge gleaned from the
previous eight studies reviewed is concisely presented and easily followed to the purpose and
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hypothesis for the Padula et al. (2009) study. A final summary of the literature clarifies what is
known about the subject, and identifies the gaps in knowledge (Burns & Grove, 2009).
The research reviewed, though it is within the previous one to fifteen years of the study,
discusses only three studies within the previous five years, the most recent being three years
before the Padula et al. (2009) study. If more recent research could have been included it would
help the chronology presented. Another weakness of the review is the reliance on empirical
literature; had the researchers included more theoretical literature, perhaps they would have
found more research, and more recent research, that added to the knowledge base (Burns &
Grove, 2009).


The study (Padula et al. 2009) has a clearly identified framework, Bandura’s (1994)
substantive theory of Self-Efficacy from the field of psychology. The aims of the study are
linked to this theory in the discussion of the framework, the variables, and the study design. It is
closely linked to the nursing interventions described within the study, incorporating empirically
verified ways to increase self-efficacy (performance accomplishment, vicarious experiences,
verbal persuasion, and enactive attainment) (Padula et al., 2009, p.19), into the actions of the
nurse with both the intervention and control groups (Burns & Grove, 2007).
The operational definitions of all variables are clearly defined; however, this study could
have been strengthened by more clearly articulated conceptual definitions. Without them, it is
difficult to connect the theory to the variables to the study data, and follow the researchers’ chain
of logic from the theory of self-efficacy to the interventions in the study (Burns & Grove, 2009).
Critical Appraisal #2

Objectives, Questions, Hypotheses

The hypothesis, that nurse- guided IMT training will improve symptoms and perceptions
of quality of life for heart failure patients, is clearly stated, as is the research question, which asks
if a home-based IMT program is effective in increasing IM strength and quality of life measures
for heart failure patients. (Padula et al. 2009, p.18) They include relationships between
independent and dependent variables, and both the research question and the hypothesis relate
back to the quasi-experimental design, which strengthens the study. It is clear what the
researchers intend to study and what they expect to find (Burns & Grove, 2009).
The research question and hypothesis could have been improved by clearly linking them
to the theory of self-efficacy. Although self-efficacy is part of the wording of the research
question, it is not clearly defined how the question or hypothesis link back to the framework of
the study (Burns & Grove, 2009).

Definition of Variables

The operational definitions of the independent and dependent variables are very clearly
explained in the Padula et al. (2009) study and link to back to the hypothesis , purpose, and
problem that includes the relationships between them (Robinson, 2001). However, the lack of
conceptual definitions should have been addressed, in order to delineate the relationships of the
variables to the framework and create a logical flow of ideas from the framework to the

Study Design

The researchers identified threats to validity of the study, such as testing effect, and
equivalence, and included measures taken to minimize those threats. The attrition rate of 6.2%
was well under the 25% minimum, and discussion of reasons for attrition was thorough, which

strengthens this study’s design (Burns & Grove, 2009). The random assignment of groups
minimized selection bias and the quasi-experimental design is appropriate to the stated purpose
and hypothesis. The study was reviewed and approved by three institutional review boards and
consent was obtained from the subjects, so it is ethical (Burns & Grove, 2007).
Because the study is conducted in a natural setting, there is some lack of control that
could threaten the validity of the findings; there is also a history threat to internal validity, due to
HIPPA regulations which were enacted during the period of the study. Though this is mentioned
by the researchers, it is unclear how the HIPPA constraints impacted data collection and
reporting. If it impacted the study data as heavily as the healthcare industry as a whole, the threat
might have been significant (Olsen, 2003). There is also a construct validity threat to the study
because the operational and conceptual definitions were not linked well, and this is again an
instance where the study as a whole could have benefited from clearer conceptual definitions. A
further weakness is that because some random heterogeneity exists in the groups, causation in
the relationships could be affected. The researchers might have considered matching the groups
for variables that might effect treatment such as age, weight, and ejection fraction, since a larger
variation in these factors in one group versus the other might account for some of the differences
noted in outcomes (Burns & Grove, 2009).
The intervention implementation is clearly defined and discussed, and the training of the
research assistants (RA’s) is also detailed. The same RA collected data from the same subjects
to promote consistency or reliability in the data collection process. In addition, the researchers
conducted integrity checks to determine the reliability of the data collection process and also
examined if the RA’s were consistently following the intervention protocol set up for the study.

Critical Appraisal #2
The procedural consistency of the intervention was a strength of the study as the RA’s followed
the structured protocol in implementing the intervention. The study intervention was also linked
to the concepts of Bandura’s theory of self-efficacy, the study framework (Burns & Grove,

Sampling Process

The sampling process was conducted to focus on particular patient population, that of
adult, community-dwelling, stable heart failure patients. Strengths of the process include that the
refusal to participate rate was negligible at less than 2%, and the sample population
demographics were reflective of the demographics of the state population, strengthening the
ability to generalize to a population as a whole (Grove, 2007). Informed consent was obtained
from participants and ethical practice was followed, as it appears no groups were deliberately
excluded from the study.
A major weakness of this study is the lack of a power analysis and power for the study,
making it difficult to determine if the sample size was adequate (Robinson, 2001). The selection
process was also so stringent (only 13.8% of the sample frame was eligible) that results of the
study may not be generalizable to the population of heart failure patients as a whole, since only
thirty two participants were included in this study, out of 288 that were in the sample frame.
Measurement Methods
The measurement methods are well-detailed and seem appropriate to the interventions,
variables, and the ratio/interval and ordinal levels of measurement. Test-retest and concurrent
reliability are reported for the measurement methods used, as are successive use, convergent and
divergent, and content validity, although no values are reported to support this assertion.
Cronbach alpha values were not given for the scales used, with the exception of the COPD SelfCritical

Appraisal #2

efficacy Scale (CSES), which was then modified, and no reliability information was given for
three of the methods used: the Medical Outcomes Short Form (MOS SF 36), the New York
Heart Association (NYHA) classification, and the physiological measurements performed during
physical assessment (Padula et al., 2009, p 23). The lack is a significant weakness of the study,
because it is difficult to determine the actual reliability and validity of the measurement methods,
and therefore to use the conclusions and determine the clinical and statistical significance of
them (Robinson, 2001).
However, inter- rater reliability of the measurement collection itself is well-established.
The primary researcher initially checked that the protocol was used consistently, and checked at
intervals throughout the study. Measures were repeated at pre-defined time points within the
study (weeks one, three, six, nine and twelve), and results correlated, which strengthens
confidence in the measurements reported (Grove, 2007).
Data Collection

The data collection methods are described adequately in the Padula et al. (2009) study.
The research assistants who collected the data were trained and followed a protocol consistently,
in the same way for both the control and intervention groups. Additionally, the same research
assistant collected data on each patient each time, all of which establish consistency of data
collection. The data collected address the hypotheses and research questions: measures of IM
strength, dyspnea, self-efficacy for breathing, and Healthcare Related Quality of Life (HRQOL)
outcomes (Burns & Grove, 2007). If the researchers had included the actual protocol used,
rather than simply describing it, it would have strengthened the confidence in the reliability of
the data collection process, though perhaps the limitations of space prohibited inclusion.
Critical Appraisal #2

Data Analysis

The data analysis is presented in discussion, tables, and figures to make it clearly
understandable. The analysis techniques used were appropriate to the level of measurement of
the variables, ratio/interval and ordinal. Each of the parts of the research question are addressed;
IM strength, dyspnea, self-efficacy for breathing, and Healthcare Related Quality of Life
(HRQOL) outcomes. Significant, non-significant, and serendipitous results are reported and
presented clearly (Burns & Grove, 2009)
A threat to the study is that sample size may be inadequate to detect significant
differences, since no power analysis is given. One effect size of 0.48 for IM strength is given,
but no power analysis is done using this or any other effect size, to determine the degree to
which the IM strength is present in the groups. One scale, the CSES, was found to be inadequate
for measurement due to problems of syntax; validity of the data is further threatened by
monomethod- only one scale type was used to measure HRQOL, for instance (Robinson, 2001).
Discussion Section
Padula et al. (2009) notes the consistency of results of their research with results of
previous research. A strength of their discussion section is the various explanations explored for
their findings, and that they noted limitations in their measurements, namely that the CSES scale
was inadequate as a measurement tool for the data they wished to collect. The researchers
acknowledged that although the primary aims in the research question were answered, the
secondary aims were not, and so did not draw conclusions that were unsupported by the data.
They articulated clearly the data and findings that supported their conclusions: a significant

Critical Appraisal #2

improvement in IM strength and endurance, reported shortness of breath, and dyspnea in the
intervention group, and a discussion of the reasons HRQOL could not be measured adequately.
Their results are strengthened by a low attrition rate, and high compliance rate among patients,
that compared favorably with previous studies (Burns & Grove, 2007).
Padula et al. (2009) does, however, fail to acknowledge a lack of generalizability of their
conclusions: due to small sample size and stringent sampling criteria, there is a limited ability to
generalize to the wider population of heart failure patients. Also, the probability of type II error
is not discussed, either in the forms of a power analysis, or in the narrative (Robinson, 2001).
Their recommendations for future research are including subjects with pulmonary
co- morbidities, tracking the number of doctor and emergency room visits to further investigate
the serendipitous findings of this study, using a different tool to measure self-efficacy, and
examining the effect of varying intensity loads, which correlates with the hypothesis and
purpose, as well as the findings and limitations of this study (Burns & Grove, 2009). While these
are significant directions for future research, the addition of less stringent and more generalizable
sampling criteria, and power analysis to determine optimal sample size would strengthen the
evidence base for IMT.


With so many patients experiencing heart failure living longer lives, the ability to improve
their symptoms and avoid hospitalization is significant to both patients and nurses. The Padula
et al. (2009) study adds to the body of knowledge about this important problem in healthcare.
The strengths of this study outweigh the weaknesses. The weaknesses, in particular the lack of
power analysis and measurement values, could be easily corrected in future studies. While the

Critical Appraisal #2


lack of values for reliability and validity are cause to use the measurements with caution, the
strengths of the overall design, framework, and execution of the interventions provide evidence
of value to nursing practice. IMT training is relatively inexpensive, safe, and could be easily
added to the patient’s home regimen. While the evidence is not strong enough to generalize the
findings to all heart failure patients, certainly as an adjunct to traditional care, IMT has value for
patients with stable class II or III heart failure without co-morbidities (Burns & Grove, 2007).

Consistency with previous research

The findings of this study are consistent with the previous five randomized controlled
trials and the three which were not, which are summarized within the Padula et al. (2009) study.
All of the research found varying levels of increased IM strength, though the results on perceived
quality of life measures and dyspnea were mixed, and the designs of previous studies included
widely varying protocols for IMT frequency, times, and dosing. This study seems to accurately
reflect the value of home-based intervention techniques, which only one previous study had
evaluated, and to improve on previous studies by setting a consistent protocol for data collection
and patient compliance, and integrating self-efficacy theory effectively, particularly mutual goalsetting.
The study also improves on previous designs for its applicability to nursing, by
introducing nurse-coaching as an element in the study intervention. (Burns & Grove 2009).

Readiness of findings for use in practice
The Padula et al. (2009) findings provide good evidence for directing nurse practice for
patients with stable heart failure. Nurse-coached IMT seems to have value for these patients and
regular assessment and telephone contact with the nurse, which could be used in practice, are
strengths of the study. The ease of use of the Threshold device and safety of the protocol make it
easily transferrable to practice, and goal setting and other theory constructs seem to be easily

Critical Appraisal #2
used and taught to most patients within the context of nursing care. However, the researchers do
fail to take into account practicality in terms of time, insurance, and Medicare reimbursement
and patient compliance over time, as a lifelong behavior change may be needed by the patient to
continue the gains of IMT. All of these factors would need to be considered when attempting to
put the interventions into widespread practice. The researchers, in recommending widespread use
of the study intervention have perhaps generalized beyond their sampling criteria. While the
findings may be of use to all heart failure patients, further study is needed before use with
patients who have conditions that differ from the study sample criteria, such as co-morbidities or
more severe disease (Burns & Grove, 2007).
Contribution to Nursing Knowledge
The Padula et al. (2009) study advances nursing knowledge by putting forward another
tool to provide adjunct care for patients with chronic long-term symptoms of heart failure, who
are suffering a diminished quality of life. The study advances the research and provides clear
direction for future research that could further benefit patients and nurses dealing with a
significant, costly public health issue. It advances previous study designs, and provides evidence
that nurse coaching and involvement is a valuable part of the improvement of patient outcomes,
by incorporating them into the purpose, hypothesis, research question, and independent variable
of the study (Burns & Grove, 2009).



critical appraisal