critical appraisal

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

Critical Appraisal #2


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).

Last Updated on February 11, 2019 by Essay Pro