Nursing free essay: Systematic Research Review Critique
Systematic Research Review Critique
Systematic research review (SRR) refers to a summary of evidence derived through gathering, synthesizing and appraising the previous studies to respond to a specific research problem or answer a research question. In evidence-based nursing practice, SRR helps to reduce biases that are present or inherent in individual studies. This paper presents a critical analysis of SRR related to the relationship between the consumption of linoleic acid (LA) and the risk of developing heart attack conducted by Farvid et al. (2014). Heart attack is one of the major causes of admissions for emergency treatment in healthcare settings. Also, heart attack is the leading cause of deaths in the world. The Center for disease Control and Prevention reported in 2015 that cardiac attack is the cause of 1 out of 4 deaths that occur in the US every year. The statistics indicated that around 610,000 deaths that occur annually in the US are caused by heart attack. According to the Center for disease Control and Prevention (2015), around 47 percent of the Americans are exposed to the risk factors for the development of heart attack. The case of the US is replicated in many other parts of the world. One of the suggested ways of reducing the risk of developing heart attack is increasing the consumption of LA (Ringel, Davis & Hibbeln, 2013; Vedtofte et al. 2011). However, results derived from individual studies on the impact of LA have been inconsistent, hence triggering SRRs focusing on the topic. In order to enhance the critical practice further, it is vital to conduct critical analysis of SRRs. This paper contains a critical analysis of research rigor, level of evidence, clarity and overall evidence in the SRR carried out by Farvid et al. (2014).
Critique of Research Rigor
Farvid et al. (2014) started the SRR by describing the research that guided the review. The research question was whether or not LA intake reduces the risk of developing heart disease. The research question helps in narrowing the focus of the SRR. Also, the research question makes it easy for the reader to determine the topic of the SRR and guess the conclusions to expect. As such, the research question helps to increase the connection of the readers’ mind with the SRR. The authors began the review process by searching for research articles containing studies related to their topic of focus from two main databases, namely EMBASE and MEDLINE. The authors also searched for additional articles containing cohort studies focusing on the relationship between LA intake and incidences of heart attack (Farvid et al., 2014).
The authors divided different tasks among themselves in a way that helped to enhance the efficiency of the review process. One of the investigators used specific search terms to identify abstracts and titles of potential articles. Two of the investigators analyzed full texts of the articles identified to determine their relevance to the topic of study. For instance, the investigators explained that they included “prospective cohort studies containing multivariate-adjusted risk estimates….. for dietary LA consumption as the exposure and CHD endpoints”( Farvid et al., 2014, p. 3). The investigators excluded ecological, cross-sectional or retrospective studies, non-original papers such as letters, editorials and reviews, duplicated publications, meeting abstracts, studies on non-adults and studies conducted on individuals with known CDH at baseline. In the cases where differences emerged in the views of the two investigators, a third investigator was asked to intervene. The investigators identified 8782 citations for articles initially and selected 6 articles containing cohort studies eventually. The four investigators worked together to identify 6 additional articles from Pooling Project of Cohort Studies on Diet and Coronary Disease. Ultimately, the investigators added a study related to the topic of focus from Alpha-Tocopherol and Beta-Carotene Cancer Prevention Study. In total, the investigators reviewed 13 articles. The literature review and data extraction processes were carried out by two investigators.
A notable aspect of the SRR, however, is that the investigators did not use a specific level of evidence for the studies included in the inclusion criteria. Probably the investigators failed to do so since the inclusion criteria they selected enabled them to include studies containing significant evidence. Validity of results of studies is highly influenced by biasness (Bemker & Schreiner, 2016). The investigators acknowledged that the validity of their findings could be influenced by biasness in the selected studies. In response, they conducted Begg’s test and visual inspection of funnel plot on the studies selected. As noted in the SRR, the analysis process showed no evidence of significant levels of biasness in the studies included. The results of the SRR are valid considering the nature of the studies included.
Critique of Level of Evidence
As Bemker and Schreiner (2016) explained, the level of evidence in the evidence pyramid is highly influenced by the type of study and the sources of evidence. The 13 studies included in the SRR conducted by Farvid et al. (2014) represent level II of the evidence pyramid since the overall evidence is derived from well designed randomized controlled trials. In the SRR, the investigators include evidence of the search strategy used and the specific details of the 13 articles included in the review. For instance, the investigators include evidence of the results of Israeli Ischemic Heart Disease Study, Women’s Health Study, Västerbotten Intervention Program and Atherosclerosis Risk in Communities Study. The authors also explain the number of participants in each of the studies included.
Critique of Clarity
The SRR conducted by Farvid et al. (2014) is strengthened by high level of clarity in the review strategy that was adopted and evidence of the information that was extracted from the articles selected. The authors represented evidence from the previous studies in theory, figures and tables. The information in theory and some charts is easily readable and understandable. For instance, the investigators used a flow chart to show the number of articles that were identified initially, which was 8782. The flow chart shows a step-by-step process that was used on eliminating the articles that did not qualify until the investigators were left with a final sample of 6 articles. The authors provide demographic information of the participants involved in the selected studies. For instance, the investigators evaluated the findings of 12,535 women and 8139 men involved in the he Malmo Diet and Cancer Cohort study. However, much of the information in the tables and figures that is already synthesized may not be easily understood by the reader. The information can be improved through using full words instead of initials in the tables and figures and giving step-by-step explanations of how the synthesis of information was carried out.
Overall, Farvid et al. (2014) found that dietary LA reduces the risk of occurrence of heart attack by 15 percent “(pooled RR, 0.85; 95% confidence intervals (95% CI): 0.78-0.92; I²=35.5%)” (Farvid et al., 2014, p. 2). The results indicated further that dietary intake reduces the risk of death from heart attack by 21 percent “(pooled RR, 0.79; 95% CI, 0.71-0.89; I²=0.0%)” (Farvid et al., 2014, p. 2). According to the findings of the SRR, 5 percent increase in the intake of LA replacing the intake of saturated fat reduces the risk of the occurrence of heart attack by 9 percent and the risk of death from heart attack by 13 percent. Based on the findings, it is clear that an increase in the intake of LA reduces the risk of heart attack. The main limitation addressed in the study is publication bias. The limitation was important since it could affect the validity of the study results.
Critique and Conclusion
Farvid et al. (2014) carried out an excellent systematic review of the previous studies focusing on the association between dietary intake of LA and the risk of developing a heart attack. Ultimately, the authors made an appropriate conclusion to the research question. The main implication of the SRR is that we should increase dietary intake of LA in order to reduce the probability of getting heart attacks.
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