Introduction
The PICO question that has been considered based on a clinical problem for evidence based nursing practice is- “In patients aged 60 years and above (P), what is the effect of being administered the influenza vaccine (I) on contracting pneumonia (O) compared with not receiving the influenza vaccine (C) during the Flu season (T)?”The present paper discusses each of the resources selected and where they fall within the eight-part evidence hierarchy. Based on the evidence, a conclusion is drawn whether the strength of the evidence is high, moderate or low.
Ranking of evidence
According to LoBiondo-Wood and Haber (2017) hierarchy of evidence of level of evidence in nursing research are assigned on the basis of methodological quality of their validity, design and applicability. The evidence hierarchy acts as a valuable tool that permits researchers to undertake a top-down approach for identifying the best evidence. This eight part hierarchy of evidence has meta-analysis studies at level I and systematic reviews at level II, denoting that these are the two strongest forms of evidences. These are followed by randomized controlled trials, cohort studies, case control studies, case series, expert opinions and animal research studies.
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Figure: Hierarchy of evidence (LoBiondo-Wood &Haber, 2017)
The research conducted by Vila-Corcoles et al., (2016) is a population-based cohort study, investigated the burden of pneumococcal pneumonia on older adults. The study thus falls into level IV evidence category. The study of Ellen (2017) is also a cohort study with data collected through semi-structured interviews for collecting data from nurses focusing on facilitators and facilitators for vaccination. In addition it assessed health care providers' roles in influencing patients to be vaccinated. The study thus falls into level IV evidence category. Restive et al., (2017) carried out a meta-analysis quantifying data that reported influenza vaccine effectiveness (VE) on hospitalizations and influenza visits involving cohort and case control studies carried out with high-risk groups. This study is a part of level I evidence as per the hierarchy of evidence. The study of Kan and Zhang (2018) is a systematic review that explored the behaviour-related factors influencing influenza vaccination in relation to elderly people with the help of the Theory of Reasoned Action (TRA) and the Health Belief Model (HBM). This study is therefore level II evidence.
Strength of evidence
Based on the level of evidences for each study, it is to be concluded that the strength of evidence is moderate since two evidences are level IV, one is level I and one is level II. The strength of evidence would have been high if at least two of the evidences were level I evidence and two others were either level II or level III (LoBiondo-Wood & Haber, 2017).This implies that the evidences are to undergo further scrutiny before considering application in nursing practice.
Conclusion
Nursing evidence based research has the aim of reviewing research studies and grading the quality of the respective articles. Ranking the bodies of evidences as per the hierarchy of evidence is useful for understanding the quality of studies. The strength of evidences addressing the present PICO question is moderate due to the methodologies of the respective studies. In nursing, evidence based research it is advisable to apply evidences of high strength into practice.
References
Ellen, M. (2017). Factors that influence influenza vaccination rates among the elderly: nurses’ perspectives. Journal of nursing management.
Kan, T., & Zhang, J. (2018). Factors influencing seasonal influenza vaccination behaviour among elderly people: a systematic review. Public Health, 156, 67-78.
LoBiondo-Wood, G., & Haber, J. (2017). Nursing Research-E-Book: Methods and Critical Appraisal for Evidence-Based Practice. Elsevier Health Sciences.
Restivo, V., Costantino, C., Bono, S., Maniglia, M., Marchese, V., Ventura, G, Vitale, F. (2017). Influenza vaccine effectiveness among high-risk groups: A systematic literature review and meta-analysis of case-control and cohort studies. Human Vaccines & Immunotherapeutics, 1-12. doi:10.1080/21645515.2017.1321722
Vila-Corcoles, A., Ansa, X., Ochoa-Gondar, O., Satue, E., De Diego, C., & Rodriguez-Blanco, T. (2016). Pneumococcal pneumonia in adults 60 years or older: Incidence, mortality and prevention. Medicina Clínica, 146(5), 199-202. doi:10.1016/j.medcli.2015.09.015