Nurses need critical appraisal skills when reading research
As published research on wound management struggles to achieve the standards set by the Cochrane Collaboration for literature reviews, nurses must learn how to appraise it to plan patient treatment
The cornerstone of evidence-based wound management practice is the integration of high-quality research evidence into clinical decision-making (Moore and Cowman, 2008). This evidence should be used in combination with clinical judgement and experience to plan the most appropriate patient treatment.
Poorly conducted research will only yield poor results, which have no place within the clinical arena. It was Cochrane, an influential figure in the development of evidence-based practice (EBP), who argued that with limitations in resources and an increasing demand on service delivery, the choice of the most appropriate, effective treatments was paramount to the success of the health service (Levin, 2001). Indeed, Cochrane further argued that the achievements of the health service should be measured on scientific evidence rather than expert opinion or anecdotal evidence alone (Levin, 2001).
A common approach to gaining an understanding of the current thinking on a particular clinical problem is to read published literature reviews on the subject. It is the case, however, that the traditional literature review often lacks a scientific approach to the selection and rejection of material for inclusion. The ultimate challenge lies in determining if there is bias present and, if so, whether this influences the results of the review. Ultimately, this will challenge the confidence one may have in the outcomes of the specific review.
The literature review is used widely in nursing education, research and as a basis for changing practice. Unfortunately, the literature review is all too frequently conducted and presented with gross limitations, the main one being that it fails to evaluate existing literature. Unlike a literature review, a systematic review aims to summarise all the evidence available, published and unpublished, pertaining to a specific healthcare issue. The Cochrane Collaboration is now the world leader in the development, dissemination and maintenance of high-quality, systematic reviews.
However, even this is not without its challenges. Indeed, Mistiaen et al (2004) conducted a search of the Cochrane Database of Systematic Reviews 2002 issue 3 and found 160 completed reviews. Overall the authors found that 60% of the reviews were inconclusive. Either there was no evidence because no studies existed (8.1%), or there was insufficient evidence to support or refute the intervention (51.9%).
In wound care, the challenge of achieving the standards expected by the Cochrane Collaboration has been well debated. Indeed, the argument prevails that the way in which evidence is generated in wound care remains challenging because of difficulties in achieving all of the quality markers of the randomised control trial (RCT). As a result of issues such as inadequate sample sizes, non-blinded outcome assessment, inadequate follow-up and lack of clear descriptions of interventions, wound care research often falls short of expectations.
Gottrup (2006) argues that the foundation of the problem lies in the lack of agreement regarding the conduct of research in wound management, and that the time has arrived for the development of consensus on what parameters are the most important to explore in order to have acceptable evidence. As such, is the RCT the gold standard or are there other methodologies – such as cohort studies – that would provide more robust, clinically applicable evidence for practice?
It seems clear that the appraisal of scientific evidence in wound care is challenging, with many pitfalls apparent that may mask the true nature of the evidence. Nurses should be aware of the potential for bias in the published literature and develop skills in critical appraisal in order to determine whether one may have confidence in what has been read. After all, evidence is more than just the available literature.
Zena Moore, RGN, MSc, FFNMRCSI is on the Health Research Board of Ireland and a clinical nursing and midwifery research fellow; Seamus Cowman, PhD, MSc, FFNMRCSI, PG Cert (Adults), Dip N (London), RNT, RGN, RPN, is professor and head of nursing, head of department; both at the Royal College of Surgeons in Ireland, Dublin.
Gottrup, F. (2006) Evidence is a challenge in wound care. International Journal of Lower Extremity Wounds: 5, 74–75.
Levin, A. (2001) The Cochrane Collaboration. Annals of Internal Medicine; 135: 309–312.
Mistiaen, P. et al(2004) The evidence for nursing interventions in the Cochrane database of systematic reviews. Nurse Researcher; 12: 71–80.
Moore, Z., Cowman, S. (2008) The Cochrane Collaboration, systematic reviews and meta analysis. In: Watson, R. et al (eds). Nursing Research: Designs and Methods. London: Churchill Livingstone.