Chapter 4: Systematic Reviews of Text and Opinion

Abstract

An evidence-based healthcare approach plays a major role in the clinical decision-making process. Every decision made by a healthcare professional should be based on the best available evidence, clinical experience and patient preferences. The best available evidence is usually understood as statistically proven results of primary or secondary quantitative study. Over the last three decades, results from qualitative studies have also been considered as scientific evidence. However, in the absence of evidence derived from rigorous primary research studies, what are the options? What is the best available evidence when quantitative and qualitative studies are missing? Expert opinion has a role to play in evidence-based health care, as it can be used to either complement empirical evidence or, in the absence of research studies, stand alone as the best available evidence. While rightly claimed not to be a product of ‘good’ science, expert opinion is empirically derived and mediated through the cognitive processes of practitioners who have been typically trained in scientific method. This is not to say that the superior quality of evidence derived from rigorous research is to be denied; rather, that in its absence, it is not appropriate to discount expert opinion as non-evidence. (The Joanna Briggs Institute, 2014) Text and opinion-based evidence (which may also be referred to as non-research evidence) is drawn from expert opinions, consensus, current discourse, comments, assumptions or assertions that appear in various journals, magazines, monographs and reports. (The Joanna Briggs Institute, 2014)(Sackett et al, 1996)(Tonelli, 2006)(Woolf, 2006) An important feature of using opinion in evidence based practice “is to be explicit when opinion is used so that readers understand the basis for the recommendations and can make their own judgment about validity.” (Woolf 2000, p.364) It is also important to highlight that one expert opinion is not as valid as a synthesis of the opinion of a group of experts, as displayed in the formation of consensus guidelines