A waste of research?

As evidence-based practitioners, readers of Dental Update will be aware of the hierarchy of evidence, but, by way of revision, it is reproduced in Figure 1. It does not mean that in vitro research is worthless. It can be a pointer to, for example, the performance of a given material under loading, but laboratory research cannot accurately predict how that material will perform under the challenging conditions in the mouth. This may raise the question as to nuanced differences between medicine and dentistry when it comes to the hierarchy of evidence: could expert opinion be more important in dentistry than perhaps in medical disciplines? At the upper end of the hierarchy are meta-analyses and systematic reviews, the supposed gold standards. But, how gold are these? A recent letter in the British Dental Journal¹ highlighted the effort going into reviewing primary research, and the idea of an inverted pyramid with a clinical research study being subsequently reviewed and critiqued by numerous individuals who subsequently have their review reviewed and critiqued. There is a real risk this will dissuade busy clinicians from taking part in research, particularly in primary care, where, of course, most dentistry is actually carried out. Much as an in vitro study cannot indicate how a material may behave in the mouth, clinical studies that take place in dental schools and hospitals may not accurately reflect what can be achieved in practice. As alluded to in previous Dental Update Editorials, dentistry needs more research to be carried out in primary care, but if seasoned researchers can't get it right, based on outcomes of systematic reviews, what chance have clinicians in general dental practices? Tips for incorporating research into practice have recently been published,² but taking part in research may be far down the priority list for busy practitioners.