Systematic reviews are usually undertaken to assess the strength of the available evidence for a particular management approach. The review process allows for data to be extracted from primary studies, and combined to provide an overall picture of available research evidence.
To be credible, the review process needs to be based on a sound search strategy, and strict, transparent inclusion / exclusion criteria for relevant papers relating to the population being investigated, the intervention(s) being examined, and appropriate comparators and outcome measures.
A disappointment in many systematic reviews in allied health is the lack of clear evidence of effectiveness of specific management strategies. This is often related to the paucity of literature available in the area being investigated, and/ or the methodological inadequacies of included studies. These situations often attenuate the evidence for one approach over another and leave the reader dissatisfied, as no clear recommendation can be made.Too often in allied health, systematic reviews conclude with "more research needs to be undertaken," which doesn’t assist in establishing the current best evidence with which to inform practice.
With the increasing number of pragmatic trials being published, where one intervention is compared with another which has equal chance of being effective (rather than comparing an intervention with a placebo, or ineffective control), it will be increasingly common to find systematic reviews which suggest that doing "something" is better than doing "nothing," and "something" could be one of a range of approaches.
One of the reviews (Hillier) published in this edition of the journal makes this claim. In the area of DCD, there seem to be a number of schools of thought about management, as the author found when obtaining feedback from clinicians and researchers on her review.
Children’s health and development is a contentious area, where parents of children with problems may be persuaded to use particular treatments based on evidence of variable strength. This review suggests that there are a number of equally efficacious approaches to manage children with DCD, and that no one treatment approach offers more benefits than another. We hope that you enjoy reading this high quality systematic review, and use the findings to draw your own conclusions.
Grimmer-Somers K. Systematic Reviews. The Internet Journal of Allied Health Sciences and Practice. 2007 Jul 01;5(3), Article 3.