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Pandis N, Fleming PS, Hopewell S, Altman DG The CONSORT Statement: application within and adaptations for orthodontic trials. Am J Orthod Dentofacial Orthop. 2015; 147:663-679
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A very brief guide on how to read a report of an orthodontic clinical trial

From Volume 16, Issue 2, April 2023 | Pages 63-66


Kevin O'Brien


Emeritus Professor of Orthodontics, University of Manchester

Articles by Kevin O'Brien

Email Kevin O'Brien


Clinical trials are the accepted benchmark in the assessment of comparative effectiveness of clinical interventions. They should represent a ‘fair test’, being less exposed to the effects of bias and confounding, which risk blurring the effects of an intervention or, indeed, in prompting misleading inferences. In this short article, we summarize some of the key considerations to assist with the appraisal of clinical trial reports. In particular, we focus on aspects relating both to the conduct and reporting of orthodontic clinical trials.

CPD/Clinical Relevance: Clinical trials are pivotal in informing evidence-based practice. We highlight key features that should be considered in relation to the interpretation of orthodontic trial reports.


In this short article, we hope to outline some tips to assist with efficient and effective interpretation of a randomized controlled trial. We have based this on our own experience of interpreting the orthodontic literature. However, we do not intend this to be an extensive analysis of the critical appraisal literature. In-depth papers and texts documenting both the interpretation and appraisal of clinical trials have already been published.1,2

It is widely acknowledged that the randomized controlled trial provides us with high levels of scientific evidence. Trials are designed to minimize bias and the effects of confounding. It is important to note that non-randomized studies may be considered complementary, being better suited to answer certain questions, while also potentially informing trial design and feasibility.3,4 However, a trial is only as good as a paper that reports on its methods and findings, with research waste pervasive across the biomedical literature.5 If the paper is not written clearly, and does not include all the information we need, its value may be limited. In this respect, research methodologists and statisticians have developed an accepted formula for presenting clinical trial methods, which has been outlined in the CONSORT Statement.6 This is an excellent reporting guide, but it is also a great learning resource. An orthodontic version of this has been published to help with orthodontic aspects of trial reporting and interpretation.7 Authors are encouraged to include all of these points in a trial report to ensure that the methodology is transparent, while also allowing detailed appraisal. We have selected several of these points as a framework for ‘how to read an orthodontic clinical trial.’

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