Study design in clinical orthopaedic trials

This article addresses the explicit and salient aspects of clinical orthopaedic trial design for those requiring a concise overview of this topic. Planning and conducting a clinical trial requires an understanding of the key components of study design to appreciate the relative strengths and weaknesses of a particular design in answering a specific research question. At the outset of a research project a mandatory planning phase should produce an effective protocol. This should state the scientific basis of the study and utilize an appropriate study design, addressing the key concepts of validity and reliability. In the context of randomized controlled trials, one must consider how the population of interest is sampled and randomly assigned, the use of a control group and the outcome measures to be employed. In some circumstances other study designs may be preferable and it is important to note their indications so as to limit their misuse.