title: The randomized clinical trial as a powerful means for understanding treatment efficacy.
abstract: The comparison of technologies, ie, alternative ways to accomplish the same aim, is inherently difficult. In orthodontics, technology covers a wide spectrum of areas: variations in treatment approach, appliances, wires, diagnostic procedures, and patient management techniques. Clinical trial methodology has been developed to minimize the effect of bias and to provide more objective answers to questions of comparative efficacy and benefits of particular treatments or procedures. The randomized controlled clinical trial (RCT) is now generally considered the strongest research design for the comparison of treatments. This report reviews four issues that should be addressed in planning an RCT: defining the study cohort, selecting the treatment allocation technique, estimating sample size, and performing the trial.
authors.affiliation: Department of Orthodontics, University of North Carolina, School of Dentistry, Chapel Hill 27599-7450, USA.
authors.forename: C
authors.initials: C
authors.lastname: Phillips
authors.forename: J F
authors.initials: JF
authors.lastname: Tulloch
mesh_terms: D003627:Data Interpretation, Statistical; D018865:Dental Research / Q000379:methods; D006801:Humans; D009971:Orthodontics, Corrective / Q000379:methods*; D018579:Patient Selection; D011446:Prospective Studies; D016032:Randomized Controlled Trials as Topic; D012107:Research Design; D018401:Sample Size; D015983:Selection Bias