title: Reported methodological quality of split-mouth studies.
abstract: OBJECTIVE
  Hujoel & Moulton previously questioned the reported quality of split-mouth studies. Since then, there has been little enquiry into the methodology of this study design. The aim was to conduct a systematic review of the reported methodology of clinical studies using a split-mouth design published in dental journals over a 1-year period (2004).
  
  
  METHODS
  An extension of the CONSORT guidelines for cluster-randomized designs was used to evaluate quality. We evaluated the methods used and quality of reporting split-mouth studies.
  
  
  RESULTS
  Thirty-four studies were eligible for this review. The results showed that many papers lack essential qualities of good reporting, e.g. five of 34 papers gave the rationale for choosing a split-mouth design, 19 of 34 (56%) used appropriate analytical statistical methods and only one of 34 presented an appropriate sample size calculation. Of the five studies that used survival analysis, none of them used a paired approach.
  
  
  CONCLUSIONS
  Despite some progress in statistical analysis, if the reporting of studies represents the actual methodology of the trial, this review has identified important aspects of split-mouth study design and analysis that would benefit from development.
authors: Biostatistical Centre, Catholic University Leuven, Leuven, Belgium. emmanuel.lesaffre@med.kuleuven.be
authors: Emmanuel
authors: E
authors: Lesaffre
authors: Maria-José
authors: MJ
authors: Garcia Zattera
authors: Carol
authors: C
authors: Redmond
authors: Heidi
authors: H
authors: Huber
authors: Ian
authors: I
authors: Needleman
mesh_terms: D003627:Data Interpretation, Statistical; D018865:Dental Research / Q000592:standards* / Q000706:statistics & numerical data; D006801:Humans; D016032:Randomized Controlled Trials as Topic / Q000592:standards* / Q000706:statistics & numerical data; D012107:Research Design / Q000592:standards* / Q000706:statistics & numerical data; D018401:Sample Size; D016019:Survival Analysis