title: Longitudinal randomised controlled trials in rehabilitation post-stroke: a systematic review on the quality of reporting and use of baseline outcome values.
abstract: BACKGROUND
  The World Health Organisation stresses the need to collect high quality longitudinal data on rehabilitation and to improve the comparability between studies. This implies using all the information available and transparent reporting. We therefore investigated the quality of reported or planned randomised controlled trials on rehabilitation post-stroke with a repeated measure of physical functioning, provided recommendations on the presentation of results using regression parameters, and focused on the difficulties of adjustment for baseline outcome measures.
  
  
  METHODS
  We performed a systematic review of the literature from 2011 to 2013 and collected information on the way data was analysed. Moreover we described various approaches to analyse the data using mixed models illustrated with real data.
  
  
  RESULTS
  Eighty-four eligible studies were identified of which 61% (51/84) failed to analyse the data longitudinally. Moreover, for 30% (25/83) the method for adjustment for baseline is not known or not existent. Using real data we were able to show how much difference in results an adjustment for baseline data can make. We showed how to provide interpretable intervention effects using regression coefficients while making use of all the information available in the data.
  
  
  CONCLUSIONS
  Our review showed that improvements were needed in the analysis of longitudinal trials in rehabilitation post-stroke in order to maximise the use of collected data and improve comparability between studies. Reporting fully the method used (including baseline adjustment) and using methods like mixed models could easily achieve this.
authors.affiliation: AG Epidemiology & International Public Health, School of Public Health, Bielefeld University, PO. Box 10 01 31, 33501, Bielefeld, Germany. odile.sauzet@uni-bielefeld.de.
authors.forename: Odile
authors.initials: O
authors.lastname: Sauzet
authors.affiliation: AG Epidemiology & International Public Health, School of Public Health, Bielefeld University, PO. Box 10 01 31, 33501, Bielefeld, Germany. Maren.kleine@uni-bielefeld.de.
authors.forename: Maren
authors.initials: M
authors.lastname: Kleine
authors.affiliation: Faculty of Nursing and Health, University of Applied Science, Münster, Leonardo Campus 8, 48149, Münster, Germany. menzel-begemann@fh-muenster.de.
authors.forename: Anke
authors.initials: A
authors.lastname: Menzel-Begemann
authors.affiliation: AG Epidemiology & International Public Health, School of Public Health, Bielefeld University, PO. Box 10 01 31, 33501, Bielefeld, Germany. anne-kathrin.exner@uni-bielefeld.de.
authors.forename: Anne-Kathrin
authors.initials: AK
authors.lastname: Exner
mesh_terms: D006801:Humans; D017063:Outcome Assessment, Health Care; D016032:Randomized Controlled Trials as Topic; D000071939:Stroke Rehabilitation