title: Informing efficient randomised controlled trials: exploration of challenges in developing progression criteria for internal pilot studies.
abstract: Designing studies with an internal pilot phase may optimise the use of pilot work to inform more efficient randomised controlled trials (RCTs). Careful selection of preagreed decision or 'progression' criteria at the juncture between the internal pilot and main trial phases provides a valuable opportunity to evaluate the likely success of the main trial and optimise its design or, if necessary, to make the decision not to proceed with the main trial. Guidance on the appropriate selection and application of progression criteria is, however, lacking. This paper outlines the key issues to consider in the optimal development and review of operational progression criteria for RCTs with an internal pilot phase.
  
  
  
  A structured literature review and exploration of stakeholders' opinions at a Medical Research Council (MRC) Hubs for Trials Methodology Research workshop. Key stakeholders included triallists, methodologists, statisticians and funders.
  
  
  
  There is considerable variation in the use of progression criteria for RCTs with an internal pilot phase, although 3 common issues predominate: trial recruitment, protocol adherence and outcome data. Detailed and systematic reporting around the decision-making process for stopping, amending or proceeding to a main trial is uncommon, which may hamper understanding in the research community about the appropriate and optimal use of RCTs with an internal pilot phase. 10 top tips for the development, use and reporting of progression criteria for internal pilot studies are presented.
  
  
  
  Systematic and transparent reporting of the design, results and evaluation of internal pilot trials in the literature should be encouraged in order to facilitate understanding in the research community and to inform future trials.
authors.affiliation: Medical Research Council ConDuCT-II Hub for Trials Methodology Research, School of Social and Community Medicine, University of Bristol, Bristol, UK.
authors.forename: Kerry N L
authors.identifier: 0000-0001-5477-2418
authors.initials: KN
authors.lastname: Avery
authors.affiliation: Medical Research Council North West Hub for Trials Methodology Research, Department of Biostatistics, University of Liverpool, Liverpool, UK.
authors.forename: Paula R
authors.initials: PR
authors.lastname: Williamson
authors.affiliation: Medical Research Council North West Hub for Trials Methodology Research, Department of Biostatistics, University of Liverpool, Liverpool, UK.
authors.forename: Carrol
authors.initials: C
authors.lastname: Gamble
authors.affiliation: Medical Research Council ConDuCT-II Hub for Trials Methodology Research, School of Social and Community Medicine, University of Bristol, Bristol, UK.
authors.forename: Elaine
authors.initials: E
authors.lastname: O'Connell Francischetto
authors.affiliation: Medical Research Council ConDuCT-II Hub for Trials Methodology Research, School of Social and Community Medicine, University of Bristol, Bristol, UK.
authors.forename: Chris
authors.initials: C
authors.lastname: Metcalfe
authors.affiliation: National Institute for Health Research Evaluation, Trials and Studies Coordinating Centre, University of Southampton, Southampton, UK.
authors.forename: Peter
authors.initials: P
authors.lastname: Davidson
authors.affiliation: Centre of Evidence-Based Dermatology, University of Nottingham, Queen's Medical Centre, Nottingham University Hospitals NHS Trust, Nottingham, UK.
authors.forename: Hywel
authors.initials: H
authors.lastname: Williams
authors.affiliation: Medical Research Council ConDuCT-II Hub for Trials Methodology Research, School of Social and Community Medicine, University of Bristol, Bristol, UK.|Division of Surgery, Head and Neck, University Hospitals Bristol NHS Foundation Trust, Bristol, UK.
authors.forename: Jane M
authors.initials: JM
authors.lastname: Blazeby
mesh_terms: D001290:Attitude; D002985:Clinical Protocols; D026661:Clinical Trials Data Monitoring Committees; D003657:Decision Making; D019983:Guideline Adherence; D006801:Humans; D017063:Outcome Assessment, Health Care; D018579:Patient Selection; D010865:Pilot Projects; D016032:Randomized Controlled Trials as Topic / Q000379:methods*; D012107:Research Design; D012108:Research Personnel; D058028:Research Report
keywords: STATISTICS & RESEARCH METHODS