Trial Forge Guidance 2: how to decide if a further Study Within A Trial (SWAT) is needed.

• Treweek S Health Services Research Unit, University of Aberdeen, Aberdeen, UK. streweek@mac.com.
• Bevan S National Institute for Health Research Evaluation, Trials and Studies Coordinating Centre, Southampton, UK.
• Bower P MRC North West Hub for Trials Methodology Research, Centre for Primary Care and Health Services Research, University of Manchester, Manchester, UK.
• Briel M Department of Clinical Research, Basel Institute for Clinical Epidemiology and Biostatistics, University Hospital Basel and University of Basel, Basel, Switzerland.
• Campbell M Health Services Research Unit, University of Aberdeen, Aberdeen, UK.
• Christie J GSK Medicines Research Centre, Stevenage, UK.
• Collett C Health Research Authority, London, UK.
• Cotton S Health Services Research Unit, University of Aberdeen, Aberdeen, UK.
• Devane D HRB-Trials Methodology Research Network, National University of Ireland Galway, Galway, Ireland.
• El Feky A Health Services Research Unit, University of Aberdeen, Aberdeen, UK.
• Galvin S HRB-Trials Methodology Research Network, National University of Ireland Galway, Galway, Ireland.
• Gardner H Health Services Research Unit, University of Aberdeen, Aberdeen, UK.
• Gillies K Health Services Research Unit, University of Aberdeen, Aberdeen, UK.
• Hood K Centre for Trials Research, College of Biomedical & Life Sciences, Cardiff University, Cardiff, UK.
• Jansen J Division of Acute Care Surgery, University of Alabama at Birmingham, Birmingham, USA.
• Littleford R University of Queensland Centre for Clinical Research, University of Queensland, Brisbane, Australia.
• Parker A York Trials Unit, University of York, York, UK.
• Ramsay C Health Services Research Unit, University of Aberdeen, Aberdeen, UK.
• Restrup L Public and patient representative, Aberdeen, UK.
• Sullivan F School of Medicine, St Andrews University, St Andrews, UK.
• Torgerson D York Trials Unit, University of York, York, UK.
• Tremain L National Institute for Health Research Evaluation, Trials and Studies Coordinating Centre, Southampton, UK.
• von Elm E Cochrane Switzerland, Institute of Social and Preventive Medicine (IUMSP), Lausanne University Hospital, Lausanne, Switzerland.
• Westmore M National Institute for Health Research Evaluation, Trials and Studies Coordinating Centre, Southampton, UK.
• Williams H Centre of Evidence-Based Dermatology, Queen's Medical Centre, Nottingham University Hospitals NHS Trust, Nottingham, UK.
• Williamson PR MRC North West Hub for Trials Methodology Research, Department of Biostatistics University of Liverpool, Liverpool, UK.
• Clarke M Northern Ireland Methodology Hub, Queen's University Belfast, Belfast, UK.

Clinical Decision-Making

Evidence-Based Medicine

Humans

Practice Guidelines as Topic

Randomized Controlled Trials as Topic

Research Design