title: Descending pain modulation in irritable bowel syndrome (IBS): a systematic review and meta-analysis.
abstract: BACKGROUND
  Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder. While abdominal pain is a dominant symptom of IBS, many sufferers also report widespread hypersensitivity and present with other chronic pain conditions. The presence of widespread hypersensitivity and extra-intestinal pain conditions suggests central nervous dysfunction. While central nervous system dysfunction may involve the spinal cord (central sensitisation) and brain, this review will focus on one brain mechanism, descending pain modulation.
  
  
  METHODS
  We will conduct a comprehensive search for the articles indexed in the databases Ovid MEDLINE, Ovid Embase, Ovid PsycINFO and Cochrane Central Register of Controlled Trial (CENTRAL) from their inception to August 2015, that report on any aspect of descending pain modulation in irritable bowel syndrome. Two independent reviewers will screen studies for eligibility, assess risk of bias and extract relevant data. Results will be tabulated and, if possible, a meta-analysis will be carried out.
  
  
  CONCLUSIONS
  The systematic review outlined in this protocol aims to summarise current knowledge regarding descending pain modulation in IBS.
  
  
  BACKGROUND
  PROSPERO CRD42015024284.
authors.affiliation: Sydney Medical School Northern, University of Sydney, Sydney, NSW, Australia. rosemary.chakiath@sydney.edu.au.|Pain Management Research Institute, Kolling Institute, Northern Sydney Local Health District, St Leonards, Sydney, NSW, Australia. rosemary.chakiath@sydney.edu.au.
authors.forename: Rosemary J
authors.initials: RJ
authors.lastname: Chakiath
authors.affiliation: Sydney Medical School Northern, University of Sydney, Sydney, NSW, Australia. psiddall@hammond.com.au.|Department of Pain Management, HammondCare, Greenwich Hospital, Sydney, NSW, Australia. psiddall@hammond.com.au.|Kolling Institute of Medical Research, Royal North Shore Hospital, St Leonards, Sydney, NSW, Australia. psiddall@hammond.com.au.
authors.forename: Philip J
authors.initials: PJ
authors.lastname: Siddall
authors.affiliation: Sydney Medical School Northern, University of Sydney, Sydney, NSW, Australia. john.kellow@sydney.edu.au.|Department of Gastroenterology, Royal North Shore Hospital, St Leonards, Sydney, NSW, Australia. john.kellow@sydney.edu.au.
authors.forename: John E
authors.initials: JE
authors.lastname: Kellow
authors.affiliation: Discipline of Physiotherapy, Department of Health Professions, Faculty of Medicine and Health Sciences, Macquarie University, North Ryde, Sydney, NSW, Australia. julia.hush@mq.edu.au.|The Centre for Physical Health, Macquarie University, North Ryde, Australia. julia.hush@mq.edu.au.
authors.forename: Julia M
authors.initials: JM
authors.lastname: Hush
authors.affiliation: Psychology Department, Macquarie University, North Ryde, Sydney, NSW, Australia. mike.jones@mq.edu.au.
authors.forename: Mike P
authors.initials: MP
authors.lastname: Jones
authors.affiliation: Discipline of Physiotherapy, Department of Health Professions, Faculty of Medicine and Health Sciences, Macquarie University, North Ryde, Sydney, NSW, Australia. anna.marcuzzi@students.mq.edu.au.|The Centre for Physical Health, Macquarie University, North Ryde, Australia. anna.marcuzzi@students.mq.edu.au.
authors.forename: Anna
authors.initials: A
authors.lastname: Marcuzzi
authors.affiliation: Sydney Medical School Northern, University of Sydney, Sydney, NSW, Australia. paul.wrigley@sydney.edu.au.|Pain Management Research Institute, Kolling Institute, Northern Sydney Local Health District, St Leonards, Sydney, NSW, Australia. paul.wrigley@sydney.edu.au.
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Wrigley
mesh_terms: D000293:Adolescent; D000328:Adult; D002490:Central Nervous System / Q000503:physiopathology*; D006801:Humans; D007422:Intestines; D043183:Irritable Bowel Syndrome / Q000150:complications / Q000503:physiopathology*; D010146:Pain / Q000209:etiology*; D012107:Research Design