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Irritable Bowel Syndrome (Rome IV diagnostic criteria)

Irritable Bowel Syndrome Diagnosis and Treatment

Recurrent abdominal pain, on average, at least 1 day/week in the last 3 months with symptom onset at least 6 months before diagnosis

Related to defecation?   [e.g. abdominal pain is related to defecation as opposed to the previous criteria - Rome III: improved with defecation].  A significant number of patients with IBS report worsening of pain with defecation.

Associated with a change in frequency of stool?

Associated with a change in form (appearance) of stool?

Updated Diagnostic Criteria - Rome IV

The Rome IV criteria introduced two major changes compared to the previous Rome III criteria. 5,6  The new criteria no longer includes abdominal discomfort as part of the definition of IBS. Abdominal pain is now required  in order to meet the new diagnostic criteria.  Another important change was the change in symptom frequency:

Rome IV: Abdominal pain should be present at least 1 day per week on average during the preceding month.  Rome III:  at least 3 days per month.  The new criteria are not likely to change the incidence of IBS in clinical populations.5 

Access our IBS diagnosis calculator based on the Rome IV criteria

info  The diagnosis of IBS requires not only meeting the diagnostic criteria, but also on a limited number of additional tests based on the symptoms reported.

The Rome IV criteria also redefined the four subtypes of IBS as follows:
  • IBS with constipation (IBS-C):   >25% hard stools and <25% loose stools
  • IBS with diarrhea (IBS-D): >25% loose stools and <25% hard stools
  • IBS with mixed bowel habits (IBS-M):  >25% loose stools and >25% hard stools
  • Unclassified IBS (IBS-U):  <25% loose stools and <25% hard stools.

This new approach is more likely to reflect experience from clinical practice and should substantially reduce the IBS-U group while increasing the IBS-M group.


  1. Simren M,  Palsson OS,  Whitehead WE. Update on Rome IV Criteria for Colorectal Disorders: Implications for Clinical Practice.  Curr Gastroenterol Rep. 2017; 19(4): 15.  Published online 2017 Apr 3. doi: 10.1007/s11894-017-0554-0 PMCID: PMC5378729
  2. Drossman DA. Functional Gastrointestinal Disorders: History, Pathophysiology, Clinical Features and Rome IV. Gastroenterology. 2016;150:1262-1279.

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