Validating Simple Modifications to the Rome IV Criteria for the Diagnosis of Irritable Bowel Syndrome in Secondary Care

Abstract

Background: The Rome IV criteria for irritable bowel syndrome (IBS) may be too restrictive for clinical practice and research. Aims: To validate the Rome IV criteria and study the diagnostic performance of simple modifications to them. Methods: We collected symptom data from consecutive adults with suspected IBS seen in a single clinic. We used a reference standard to confirm IBS (presence of lower abdominal pain associated with altered stool form or frequency; no evidence of organic gastrointestinal disease after limited investigation). We applied Rome IV criteria, but also two modifications. First, we re-incorporated abdominal discomfort but kept symptom frequency required for both abdominal pain and discomfort to at least 1 day per week. Second, we included only abdominal pain but relaxed symptom frequency back to 3 days per month. We calculated sensitivity, specificity and positive and negative likelihood ratios (LRs), with 95% confidence intervals (CIs), for each diagnostic criterion. Results: We recruited 170 patients (76.5% female, mean age 37.9 years). Sensitivity and specificity of the Rome IV criteria were 82.1% and 85.1%, respectively; positive and negative LRs were 5.51 (95% CI 2.95–11.3) and 0.21 (95% CI 0.14–0.31), respectively. Modifying the criteria by relaxing the frequency of abdominal pain to 3 days per month led to the best performance [sensitivity 90.2%, specificity 85.1%, positive LR 6.06 (95% CI 3.25–12.2), and negative LR 0.11 (95% CI 0.07–0.19)]. Conclusions: The Rome IV criteria performed well in diagnosing IBS. A simple modification relaxing the required frequency of abdominal pain improved their performance.