OBJECTIVES:The Rome III criteria for irritable bowel syndrome (IBS) are recommended by guidelines to help identify the syndrome. The majority of IBS patients are managed in primary care, where a pragmatic approach to diagnosis is usually adopted, using clinical judgment and knowledge about the patient. Many general practitioners (GPs) have no or limited knowledge of the diagnostic criteria, few use them, and many consider IBS a diagnosis of exclusion. The aim of this study is to explore the sensitivity of the Rome III criteria in relation to a GP-based clinical diagnosis of IBS, to identify differences between Rome III-positive and -negative patients, and to describe the agreement between the various symptom-based criteria.METHODS:Patients aged 18-50 years, presenting in primary care with gastrointestinal complaints and identified as IBS patients by their GP, were referred for enrollment. The Manning and Rome I-III criteria were evaluated through interviews and patients completed the questionnaires The Gastrointestinal Symptom Rating Scale (GSRS)/The Gastrointestinal Symptom Rating Scale modified for use in patients with IBS (GSRS-IBS), Short Form 36, Irritable Bowel Syndrome Quality of Life measurement, Work Productivity and Activity Impairment questionnaire - irritable bowel version, and a questionnaire on use of health-care resources.RESULTS:A total of 604 patients were referred and 499 were included (mean age 32.8 (s.d. 9.5) years, 75% were female). The Rome III criteria were fulfilled by 376 patients (sensitivity 0.75, 95% CI 71-79%). Rome III-positive patients more frequently reported disturbed defecation, had a higher symptom burden, and lower disease-specific health-related quality of life compared with Rome III-negative patients. The various symptom-based criteria identified slightly different subpopulations with the highest agreement between the Rome II and III criteria.CONCLUSIONS:The Rome III criteria identified three in four patients labeled with IBS in primary care. The relevance of the Rome III for IBS in primary care is supported.