Validation of the pediatric Rome II criteria for functional gastrointestinal disorders using the questionnaire on pediatric gastrointestinal symptoms.

OBJECTIVE: To validate the pediatric Rome II criteria for functional gastrointestinal disorders (FGIDs) using the Questionnaire on Pediatric Gastrointestinal Symptoms (QPGS).
METHODS: Subjects were 315 consecutive new patients, 4 to 18 years of age, seen in a tertiary care clinic and classified by pediatric gastroenterologists as having a functional problem. Patients and parents separately completed the QPGS before medical consultation. Diagnoses were derived using computer algorithms reflecting the Rome II criteria for pediatric FGIDs. Convergent validity was assessed by prevalence of diagnoses and internal validity using factor analysis to confirm symptom clusters of the criteria. Separate analyses were performed for 4 to 9 and 10 to 18 year olds, and for diagnoses based on parent and child reports.
RESULTS: In both age groups, the most prevalent diagnoses were irritable bowel syndrome (IBS) (22.0%, 35.5%), functional constipation (19.0%, 15.2%), and functional dyspepsia (FD) (13.6%, 10.1%). Parent-child concordance on diagnoses was generally poor. Factor analyses supported the internal validity of FD and of IBS symptoms except for relief with defecation. Although functional abdominal pain syndrome and abdominal migraine occurred rarely, symptom clustering within each diagnosis supports their validity. Among patients with abdominal pain, duration was of at least 3 months in most, and pain was of long duration and severe in at least one third.
CONCLUSION: More than half of patients classified as having a functional problem met at least one pediatric Rome II diagnosis for FGIDs. This study offers initial support for the validity of several of the criteria.