BackgroundFunctional gastrointestinal disorders (FGIDs) are a common, diverse group of disorders of unknown etiology, resulting in significant socieconomic burden. In this study, we aimed to assess the prevalence of FGIDs in children aged 6-18years and examine their association with various demographic and socioeconomic parameters. MethodsThis was a school-based, cross-sectional study approved by the relevant government authorities. Informed consent was obtained by the legal representatives of all children who participated. Diagnoses of FGIDs were based on the Greek official translation of the ROME-III questionnaire. Demographic and socioeconomic information were also collected. Key ResultsA total of 1588 children (51.8% females, mean age: 12.92.8years) were included. The overall prevalence of any-FGID was 23.1% (95% CI: 21.1-25.2). The most common FGIDs were functional constipation, n=231 (13.9%), abdominal migraine, n=84 (5.6%), aerophagia, n=58 (3.5%), and irritable bowel syndrome, n=48 (3.0%). Multiple logistic regression analysis on the probability of any-FGID identified physical exercise, TV-exposure, victimization, gender, parental educational level, number of children at home and number of adults at home as significant covariates for any-FGID in the final model. Conclusions and InferencesFGIDs affect approximately 1 in 4 school-aged children in Greece. The following characteristics are associated with a higher probability of any-FGID: female gender, living in a non-nuclear household, victimization, lower parental education level, infrequent physical activity, and high television exposure.