Do Most Children with Functional Constipation Meet the Commonly Used Clinical Trial Endpoints?

Background/Objectives: Functional constipation (FC) is diagnosed using the Rome IV criteria, which require at least two of seven symptoms for diagnosis. Clinical trials evaluating FC treatments commonly use bowel movement frequency, stool consistency, and fecal incontinence as primary endpoints. However, there is limited data on whether these endpoints accurately represent the symptom distribution in children with FC. This study assessed the frequency of each criterion in a large children’s community sample to determine whether commonly used clinical trial endpoints accurately reflect symptom distribution. Methods: A cross-sectional study of school children aged 8–18 years was conducted across seven Colombian cities. Participants completed the Pediatric Gastrointestinal Symptoms Rome IV Questionnaire (QPGS-IV). The prevalence of FC and the distribution of diagnostic criteria were analyzed, calculating the percentage of each criterion. Results: 6611 children completed the questionnaires. FC was diagnosed in 12.8% of participants, making it the most common disorder of gut–brain interaction. The most reported criteria were fewer than two stools per week (66.1%) and painful bowel movements (65%), while fecal incontinence was uncommon (6.9%). 60.5% of participants met only two criteria, with two or fewer defecations per week and painful bowel movements being the most common combination. Conclusions: This study reveals significant variability in Rome IV criteria prevalence for FC, highlighting disparities between the most common endpoints in clinical trials and symptom distribution in a community-based cohort. Painful bowel movements emerged as a critical diagnostic component but remain underutilized as an endpoint in pediatric trials. These findings suggest the possible need to reassess endpoint selection in clinical trials.