Criteria

Rome IV criteria

An international consensus framework that defines functional gastrointestinal disorders, including functional diarrhea in infants and toddlers.

Criteria not met

1 stool pattern + 1 duration + 1 onset + 1 growth

Stool pattern

Daily, painless, recurrent passage of at least four large, unformed stools

Duration

Symptoms lasting more than four weeks

Age at onset

Onset between 6 and 60 months of age

Growth

No failure to thrive when caloric intake is adequate

Educational use only. Guideline: Rome IV 2016. Source: Childhood functional gastrointestinal disorders: neonate/toddler, Benninga MA, Faure C, Hyman PE, St James Roberts I, Schechter NL, Nurko S, Gastroenterology, 2016; Rome IV Criteria, Rome Foundation, https://theromefoundation.org/rome-iv/rome-iv-criteria/.

Rome IV gives consensus definitions for functional gastrointestinal disorders, with criteria adapted to age and disorder. The set for functional diarrhea in infants and toddlers combines a characteristic stool pattern with symptom duration, age at onset, and preserved growth when intake is adequate. Because every element must be present, the diagnosis is a defined clinical pattern rather than a label for any frequent loose stools.