Inclusion and exclusion criteria for study participation

Inclusion criteria : A child and his or her parent(s) may be able to participate in the study if:

• The child is between the ages of 7 and 17.
• The child experienced at least three episodes of abdominal pain over a three month period which affected the child’s activities.
• The primary caregiver is willing and able to complete the questionnaires.
• The child lived with the primary caregiver full-time for at least the past two years and for at least half of his or her lifetime.
• The child and the parents consent to participate in the study after receiving details from a research team member.

Exclusion criteria : A child and his or her parent(s) cannot participate in the study if:

• The child has positive physical or laboratory findings which would explain their abdominal pain.
• The child has a chronic disease (e.g. Crohn’s, ulcerative colitis, pancreatitis, diabetes, epilepsy, etc.).
• The child has lactose intolerance as diagnosed by the attending physician.
• The child has undergone major surgery in the past year.
• The child has developmental disabilities that require full-time special education or that impair ability to respond.
• The child or his/her primary caregiver is not able to understand, read or write English.