Rome III Constipation Criteria:

Two or more of the following must be present  In infant and children up to ages four, these symptoms must be present for at least one month In  children aged over four, symptoms must be present for at least two  months,with insufficient criteriafor the diagnosis of  diagnosis of irritable bowel syndrome

Two or fewer defecations per week

At least one episode per week of faecal incontinence after the child has acquired toileting skills

History of excessive stool retention or retentive posturing

History of painful or hard bowel movements

Presence of large faecal mass rectum

History of stool with a large diameter which may obstruct the toilet