First of all it is important to highlight that it is possible to properly speak about continence only in children who completed toilet training: a report prepared for the Agency for Healthcare Research and Quality (AHRQ) of the U.S. Department of Health and Human Services (2006) suggested that most children between the ages of 18 and 30 months have the prerequisite skills to begin toilet training, and Brazelton et al. (1999) found that most children complete toilet training when 36 months old.