An examination of data from hospital emergency rooms in the US from 2002 to 2010 indicated that the most common form of toilet training related injury was caused by falling toilet seats, and occurred most often in children aged two to three. The second most common injury was from slipping on floors, and 99% of injuries of all types occurred in the home.: 176 In abusive homes, toilet training may be a trigger for child maltreatment, especially in circumstances where a parent or caregiver feels the child is old enough that they should have already successfully mastered training, and yet the child continues to have accidents.: 311 : 50  This may be misinterpreted by the caregiver as willful disobedience on the part of the child.