Ian Stevenson found that the best research evidence supporting the belief in reincarnation comes from the cases of young children who, typically between the ages of 2 and 5, make statements about a previous life they claim to have had before being born. Some 35 per cent of the children also have birthmarks or birth defects which often correspond to injuries or illness experienced by the deceased person who the subject remembers. Medical documents have confirmed this correspondence in more than forty cases.