Given the very high overlap between social anxiety disorder and selective mutism (as high as 100% in some studies Despite the change of name from "elective" to "selective", a common misconception remains that a selectively mute child is defiant or stubborn. In fact, children with SM have a lower rate of oppositional behavior than their peers in a school setting. Some previous studies on the subject of selective mutism have been dismissed as containing serious flaws in their design. According to a more recent systematic study it is believed that children who have selective mutism are not more likely than other children to have a history of early trauma or stressful life events. Another recent study by Dummit et al., in 1997 did not find any evidence of trauma in their sample of children. Recent evidence has shown that trauma does not explain why most children with selective mutism develop the condition. Many children who have selective mutism almost always speak confidently in some situations. Children who have experienced trauma however are known to suddenly stop speaking.