Convergent validity of actigraphy with polysomnography and parent reports when measuring sleep in children with Down syndrome.

Our current data suggest that actigraph watches demonstrate convergent validity and are sensitive to measuring certain sleep constructs (duration, efficiency) in children with Down syndrome. However, parent reports, such as the Children's Sleep Habits Questionnaire, may be measuring other sleep constructs. These findings highlight the importance of selecting measures of sleep related to target concerns.