Development and Psychometric Evaluation of a New Instrument for Measuring Sleep Length and Television and Computer Habits of Swedish School-Age Children.
The aim was to develop a new instrument for measuring length of sleep as well as television and computer habits in school-age children. A questionnaire was constructed for use when children visit the school health care unit. Three aspects of the validity of the questionnaire were examined: its face validity, content validity, and construct validity. Test-retest reliability was assessed by giving t