title: Validity and reliability of the developmental assessment screening scale.
abstract: OBJECTIVE
  To develop and validate the 6-year Ages and Stages Questionnaire (ASQ) for school-age children.
  
  
  METHODS
  Parents/caregivers of children 66-78 months were recruited from 6 countries and 15 states in the United States. Similar to other ASQ intervals, the 6-year ASQ has five developmental domains targeted for children from 66 months to 78 months of age. We assessed internal consistency reliability, test-retest reliability, the scale structure, validity (correlation coefficients), and utility of the 6-year ASQ. The 6-year ASQ screens development in five domains using 30 items.
  
  
  RESULTS
  Coefficient alpha measuring internal consistency was 0.97. Test-retest reliability was estimated by having parents complete two ASQ's on the same child within a week interval. Correlations between scores of the two ASQ's reflected stability of scores. Test-retest reliability results were robust with an intraclass correlation coefficient of 0.94. Factor analysis results resulted in a five factors structure. The Pearson correlations coefficients between the latent variables were moderate to large and statistically significant, P < 0.0001. The 6-year ASQ screens development in five domains using 30 items. The administration time varied from 10 to 60 min with a mean of 15.17 min. General utility result shows that the 6-year ASQ can be used with satisfaction by caregivers, pediatricians, professionals, and parents.
  
  
  CONCLUSIONS
  Preliminary data on the 6-year ASQ reflected promising results. An easy-to-administer, accurate caregiver-completed screening tool may increase the frequency of screening for school-age children.
authors.affiliation: College of Education and Technology, Eastern New Mexico University, New Mexico, USA.
authors.forename: Ajay
authors.initials: A
authors.lastname: Singh
authors.affiliation: Department of Special Education and Clinical Sciences, College of Education, University of Oregon, Oregon, USA.
authors.forename: Jane
authors.initials: J
authors.lastname: Squires
authors.affiliation: Department of Human Development and Family Science, College of Health and Human Performance, East Carolina University, NC, USA.
authors.forename: Chia Jung
authors.initials: CJ
authors.lastname: Yeh
authors.affiliation: Department of Early Childhood Education, Chongshin University, Seoul, South Korea.
authors.forename: Kay H
authors.initials: KH
authors.lastname: Heo
authors.affiliation: Office of Faculty Excellence, East Carolina University, NC, USA.
authors.forename: Hui
authors.initials: H
authors.lastname: Bian
keywords: Developmental screening; primary care; screening tools