title: Floor effects associated with universal screening and their impact on the early identification of reading disabilities.
abstract: Response to intervention (RTI) holds great promise for the early identification and prevention of reading disabilities. The success of RTI rests in part on the accuracy of universal screening tools used within this framework. Despite advancements, screening instruments designed to identify children at risk for reading disabilities continue to have limited predictive validity. In this study, the authors examined a common screening instrument for the presence of floor effects and investigated the impact that these effects have on the predictive validity of the instrument. Longitudinal data (kindergarten to third grade) from a large cohort of children were used. These data included children's performance on five measures from the Dynamic Indicators of Basic Early Literacy Skills (DIBELS) and two reading achievement outcome measures. The results showed that DIBELS measures were characterized by floor effects in their initial administrations and that these effects reduced the predictive validity of the measures. The implications of these findings for early identification are discussed.
authors.affiliation: University of Kansas, Lawrence, KS 66045, USA. catts@ku.edu
authors.forename: Hugh W
authors.initials: HW
authors.lastname: Catts
authors.forename: Yaacov
authors.initials: Y
authors.lastname: Petscher
authors.forename: Christopher
authors.initials: C
authors.lastname: Schatschneider
authors.forename: Mindy
authors.initials: M
authors.lastname: Sittner Bridges
authors.forename: Katherin
authors.initials: K
authors.lastname: Mendoza
mesh_terms: D001741:Black or African American / Q000706:statistics & numerical data; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D004410:Dyslexia / Q000175:diagnosis* / Q000453:epidemiology / Q000208:ethnology / Q000517:prevention & control; D018479:Early Intervention, Educational; D004519:Education, Special / Q000706:statistics & numerical data; D005260:Female; D006630:Hispanic or Latino / Q000706:statistics & numerical data; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008403:Mass Screening / Q000706:statistics & numerical data*; D011594:Psychometrics / Q000706:statistics & numerical data; D015203:Reproducibility of Results; D014481:United States; D044465:White People / Q000706:statistics & numerical data