title: Improved disability population estimates of functional limitation among American children aged 5-17.
abstract: OBJECTIVE
  This paper (a) creates and validates measures for population survey data to assess functional limitation in mobility, self-care, communication, and learning ability for school-age American children; (b) calculates rates of functional limitation using these measures, and provides population estimates of the number of children with limitations; and (c) examines these limitations as a function of socioeconomic factors.
  
  
  METHODS
  The study is based on data for children aged 5-17 collected in the 1994 National Health Interview Survey on Disability. Ordinal values are assigned to survey items in the four functional areas and analyzed to produce scales of high reliability. These measures are used to identify within a 95% confidence interval the number of children with these limitations. Ordered logistic regression models measure the effects of functional limitations on disability and societal limitation. Socioeconomic differences are measured with an ordered logistic regression model that predicts severity and comorbidity.
  
  
  RESULTS
  Limitations in learning ability (10.6%) and communication (5.5%) are the most common, with mobility (1.3%) and self-care (0.9%) occurring less often. Six percent of children have one serious functional limitation and 2.0% have two or more serious functional limitations. This corresponds to 4.0 million school-age American children with serious functional limitations. Functional limitation is strongly linked to socioeconomic disadvantage and to residence in single-mother households.
  
  
  CONCLUSIONS
  Future population research should use multiple-item scales for four distinct areas of functional limitation, and a summary that takes into account both severity and comorbidity. The improved estimates of the number of school-age children with functional limitation in this paper may help contribute to a more informed scientific and policy discussion of functional limitation and disability among American school-age children. Future research on the disability process among children must consider the role of socioeconomic disadvantage and family structure.
authors.affiliation: Population Studies and Training Center, Brown University, Providence, Rhode Island 02912, USA. Dennis_Hogan@brown.edu
authors.forename: D P
authors.initials: DP
authors.lastname: Hogan
authors.forename: M E
authors.initials: ME
authors.lastname: Msall
authors.forename: M L
authors.initials: ML
authors.lastname: Rogers
authors.forename: R C
authors.initials: RC
authors.lastname: Avery
mesh_terms: D000203:Activities of Daily Living; D000293:Adolescent; D017677:Age Distribution; D000465:Algorithms; D002648:Child; D002675:Child, Preschool; D004185:Disability Evaluation; D019988:Children with Disabilities / Q000145:classification / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D015999:Multivariate Analysis; D011159:Population Surveillance; D015995:Prevalence; D012042:Registries; D015203:Reproducibility of Results; D012307:Risk Factors; D012720:Severity of Illness Index; D017678:Sex Distribution; D012959:Socioeconomic Factors; D011795:Surveys and Questionnaires; D014481:United States / Q000453:epidemiology