title: Development of a parent-reported questionnaire evaluating upper limb activity limitation in children with cerebral palsy.
abstract: OBJECTIVE
  Upper limb activity measures for children with cerebral palsy have a number of limitations, for example, lack of validity and poor responsiveness. To overcome these limitations, we developed the Children's Arm Rehabilitation Measure (ChARM), a parent-reported questionnaire validated for children with cerebral palsy aged 5-16 years. This paper describes both the development of the ChARM items and response categories and its psychometric testing and further refinement using the Rasch measurement model.
  
  
  METHODS
  To generate valid items for the ChARM, we collected goals of therapy specifically developed by therapists, children with cerebral palsy, and their parents for improving activity limitation of the upper limb. The activities, which were the focus of these goals, formed the basis for the items. Therapists typically break an activity into natural stages for the purpose of improving activity performance, and these natural orders of achievement formed each item's response options. Items underwent face validity testing with health care professionals, parents of children with cerebral palsy, academics, and lay persons. A Rasch analysis was performed on ChARM questionnaires completed by the parents of 170 children with cerebral palsy from 12 hospital paediatric services. The ChARM was amended, and the procedure repeated on 148 ChARMs (from children's mean age: 10 years and 1 month; range: 4 years and 8 months to 16 years and 11 months; 85 males; Manual Ability Classification System Levels I = 9, II = 26, III = 48, IV = 45, and V = 18).
  
  
  RESULTS
  The final 19-item unidimensional questionnaire displayed fit to the Rasch model (chi-square p = .18), excellent reliability (person separation index = 0.95, α = 0.95), and no floor or ceiling effects. Items showed no response bias for gender, distribution of impairment, age, or learning disability.
  
  
  CONCLUSIONS
  The ChARM is a psychometrically sound measure of upper limb activity validated for children with cerebral palsy aged 5-16 years. The ChARM is freely available for use to clinicians and nonprofit organisations.
authors.affiliation: Academic Department of Rehabilitation Medicine, Faculty of Medicine and Health, University of Leeds, Leeds, United Kingdom of Great Britain and Northern Ireland.
authors.forename: N
authors.initials: N
authors.lastname: Preston
authors.affiliation: Academic Department of Rehabilitation Medicine, Faculty of Medicine and Health, University of Leeds, Leeds, United Kingdom of Great Britain and Northern Ireland.
authors.forename: M
authors.initials: M
authors.lastname: Horton
authors.affiliation: School of Mechanical Engineering, University of Leeds, Leeds, United Kingdom of Great Britain and Northern Ireland.
authors.forename: M
authors.initials: M
authors.lastname: Levesley
authors.affiliation: School of Psychology, Faculty of Medicine and Health, University of Leeds, Leeds, United Kingdom of Great Britain and Northern Ireland.
authors.forename: M
authors.initials: M
authors.lastname: Mon-Williams
authors.affiliation: National Demonstration Centre in Rehabilitation, Leeds Teaching Hospitals NHS Trust, Leeds, United Kingdom of Great Britain and Northern Ireland.|Academic Department of Rehabilitation Medicine, Leeds Institute of Rheumatic and Musculoskeletal Medicine, School of Medicine, Faculty of Medicine and Health, University of Leeds, Leeds, United Kingdom of Great Britain and Northern Ireland.
authors.forename: R J
authors.initials: RJ
authors.lastname: O'Connor
mesh_terms: D000293:Adolescent; D002547:Cerebral Palsy / Q000534:rehabilitation*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008297:Male; D010290:Parents; D011594:Psychometrics; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires; D034941:Upper Extremity / Q000503:physiopathology*
keywords: Rasch; cerebral palsy; measurement; paediatrics; upper limb function