title: Structural validity of the Movement ABC-2 test: factor structure comparisons across three age groups.
abstract: BACKGROUND
  The Movement ABC test is one of the most widely used assessments in the field of Developmental Coordination Disorder (DCD). Improvements to the 2nd edition of the test (M-ABC-2) include an extension of the age range and reduction in the number of age bands as well as revision of tasks. The total test score provides a measure of motor performance, which can be used to help make a diagnosis of DCD. M-ABC-2 also provides 3 sub-scales for Manual Dexterity, Aiming and Catching and Balance but the validity of these conceptually derived sub-scales has not previously been reported.
  
  
  OBJECTIVE
  To examine the factor structure of the M-ABC-2 test across the three age bands (AB): AB1 (3-6-year olds), AB2 (7-10-year olds) and AB3 (11-16-year olds).
  
  
  METHODS
  Data from the 2007 standardisation sample (N=1172) were used in this study. Confirmatory factor analyses (CFA) and structural equation modelling (LISREL 8.8) were employed to explore the relationship between the tasks within each of the 3 age bands. A model trimming approach was used to arrive at a well fitting model.
  
  
  RESULTS
  In AB1 a complex factor structure emerged providing evidence for an independent general factor, as well as specific factors representing the 3 test components. In AB2 a final model emerged with four correlated factors, an additional distinction being drawn between static and dynamic balance. In addition, a 2nd order general factor explained a considerable amount of variance in each primary factor. In AB3 CFA supported the 3-factor structure of the M-ABC-2, with only modest correlations between each factor.
  
  
  CONCLUSIONS
  The confirmatory factor analyses undertaken in this study further validate the structural validity of the M-ABC-2 as it has developed over time. Although its tasks are largely associated with the three sub-components within each age band, there was also clear evidence for a change in the factor structure towards differentiation in motor abilities with age.
authors.affiliation: Department of Psychology, University of Hertfordshire, UK. j.schulz@herts.ac.uk
authors.forename: Joerg
authors.initials: J
authors.lastname: Schulz
authors.forename: Sheila E
authors.initials: SE
authors.lastname: Henderson
authors.forename: David A
authors.initials: DA
authors.lastname: Sugden
authors.forename: Anna L
authors.initials: AL
authors.lastname: Barnett
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005163:Factor Analysis, Statistical; D005260:Female; D006801:Humans; D008297:Male; D009048:Motor Skills / Q000502:physiology*; D019957:Motor Skills Disorders / Q000175:diagnosis*; D009068:Movement / Q000502:physiology; D015203:Reproducibility of Results