The study evaluated the ability of each item of the Test of Infant Motor Performance to separate children into developmental outcome groups.
Ninety-six infants with typical development (n = 67), cerebral palsy (n = 10) or developmental delay (n = 8) participated.
A retrospective study was conducted using an existing Test of Infant Motor Performance data set. Discriminant analyses of items' rates of change at eight and 13 weeks' corrected age (independent variables) and outcome groups (dependent variables) were run.
Data obtained at eight weeks' corrected age showed better discrimination and predictive validity than at 13 weeks' corrected age. Item rates and directions of change combined differently to maximize the separation among outcome groups depending on age.
Motor behaviors that could identify cerebral palsy might differ with age, depending on (1) the stage of brain and body development, and (2) whether the motor ability level itself or the speed with which children acquire different motor skills is being evaluated.
The authors suggest that different items' rate of change were helpful in discriminating among infants with different outcomes—thus rates of change in children's motor performance are as important as their ability levels.
Department of Occupational Therapy, Federal University of Minas Gerais, Minas Gerais, Brazil (V.M.B.); Pathways Center for Children With Disability, Glenview, Illinois (V.M.B.); and Department of Physical Therapy (S.K.C.) and Institute for Health Research and Policy (M.B.), University of Illinois at Chicago
Address correspondence to: Vanessa Maziero Barbosa, PhD, 1335 S. Prairie St., #2007, Chicago, IL 60605. E-mail: firstname.lastname@example.org
Grant Support: The first author's (V.M.B) work was supported by CAPES-Brazilian Ministry of Education, Brasilia, Brazil. The second author's (S.K.C) work was funded by the National Center for Medical Rehabilitation Research of the National Institute of Child Health and Human Development, United States Public Health Service (USPHS) (ROI HD 32567).
The study was completed while the first author (V.M.B) was a doctoral student in Disability Studies at the University of Illinois Chicago.