Rater Reliability and Internal Scale and Person Response Validity of the School Assessment of Motor and Process Skills

Abstract

Abstract Objective. The purpose of this study was to examine the internal scale and person response validity as well as intrarater reliability of the School Assessment of Motor and Process Skills (School AMPS). Method. Fifty-four students were assessed with the School AMPS while they performed routine school work tasks in their classrooms. The students’ ages ranged from 3 to 7 years (M = 4.0 years, SD = .7). Twenty-two students were identified as “typically developing,” and 32 were identified as having a developmental or learning disability. Results. The School AMPS Motor and Process scale items and tasks (scale validity), the participants (person response validity), and the rater (intrarater reliability) all demonstrated acceptable goodness-of-fit to the many faceted Rasch model (MnSq < 1.4, z < 2). Conclusion. Results supported the validity and reliability of the School AMPS. With additional research and development, the School AMPS has the potential to become the first functional, unobtrusive, reliable, and valid assessment designed by occupational therapists for use by school-based occupational therapists.