Cross-regional validation of the School Version of the Assessment of Motor and Process Skills.

OBJECTIVE The objective was to determine whether the School Version of the Assessment of Motor and Process Skills (School AMPS) is valid when used to evaluate students in different world regions. METHOD Participants were 984 students, ages 3-13 yr, from North America, Australia and New Zealand, United Kingdom, and the Nordic countries, matched for age and diagnoses. We used FACETS many-faceted Rasch analyses to generate item difficulty calibrations by region and evaluate for significant differential item functioning (DIF) and differential test functioning (DTF). RESULTS Four School AMPS items demonstrated DIF but resulted in no DTF. CONCLUSION This study provided support for occupational therapists using the School AMPS to evaluate students' quality of schoolwork task performances across regions because the School AMPS measures are free of bias associated with world region.