The School Outcomes Measure (SOM) measures the outcomes of students who receive school-based occupational and physical therapies in the USA. This study examined the SOM’s discriminative ability and internal consistency. Descriptive data from a previous study of 73 students, classified by gross motor function classification (GMFCS) level of disability, was computed to determine the frequency of use of the SOM items and differences in subscale scores by students with various ages and levels of disability. There were no differences in mean subscale scores based on age; however students with less severe disabilities (GMFCS I–III) had higher mean scores in all subscales except expresses learning all students and behavior. Cronbach’s alpha coefficient was used to examine the internal consistency of items of the SOM. The correlations between many of the items within the subscales were high (.87–.99). Lower alpha coefficients were noted when the SOM was applied to students in GMFCS Levels II and III on two subscales when compared to GMFCS Levels I, IV, and V. On the basis of this evaluation, we revised the SOM to prepare it for a national field testing to measure its construct validity. 1. Introduction Both individual and program outcomes measurement are important for determining effectiveness of student interventions and to provide occupational therapists and physical therapists, who work in the school setting, with information to make decisions about treatment approaches and program planning.Individual tools measure outcomes of individual students over time [1]. Program outcome measures compare outcomes over time in groups of students at local, state, or national levels. Used in multivariable models, program outcome measures can also identify variables with which various outcomes are associated, such as service delivery models, types of intervention, child characteristics (e.g., age, sex, and diagnosis), and service intensity [2]. Although school-based occupational therapists and physical therapists in the USA are expected to measure the effectiveness of their interventions with the students they serve [3–5], no tool currently exists that measures either individual or program outcomes of students with disabilities who receive school-based occupational therapy or physical therapy services. Nor does a minimal data set exist for school-based therapists to identify variables of service delivery, type and intensity of intervention, and student and therapist characteristics that may be associated with student outcomes. The School Outcomes Measure (SOM) is a program
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