VALIDATION OF A SCHOOL CLIMATE INSTRUMENT USING A RASCH RATING SCALE MODEL

A new ESSA indicator of school quality and student success provides flexibility to broaden a states’ definition of school and student success. Educational research has found school success is in part determined by a school’s climate and should be considered in improvement/reform strategies (Cohen et al., 2009; Thapa et al., 2013). Yet, school climate research is often difficult and time consuming, and employs a variety of conflicting definitions and dimensions, instruments, and empirical approaches to determining school climate. Given these significant limitations with current measures, the purpose of this study was to validate an instrument measuring school climate based on the four most commonly accepted dimensions of school climate, using items adapted from a well-regarded and established theoretical framework to provide an effective measure for educators and researchers. The sample selected for this study was a portion of teachers who indicated teaching 3rd or 8th grade as their primary teaching assignment (n=500) from the larger study sample (n=4974). A Rasch Rating Scale Model was used to evaluate unidimensionality, item fit and difficulty, reliability, and potential differential item functioning on a 23-item school climate survey. Results of the study showed the instrument was not unidimensional and was split into two subdimensions: student-centered and teacher/school support. All items were retained and displayed appropriate fit. Significant differential item functioning (DIF) was found between 3rd and 8th grade teachers on both subdimensions, further suggesting multidimensionality in the scale. Study findings suggest researchers should be mindful of any school climate instrument not validated at the item level for unidimensionality, and that an instrument may perform differently for teachers at different grade levels