Use of the Rasch Model for Fit Statistics and Rating Scale Diagnosis for the Student Perception Appraisal

Background and Purpose: Nursing student retention is essential to meet workforce demands. Jeffreys' Nursing Student Retention Student Perception Appraisal-Revised (SPA-R1) has been used extensively to understand factors that impact retention. Psychometric testing of the SPA-R1 contributes to greater confidence in the instrument's reliability and validity. Methods: Item response theory and specifically, the single parameter polytomous Rasch model was used as a framework for fit statistic testing and rating scale diagnostics of the SPA-R1. This was a secondary analysis of a convenience sample of undergraduate prelicensure nursing students. The setting for the previous study was virtual, and the study period was 2022. Results: The model item characteristic curves for the 27 items of the SPA-R1 have similar shapes and are clustered in proximity. Overall, there are three clusters of items evident in the Rasch standardized residual contrast. The Rasch scale diagnostics indicated that the scale appropriately monotonically increases. However, there is a greater than 5 logit distance between does not apply and severely restricts, between severely restricts and moderately restricts, and between does not restrict or support and moderately supports. These large threshold distances indicate that additional steps in the scale may be warranted. The items cover the mid-range of the amount of retention perceptions; however, there are no items that represent the highest magnitude of the perceived amount of influence on retention. Conclusions: This study contributes further evidence to support the validity and reliability of the SPA-R1. We recommend adding steps to the scale, removing the does not apply response option, and considering scoring by three domains or clusters.